How to Choose Baby Monitor?

In order to better take care of the baby, moms and dads need baby monitors as their helper. But baby monitors have different models and styles. How to choose baby monitors? Here are several aspects when parents need to buy baby monitors need to consider. Baby monitors generally have three classifications: ordinary wireless type, straight recording type, and infinite distance type. Different types have different applications. So mothers should choose Video Baby Monitor according to their own family's needs.

1.Baby staying alone while mother doing housework; 2. Baby sleeping in the room while mother watching TV in the living room; 3. At night baby and mother sleeping separately. Common wireless baby monitor is suitable for those situations mentioned. The wireless baby monitor has one transmitter and one receiver end. Put the transmitter next to baby and mom carries the receiver with herself. For choosing this wireless type, here are some standards: a.is screen clear or not; b. when the environment around baby is weak lighting, is the screen bright enough or not; c. in totally black, is the camera can still display or not; d. is the wireless radiation excessive or not (most mothers may have no specific values compared with, but generally brand products and products for exporting are better); e. is the signal interference immunity good enough or not, otherwise other wireless signal could easily be effected (such as home wireless router).



4. Mother left house, when come back need to know what happened during this period. For that situation, straight recording baby monitor is suitable-record and display. For choosing recording monitor, the standards are: a. is the screen clear or not; b. has vocal recording function or not; c. monitor appearance is good or not; d. is the recording time long enough or not.

5. Mother is in company or business trip and wants to monitor at any time. This case parent can choose infinite distance type Digital Baby Monitors. Put a signal collection end at home. Via wireless or wired accessto broadband, mom can see through internet computers or mobile phones. Select this type here are indicators to consider: a. transmitting terminal size; b. can it support wireless access to broadband (wired connection after all is unconvinient and not good looking as wireless); c. is the setting simple or not (involves networking, to do settings the simpler the better for moms); d. is it stable enough or not (make sure it can work at any time indeed).

www.china-jlt.com is a high-tech enterprise specializing in the R&D, manufacture and sale of wireless baby monitors, wireless home security cameras and other wireless products. Exporting since 2003, they have served a long list of customers from Europe and North America and accumulated rich experience in marketing wireless items.

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Energy saving and environmental protection first I start from the low-carbon economy Ming LED lights

The emergence of the world's extreme weather and disaster come frequently, the reality of global warming by the "legend", low-carbon environmental protection has become a people must face the problem of low-carbon environmental protection has become the theme of the World Development. There is no doubt that as life's most widely used lighting tools should go the road of low-carbon environment, otherwise the consequences very serious ". Step It is understood that the awakening of the people have responded to low-carbon action, replacing the more environmentally friendly LED energy-saving lamps is action, Dongguan the Huachen Optoelectronics Technology Co., Ltd. is the domestic a research and development, production, sales and engineering services as one of the LED public lighting and commercial lighting manufacturers. Sky Lanterns the Huachen Optoelectronics Technology Co., Ltd. developed by a new type of colloidal materials with MCOB package technology, a breakthrough LED lamps heat and light efficiency bottleneck effectively reduce the number of chip size, heat dissipation materials and structural design cost, and thus the product costs by 40%. The Huachen the photoelectric optical components project gradually production, lay the foundation for the growth of the company's main business.
The lateral penetration industrial strategy of the Company "material - devices - components" raise investment projects with the laser optical components production in mid-2011, about to enter a new level Huachen photoelectric products Kongming high-power LED street light Kongming tunnel lamps, ceiling lamps Ming Kongming Downlight LED commercial lighting products. The great advantage of its products have also become a peer leader. LED light source life of up to 50000-100000 hours, more than 10 times longer life than traditional light source, greatly reducing replacement and maintenance costs of the light source, known as the light never goes out; LED is a green light spectrum there is no ultraviolet and infrared, low heat, no radiation; no strobe vision; no mercury elements, and can kill harmful substances in the air, to remove a variety of toxic chemicals to remove the life of a variety of odors, the rapid elimination smoke in the air; superconducting chip is environmentally friendly high-tech, high-performance products, available in red, yellow, blue, green, white and full-color RGB color single lamp, 3 light 5 lamp spot module brighter than traditional lights; more ability to adapt to the environment, indoors, outdoors in -40 ° C to 85 ° C, humidity ≤ 65% can be normal safe operation, 5-10 years; built-in security identification and automatic processing of intelligent systems do not eliminate the use safety hazards, so that consumers ease of use; fully embodies the concept of environmental protection, and set off a new round of green consumption; Huachen the Kongming LED lamp is patented product, enjoy the the the technological monopoly advantage, and the advantage of the development of technical standards, play-oriented, other The manufacturers are in line to it; product design fully reflects the trend of the spirit, stylish, elegant, sections have creativity.

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Development of LED application-driven start

LED is highly efficient, energy-saving, environmental protection, new generation of light source products. As great prospects for the development of new industries, in recent years, quickly became the focus of the economic competition of the International Science and Technology.Guangdong provincial government attaches great importance to the development of the LED industry, the and clear LED industry as a focus on fostering the development of three strategic emerging industries, and in the planning and layout, capital investment, technology research, promote the application of aspects of a series of ahead of the deployment, and to promote the LED industry scale rapidly growing. LED industry in Guangdong Province, in 2010 the output value of 85.3 billion yuan output value of 150 billion yuan in 2011, nearly three-year compound annual growth rate of up to 80% as early as 2008, the Guangdong positive response to the national call to start the "million miles" LED street lamp demonstration project building in Guangzhou, Dongguan, Foshan, Zhongshan, Zhaoqing, Shantou City construction total mileage of 1,500 kilometers, about the size of 100,000 LED street lamp demonstration and extension projects. In 2011, Guangdong Province and start the Canton (state) music (Chang), Bo (Lo) deep (Shenzhen) New highway LED lighting demonstration projects to applications for development, step by step, there are plans to build a LED industry cluster starting from application-driven, Guangdong Province have been put forward the implementation of a series of special policies to build semiconductor lighting industrial policy support system.
"Guangdong LED industry development plan proposed 30 million indoor LED lights will be during the" 12th Five-Year "promotion subsidies in accordance with the proportion of 30-50%, and in the community building, and guide people to buy LED lights, fully pull LED industry development funds to support Guangdong Province "deployment to accelerate the cultivation and development of strategic emerging industries views on the implementation of the State Council, pointed out that the" 12th Five-Year "period, the centralized financial Guangdong Province invested 22 billion yuan to support the development of strategic emerging industries , including arrangements for some of the funds to set up a special fund for development of strategic emerging industries, the focus used to support new high-end electronic information, new energy vehicles, three semiconductor lighting industry for emerging industries and fast technological progress, for the emergence of a new technology content high LED products, immediately establishing standards, and to seize the opportunities in the international market.
Meanwhile, the Science and Technology Department of Guangdong Province also give full play to the role of special financial fund leverage key support to the new technology roadmap to overcome solid micro laser peel equipment, metal base vertical structure of the high-power LED chip key core technology to break through the the foreign blockade or fill the gapstechnical high ground to seize the industrial development of the Guangdong Provincial Science and Technology Department Director Li Xinghua frankly, there is a lot of common problems restricting the development of LED industry in Guangdong. Aspects of technological innovation, technological innovation and breakthrough in upstream epitaxial silicon is increasing year by year, but the industry as a whole technical level remains to be improved, the core equipment and the key technologies needed to accelerate the breakthrough. Aspects of marketing, the LED demonstration projects still need to improve the business model, the traditional pattern of interests to be a breakthrough.
In terms of quality standards, pending further innovative ideas, a new way to explore the benchmark index, enhance product quality control. Next, Guangdong To fully understand the confidence and determination to promote LED lighting products, do a good job overall design of industrial development, focusing on support to overcome the the LED core of key technology to new technology roadmap, and vigorously promote the "contract energy management + supply chain + financial new business model in order to expand the LED market size, to promote Guangdong transformation by the large province of LED to the LED strong province.

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What is Wireless Mouse

The introduction of wireless mouse

Currently widely used wireless mouse uses a battery to supply power. Replace of the battery and brings inconvenience to the users. This paper presents a suitable for wireless mouse contactless power supply circuit, which comprises a contactless power supply of the primary circuit and the secondary circuit of 2 parts. Power supply device using USB power supply, voltage of 5 V, the self-excited oscillation circuit generates about 138 kHz high frequency oscillation voltage. The wireless mouse manufacturer will develop this technology all the time. The mouse pad built-in contactless coupling the primary coil carrying current output. Wireless mouse with built-in secondary current-carrying coil adopts contactless inductive coupling mode for obtaining electric energy, by the voltage integration chip to form a voltage regulating circuit, load voltage of 3.1V.

The use of the wireless mouse

The mouse is the most commonly used computer input device, along with PDA, notebook, wearable computer and portable devices such as pop, traditional mouse has been unable to meet the requirements for mobile office. The existing roller or photoelectric mouse needs a flat work surface, and its size is relatively large. The wireless mouse based on micro accelerometer is complete without this limitation, it can take one's ease in moving air to control computer; can be made very small, easy to carry, can be flexibly used in various occasions, such as: can be made for the disabled head wearing type mouse, for speakers to use mobile mouse.



The working principle of OEM mouse

Mouse according to their working principle can be divided into mechanical type and photoelectric type two, the most common is the mechanical mouse. Now the mechanical mouse is actually OEM mouse, the roller mechanical rotation is converted into an optical signal, and then converted into electrical signal. Roller type mouse is on the wheel drive X and Y axis on a decoding wheel to rotate, to sense the change of displacement of mouse; optical mouse is a self-contained light source of the photoelectric sensor, follow the movement of the mouse continuous recording of it through the surface of the "snapshot", these snapshots (frame) with certain frequency, size and resolution, and photoelectric mouse -- the core of DSP by comparing the differences between these snapshots to identify the moving direction and displacement, and the displacement of the information to be encoded real-time transmitted to the host computer.

www.mousekeyboard.net is a professional OEM plastic mould manufacturer and has engaged in wireless keyboard mouse combo product R&D, mould development, injection and assembly.

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LED market is flooded with cheap inferior products in the next three years or phase-out of more than half of the company

The LED listed companies or wearing ST cap, some enterprises even delisting. Flush statistics show that in the beginning of the year to November 10, the LED business listing seven, stock prices all fell sharply, down from 20% to 65% range, not only is the market environment fell from performance The seven four performance decline, the lowest decline by 18%, the highest decline of 94%. Flush Statistics show that 20 listed companies, 13 of the company's third quarter net profit fell the Jiawei shares Silan, BDO Runda, Nanda photoelectric decline of up to 92%, 88%, 57% and 52 %, while the seven listed companies only growth performance, the leading three safety photoelectric operating income, net profit were also increased by only 23% and 13%, respectively, increased by only 5% and 20% of the ground on photovoltaic these two indicators, The two companies in 2011, 2010, the performance increase is generally maintained at about 100% and 50%. A number of LED very meager profits of the listed companies in the third quarter, as Jiawei shares third quarter net profit of only 342 million, of Silan and Chau Ming Technology is also just a profit of 15 million yuan and 18 million yuan in 2011, following Jun the enterprises established company, Bo Lunte photoelectric, this year's Vision photoelectric company gone out of business recently to invest a billion LED display Haobo photoelectric struggling with financial difficulties and arrears huge amount of money and staff salaries and commission At this point, however, there are a lot of home appliance giant is entering the lighting market. In this regard, Yin Kang, co-founder of Shanghai Teyou Shi lighting are not optimistic. Vice chairman and secretary general of the China Association of Lighting Chen Yansheng said: "sell the bulbs and sell TV different appliance giants want to sell fixtures, the game is the use of appliances channels."

Emerging LED industry was mixed, there are many low-cost low-quality strategy, some LED products in the enterprise is reduced to a rubbish Chen Yansheng told reporters that more than 50% of the lamps were manufactured in China, Japan lighting market. Chinese lighting industry has a certain status in the world, but is not strong enough. This industry has a capacity of over 2000 billion market, and why so many businesses are struggling?

In 2011, Guangdong LED industry production value reached 151.5 billion yuan, double growth for two consecutive years. January to September 2012, the unfavorable situation in the international financial crisis, increased downward pressure on economic, Guangdong LED industry contrarian growth in output value of 125 billion yuan, a year-on-year growth of 17.2%; expected output value of over 200 billion this year yuan, output value and scale continue to be among the first in the country. The data from the Science and Technology Department of Guangdong, Guangdong Province, LED listed companies amounted to more than 20, Kingsun, Hongli Opto-electronic companies has landed in the capital market, with a total market capitalization of more than 20 billion yuan, but statistics according to the the extensive evidence Hang Seng consulting company PRD enterprises to get involved in upstream materials and chip listed companies only BDO Runda, country star power and Neo-Neon, country star power in the middle reaches of the packaging industry in the larger, the rest of the majority of listed companies in the business or in the downstream lighting applications , operating income reached 10 billion enterprise is very rare for the implementation of the second five energy saving plan, since 2009 state LED lighting industry subsidies unabated. In May 2012, the Guangdong Provincial People's Government, in the province's public lighting in the area in three years the popularity of LED lighting products, drive the LED industry to achieve the goal of the annual output value of 500 billion yuan more than in 2015. From the Guangdong Science and Technology Department data show that since 2010, the Guangdong fiscal invested 1.35 billion yuan of special funds, and guide enterprises and social investment of nearly 60 million of matching funds. The new round of boom to promote the use of LED lighting products is on the rise Li Xinghua, Science and Technology Department of Guangdong Province, said in a public speech in financial investment is strong support for a key innovation in the field of LED industry breakthrough. State subsidies for new energy to bring a new round of investment, the insiders this LED "investment" referred to as "herding" blind obedience to follow suit, the LED investment into return more unpredictable.

Second, large enterprises get state subsidies, crazy LED investment project to establish the industrial base, but its profits have been since they rely on government subsidies, its sustainability controversial. Sanan Optoelectronics listed companies third quarter profit of 667 million yuan, subsidies of up to 328 million yuan, accounting for nearly half. Coincidentally, the the BDO Runda this year's mid-term net profit of $ 1.2 billion in government subsidies of up to 1.5 billion, the country star power of this data is about 25% of the huge subsidies that business investment impulse than. Sanan Optoelectronics decided to raise funds not exceeding a total of 63 billion investment Anhui Sanan Optoelectronics Co., Ltd. Wuhu photoelectric industrialization (Phase II) project and Anhui Sanan Optoelectronics Co., Ltd. LED application products industrialization projects, the public offering of shares of matter has been reported to the China Securities Regulatory Commission, is still under consideration, however, excessive investment makes industry capacity oversupply, and focused on the middle and lower reaches of the lower technical barriers. LED industry enterprises, including listed companies, will be faced with the cruel process of survival of the fittest, the Guangdong Provincial Science and Technology Department Director Li Xinghua admits Guangdong LED industry still faces many challenges:

First, technological progress and the new generation of products speed quickly, a short time the country is difficult to establish a unified and standard LED products quality standard system, causing quite a mixed bag of market products, is not conducive to the control of product quality;

The second is the LED as a strategic emerging industries, and its development has its own characteristics and laws to promote the application of LED products a tremendous impact on the traditional lighting rely on existing business models are hard to break the traditional pattern of interests;

Third, the self-sufficiency rate of the core technology of LED upstream industry, high dependence on foreign industry is still in the low-end of the innovation chain and value chain. These issues are not resolved, will hinder the rapid and healthy development of the LED industry Recently, a news report said Yuba parents found the child's blind to bath baby always open to two months, the doctor diagnosed, the culprit is a Blu-ray in the Yuba this The news pushed the cusp of the LED light industry. Chinese the lighting designer Federation vice president Xu Qinghui said in an interview with this reporter yesterday, commonly used heating Yuba bulb is actually a high-powered incandescent.

Yuba child's blindness should be the larger causal relationship exists, of course, does not rule out this baby has potential congenital retinopathy Yuba important incentive for energy is its blindness. However, the incandescent light emission of energy in the blue region is very low, this energy should be sufficient to cause damage. Higher intensity of visible light and infrared penetrating eye, brought together in the same location of the retina, causing burns - just like our to converge sun with a magnifying glass can burning matches and subsequently, Xu Qinghui continue through the the microblogging network approach that, LED energy saving and environmental protection. But under the strict requirements of the benchmark system, each LED manufacturers in their efforts to improve the light efficiency (light source to electric convert light efficiency). There is a simple and low cost to improve light efficiency: thinning phosphor, so that the bottom of the Blu-ray extra some. Out "efficient" light unnatural, uncomfortable the visual feel pale, and glare. And not only is uncomfortable, too strong blue LED is also on the retina caused by photochemical hazards, and can even lead to retinitis, the harm is irreparable, severe blinding. In view of this, the international community and our Blu-ray hazards have strict limits, but who also can not guarantee the cheap LED products are flooding the market have to comply with the safety standards.

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LED the lamp thermal conductivity material across the thermal silica film

Silicone thermal conductive sheet of thermal silica film thermal conductivity graphite sheet Thermal Conductive Pad thermally conductive double-sided adhesive with high thermal conductivity material across the electronic thermal conductivity of heat difficult problem to solve. Manufacturing according to customer requirements. The power thermal silica film manufacturers manufacturers larger space electronic equipment thermal design have been proven design here do not do elaborate. The rapid development of microelectronics technology, the chip size is getting smaller and smaller, while the operation speed is getting faster and faster, this means a greater amount of heat, such as 3.6G Pentium 4 Extreme Edition Intel processor running generate heat up to 115W, , higher demands on the chip cooling. Designers must adopt advanced cooling technology and excellent heat dissipation material to effectively remove heat, to ensure that the chip can withstand the highest temperature within normal working. Electronic equipment and terminal appearance of more and more to thin small development, TV development from CRT to LCD flat-panel TVs, desktop computer to a laptop, digital set-top boxes, portable CD, thermal design with traditional forms, due to class The product is relatively thin and small. Statistics data indicate electronic components temperature rise of 2 degrees, reliability, decreased by 10; temperature rise of 50 degrees when the life of 25-degree temperature rise 1/6. Temperature is the most important factor affecting equipment reliability. This requires technically take measures to restrict the chassis and components, temperature rise, which is a thermal design.

Thermal design principles, reduce heat, that the selection of better control methods and techniques, such as phase shift control technology, synchronous rectification technology and other technologies, the other is the selection of low-power devices, reducing the number of heating devices, to increase crude printed lines width, improve power efficiency. Enhance heat dissipation by conduction, radiation, convection technology to heat transfer, but the appearance of flat products, first of all, from the space can not be used more heat aluminum and fan, and not allowed to strengthen-cooled whole thermal design, can not use the convection form. The same radiation heat way flat space is difficult to do. Everyone wants to think the use of the chassis for heat, the thermal conductivity of soft silicone do not consider the benefits plus fan power, fan and fan and will not cause more dust, no fan sky noise can really take advantage of the machine casing heat? The power thermal silica film application opportunities.

Power thermal silica film is a heat transfer interface materials, sheet material, size and shape of the heating power devices arbitrary cut power thermal silica film has a good ability to conduct heat and insulating properties, and its role is filled heating power devices and cooling The gap between the power supply thermal silica film is an alternative to the best product of Dow Corning thermal grease thermal paste plus mica sheet (insulation material) dual cooling system. The coefficient of thermal conductivity of the product on silica gel fins 6.0W/mK, while the air thermal conductivity is 0.03w/mk; resistance to voltage breakdown value of 4000 volts or more, the insulation requirements can be used in most electronic devices. Process thickness from 0.5mm to 5mm range, plus 0.5mm one that 0.5mm1mm1.5mm2mm until 5mm, special requirements may be increased to 10mm, different thickness is to allow designers to easily fever the size of the gap between the body and cooling facilities to choose different thickness product reach The best filling effect. Power thermal silica film heat is so simple: one can! Key Features: thermal conductivity, insulation, self-adhesive, shock, filled. Now, across the electronic variety series of thermally conductive silicone products to market, and is widely used in the power supply, high power LED, radiator, flat-panel TVs, laptops, home appliances, automotive and electronics industries.

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LED backlight features

And compared to conventional CCFL Backlight, led backlight, the most significant advantage is that you can provide unparalleled color reproduction. By choosing the appropriate wavelength LED and match color film, LED backlight color reproduction range can meet the NTSC standard of 105% even more. In contrast, the traditional CRT TVs only about 85%, CCFL-backlit LCD TVs is only 65-75%.

picture quality is the life of the display industry, have the advantage of more bright colors would be overwhelming. According to the traditional view, LCD monitors especially flat-panel TVs because of color and response rate than CRT and PDP have been criticized, but once LED backlight, CRT and PDP in color will overwhelm the main competitors. In addition, the LED backlight to a certain extent caused by slow response of the tail. LED to jump-start, response rate reached NS level, is baiwanbei for CCFL. With such rapid response backlight, LCD display can instantly backlight blinking technology to eliminate normal LCD display there was a trailing fast moving objects blur, image quality will be significantly improved. More important is that using LED backlighting in different moments of monochromatic light switches, field sequential color can be achieved, so that you can completely take away cost around 30% of LCD color filter.

on the life, LED can be more than 100,000 hours, twice times the best CCFL, even watching TV 8 hours a day, you can see more than 30 years. And CCFL contain deadly mercury vapor within different LED is semiconductor solid state light sources, was an ideal green light. Since the EU began in July 2006, a comprehensive limit of electronic products containing mercury and other harmful elements into the, therefore, in order to use LED backlight LCD products during this period began to replace the CCFL and created excellent opportunities to the world. Cold cathode fluorescent tube needs high voltage AC drives, power transformer rectifier unit complex, and LED the secondary optics you can do very simple, without a lot of space, very thin fuselage could have done, and also reduce the weight a lot. SONY TX Series notebook computers as an example, and compared to the VAIO t series LCD cold cathode fluorescent tube, thickness reduced from 9mm to 4.5mm, weight is reduced by 26%. Mitsubishi Motors posted on SID2005 six-color LED backlight LCD TV only 5 cm! In addition, the LED can be lower than-40 ° c environment, rapid start, and CCFL is not work correctly in this kind of environment, good adaptability to the environment making LED backlit LCD monitor by the areas of military, aviation and exploration for all ages.

of course, current LED backlight also presented some problems. At present, the LED backlight is about 3-5 times of the same CCFL Backlight. Such a difference, enough to discourage the vast majority of manufacturers and users. Followed by cooling problems, LED back light source emits a lot of heat when it work, especially for large size LCD TV is more serious. So they need some forced cooling measures, such as fans, etc. There is also the problem of luminous efficiency. Currently about 30-35lm/W of the most efficient commercial LED light, luminous flux is only about one-second for CCFL (CCFL light emitting efficiency is about 60-70 lm/W), LED by greater power to achieve and CCFL brightness.

However, these issues are expected to be addressed within a relatively short period of time.

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New anti-theft alarm based on TWH9250 radar detection module

Burglar alarm of TWH9250 radar detection module with the substance constantly enrich and rapid improvement of people's living standards, people's safety awareness are constantly strengthen, many families and units installed security doors and windows, security doors and windows to ensure the personal and property safety. play a positive role. Important places like the vault, warehouse, Key Laboratory of like, however, rely on a simple anti-theft doors and windows is not enough, you must also install a burglar alarm device. Common burglar alarm infrared burglar alarm, touch burglar alarm, induction burglar alarm and magnetron burglar alarm; common drawback of these anti-theft alarm monitoring range memory in dead ends, and committing the crime for the criminal elements to provide the opportunity. In order to solve the problem of dead space monitoring not to adopt TWH9250 radar detection module [1], the design of a new type of all-round the dead ends microwave burglar alarm. the burglar alarm the an alarm detection should consider the anti-theft alarm with sound and light alarm function is also required on-site camera control, so, in the circuit structure In addition to the loop antenna for emitting microwaves on the design should also include the radar detection module, alarm integrated circuits, integrated audio power amplifier circuit infrared camera control circuit and the DC power supply circuit 5 parts. the burglar alarm circuit design

probing the Introduction module TWH9250

TWH9250 is a novel of the radar detection module, the module has the following characteristics:
< br> (1) microwave tube scanning emission detection distance;

(2) all-round no dead angle detection;

(3) low power consumption, can be battery-powered;

(4) internal circuit open collector output terminal is connected with a flexible, can directly drive a small relay action;

(5) end of light control and sensitivity adjustment end, to meet the kinds of occasions to use requirements;

(6) simple external circuit connected to the ring antenna and terminal implementing agencies, power can work. the module shape

TWH9250 pinout and internal circuit functional block diagram is shown in Figure

2. arises out with the loop antenna transmitted microwave signal to form a three-dimensional microwave alert network, when someone moving around in the net, it will produce human movement reflected back the microwave signal, microwave generation circuit weak low-frequency signals of moving objects. The signal is amplified by the two to about 70dB, and then turn into a double to identify the window voltage comparator circuit and the pulse width of the comparator circuit. When recognized that the amplitude and width of the signal voltage reaches the set requirements, the latch circuit is triggered, the trigger signal via the optical control door is supplied to the counter control circuit to perform the output delay processing, the delay time is set to 10s, and finally by the end-stage power tube collector output. To improve the stability of the performance of the microwave circuit, the accuracy of the comparison circuit, the various parts of the circuit by 4V and 7V regulators system separate power supply. The circuit when the initial power, subject to the 40s pre-stable time to enter the probe alert after as long as it does not power down, the circuit at any time in the detection state. TWH9250 module normal operating voltage of 12 V.

2, the alarm IC burglar alarm issued a similar fire engines sound, A2 uses LC246 alarm integrated circuits [1], and his first election the sound end that 8 pin power supply (3V), readers If you change the level of the selected sound end, the alarm sound can be obtained.

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PPTC protection device technology in automotive electronics

The PPTC device technology has been widely used in portable electrical appliances, mobile phones, computers and telecommunications equipment overcurrent and overheating the circuit protection design. Automotive Electronics Technology Committee launched a new standard of passive components, and to promote the application of polymer positive temperature coefficient device (PPTC) circuit protection technology in the automotive industry. New car designed mainly for electronic circuits and motor accessories such as power windows, power seats, sunroof control and telematics devices, designed to reduce costs and improve the reliability and functionality. Motor drive and control devices are subjected to some of the harsh working environment, but also requires continuous and reliable operation. Site failure can not be avoided, to select the correct circuit protection strategy will help to ensure the reliability of the product, and the manufacturer and customer maintenance costs to a minimum. Raychem Circuit Protection PolySwitch ™ polymer positive temperature coefficient (PPTC) resettable circuit protection devices, the architecture is more solid and reliable products, some common fault in the motor drive and control systems provide protection.

PolySwitch polymeric positive temperature coefficient devices supplier type lead type, shaft type, chip type, disk type and surface mount type. Polymeric positive temperature coefficient devices compact shape helps save valuable board space with resettable functionality, allows arranged at the location of the users do not have access to this layout users to easily replace traditional fuses need The location for the replacement, with the obvious difference compared. Since the polymer positive temperature coefficient device is a solid state device, it is also able to withstand mechanical shock and vibration, and can provide a reliable circuit protection for a variety of different applications.

Power Protection

The PolySwitch device has been applied to the power supply DC output of the overload and short circuit protection. Developed LVR series of PolySwitch devices can be applied in the AC main circuit power input. This product will be the AC line transformer, and other line-side device is placed in the the PolySwitch device product series within the scope of protection. These products can be careless in the neutral line is in the OFF state or the AC line voltage for 24 VAC input, it is possible to provide protection for the power supply. The LVR device is suitable for the power system, 120VAC and 240VAC voltage, maximum input current up to 400 mA. Higher current power supply system can be the PolySwitch device placement in the secondary side of the output circuit for the protection of the power failure caused by the overcurrent state.

RXE input / output interface protection

Many drives and control devices are equipped with a communications and data interface for the transfer of information between the various system components. The wiring of these interfaces are sometimes side by side with the AC or DC power cable laying. The harness may be due to normal wear and tear, accidents, install wiring error, or misuse of central distribution box, and a short circuit. If the power cable and communication cable short-circuit phenomenon, PolySwitch devices can protect any system that is connected with this short-circuit line to avoid the damage of the communication interface. In some cases, this phenomenon is likely to affect many systems. The PolySwitch device from the premises of the protection interface, you can significantly reduce downtime and repair costs of equipment common fault.

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Inverter power switch power key design engineers must know

The switching power supply is the use of modern power electronics technology, control switch turn-on and turn-off time ratio, to maintain a stable output voltage of a power supply; Inverter principle is to use a thyristor circuit direct current into alternating current, this corresponds to the rectifier The reverse process, defined as the inverter. Power supply, commonly understood by saying: an electronic appliances for us to provide a suitable voltage, current, waveform, and frequency converting means! Example: DC power supply, can be understood as the frequency is zero, the waveform is the power of the line. AC power conversion) (positive or negative, between the two electrodes for voltage alternating frequency, the power of the waveform, can be understood! No matter what kind of power, we can Differential and Integral mathematical put it in either the value of solving a little time, and the only solution! For example: square wave, whether the magnitude of the sine wave, square wave can be decomposed into odd harmonics cattle subharmonic! 3rd harmonic of our general values ​​to meet the requirements! The largest part of the accounting for power is fundamental. 

Become the main power transformer is basically high-frequency core FET power devices! Everyone understands that the field pipe switch state, so it is as power tubes, power output is square wave pulse field tube with a large amount of power power harmonic fundamental! Field tube power switch power tube, but also understand: the field pipe production loss of 90% in the Annals shutdown time production, because the turn-on and turn-off time has a lot of instant resistance! So, to solve the problem of switching power supply, in fact, the main work is how to reduce the opening of the turn-off losses, harmonic, we can filter to solve! Another point we need to understand is: field pipe instantly changes the voltage is very sensitive, so give it power power voltage should be stable! The last thing to understand is: great gate resistance, little voltage can be allowed to open, and basically does not require current. Field tube is a voltage-controlled components. 

Through the above, we understand that: to use the Airport: 
1, the supply voltage to stabilize. 
2, control the opening of the turn-off losses. 
3, due to lower gate resistance, to prevent misleading links. 
4, have low-pass the discharge circuit speed charging circuit, because the the field pipe gate capacitance capacitor charging to be fast, the discharge should be fast! So use totem pole circuit. 

We want to design a good power process: 
First: Determine Your Power input voltage. Tube selector switch Power switch current transformer volume, input voltage determines the switch breakdown voltage transformer input laps. 
Second: No matter what kind of voltage, power, power tube with the scene must have low-pass discharge and speed charging circuit. 
Third: the transformers have a snubber circuit to absorb the harmonic. 
Fourth: the the field pipe gate internal resistance to use resistance grounding is pulled low. 
Fifth: To select the appropriate switching frequency, to guarantee static loss is minimized while too, the highest conversion efficiency of field pipe. 
Sixth: To test the filter for the input voltage exceeds 75V, the resonant circuit as negative help function circuit. 
Seventh: The power is too large, to test the design of the filter PFC circuit access. 
Eighth: drive signal should be stable! And have more than 5V

Principle and design of switching power supply

Flyback switching power supply, fixed switching transformer core area after switching transformer volt-second capacity by flux increment ⊿ B (⊿ B = Bm-Br) the size of the primary coil and the switching transformer turns number N1 to decide. The strength of the magnetic induction is determined by the magnetic field strength, i.e. the flux incremental ⊿ B is the magnetic field strength to determine. Figure 2-50, the dotted line B for the initial magnetization curve of the switching transformer core, the so-called initial magnetization curve is switching transformer core with magnetic magnetization curve in the first, once the switch transformer core band magnetic initial magnetization curve no longer exists. Therefore, in the switching transformer, switching the magnetization of the transformer core is generally not to carry out the work of the initial magnetization curve, but with the increase and decrease of the magnetic field strength, the strength of the magnetic induction will be along the magnetization curve AB and ba, or magnetization curve cd and dc change back and forth.

When the magnetic field strength increases, the magnetic field strength of the switching transformer core magnetizing; When the magnetic field strength is reduced, the magnetic field strength of the switching transformer core demagnetization. The strength of the magnetic induction is determined by the magnetic field strength when the magnetic field is increased from 0 to H1 of the corresponding magnetic induction intensity along the magnetization curve by Br1 ab increased Bm1; When the magnetic field strength is decreased by H1 to 0:00, which corresponds to the magnetic induction intensity by Bm1 along the magnetization curve ba down to Br1. Without considering the direction of the magnetic flux, the amount of change of the magnetic flux is ⊿ B1, i.e. the flux increments ⊿ B1 = Bm1-BR1. If the magnetic field strength is further increased, from 0 to H2 of the magnetization curve will be along curve cd and DC corresponding to the magnetic flux generated incremental ⊿ B2 = BM2-Br2. <br> Figure 2-50 can be seen, corresponding to a different magnetic field strength, i.e., different excitation current, the magnetic flux change amount is not the same, and the amount of change in magnetic flux with the magnetic field strength is not a linear relationship.

Mutual change function graph of magnetic flux density and magnetic field strength. Curve B is the curve of the corresponding change of the intensity and the magnetic field strength of the magnetic induction; curve μ is the magnetic permeability and the magnetic field strength corresponding to the curve of the variation; curve iμ change curve corresponding to the excitation current and the magnetic field strength. B = μH (2-147) iμ = Uτ / L (2-148) (2-147) and (2-148), wherein, B is the magnetic flux density, H is the magnetic field strength,  μ is the magnetic permeability, iμ excitation current, U is the voltage applied to the both ends of the primary coil of the switching transformer, L is the inductance of the primary coil of the switching transformer, the  τ is the pulse width. Permeability place is not the magnetic induction intensity or magnetic field intensity minimum or maximum place, but in place of the magnetic induction or magnetic field strength to an intermediate value. When the permeability reaches a maximum, the permeability increases with the magnetic induction or magnetic field strength, and decreased rapidly; when the permeability will be decreased to near 0, we believe that the switching transformer core begins to saturate, as shown in Bs and Hs. In this case, the switch transformer primary coil inductance will drop to 0, the excitation current becomes infinite.

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Principle characteristics of infrared detectors and installation notes

Infrared detector is the most critical part of burglar alarm system directly determines the sensitivity and stability of the system, is the entire system of quality guarantee. China Security manufacturers in these years, both technical mastery and improvement in production capacity were significantly improved, this due to Chinese manufacturers are constantly absorbing foreign product design and production technology, and a focus on reducing costs, making security products began to be contractors were recognized, coupled with the low price for the customer has an important attraction, making rapid domestic growth in the market. Although the quality of domestic and imported products are still gaps, but in the user's security products are not familiar with the case, security products in China is still very competitive.

Many foreign manufacturers are recognized before foreign investors to substantially rely on technology to deal with the cost advantage of Chinese products, but the gap has narrowed in recent years, advantage-decreasing, China technically has gradually caught up with the overseas manufacturers, parts manufacturers more creative ability to launch products with distinctive features, allowing security product quality significantly increased. This phenomenon comes mainly from many manufacturers for brand awareness and the importance of product quality, increased investment and research and development efforts.

Principle and characteristics of infrared detectors

Humans have a constant body temperature, usually at around 37 degrees, will issue a specific wavelength of about 10 μ m infrared, passive infrared detector is by detection of emission from the work IR about 10 μ m. Human emission of infrared of about 10 μ m by Fresnel light filter has been enhanced together in infrared sensor on the source. Infrared sensor sources usually in Pyroelectric elements, such components in receiving the infrared radiation temperature changes the body lose charge balance, release to the external charge, follow-up after testing, the circuit can generate alarm signals.

1. Passive infrared detectors are aimed at the detection of radiation, so the Pyroelectric element infrared radiation of wavelengths of about 10 μ m to be very sensitive.

2. Just infrared radiation human-sensitive, in its radiation the Fresnel face is usually covered with a special filter, lead to significant environmental disturbance control.

3. Its sensors contain two series or parallel each other Pyroelectric element. But two electrodes made of direction is the opposite, environmental background radiation on almost two Pyroelectric components have the same role to produce Pyroelectric effect of offset, so the detector signal output.

4. Once the people within the region intrusion detection, infrared radiation through the body part focusing mirror, and was Pyroelectric Yuan receiver, but two Pyroelectric Yuan receiver to heat different Pyroelectric different cannot be offset through signal processing and alarm.

Advantages and disadvantages of passive infrared probe

Advantages: itself, not any type of radiation, power consumption of the device is small, hidden well, low prices.

Disadvantages: easy to interference from various sources of heat, sunlight; passive infrared penetration is poor, easy to block infrared radiation of human body, can not easily be detectors; susceptible to radio frequency radiation interference, environmental temperature and body temperature approached, detection sensitivity and decreased significantly, sometimes resulting in short-term failure.

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Car Wireless charging scheme based on Electromagnetic induction

During the long distance journey or business trip, in case the mobile phone battery runs out, people's normal lives have a great impact on the work. Now there have been car parts car cell phone chargers, but due to the different brands of mobile phone charging interface there is a big difference, so if you want to complete charging must be carried in the car charger that matches with their mobile phones, is not very convenient. And because the car power supply is limited, and several phones while charging can not be achieved. The light of the foregoing, is presented in-car wireless charger envisaged, will introduce Electromagnetic induction technology to charge fields, through the electro-magnetic, magneto-electric conversion, enabling mobile contactless charging, the core technology of transformer-like non-core processing.

2 Wireless charging

2.1 General block diagram of the programme 

This article presents a vehicle for charging the mobile phone brand new programmes, modules and system hardware diagram shown in Figure 1 and Figure 2, respectively.

2.2 hardware 

automotive cigarette lighter 12V rrA power inverter reverse it into the mains, Induction coil built into the base output terminal of the inverter. Because square spirals without connection part of the adjacent side to 90. There current mutations. Built-in inductive loop circular Helix of RADIUS 5 ∞ l rings.

Mobile phones receive duanyou receiver modules and the original charging circuit. Will receive the Induction coil, Rectifier, filter circuit with PCB technology integrated in the module that is small enough, placed in a mobile phone battery, receiver module output is 5V DC 11 a. Mobile phone battery provides power, so as to complete the Wireless charging function.

3 Wireless charging principles and parameters

3.1 operating principle

Wireless charging due to the Chargers and receivers ask current there is no direct link, coil current, voltage is produced by magnetic coupling, which is essentially a pair of transformer-coupled coils, coil in the magnet-free material, its equivalent circuit diagram as shown in Figure 3:

3.2 inductive electromotive force

, Loop 1 and loop 2 are located at the base and handset receiver module, assuming coil 1 (number of turns ". ) Pass to I-I......sirl current, line without 2 (turns to the ramp of a bridge) magnetic induction can be approximated as: the flux of coil 2 is:

Outlet of induction electromotive force for round 2:

So, simply adjust the two turns of the coil than can also play a role in transformation of wireless transmission, required charging voltage.

3.3 Rectifier filter

Because the receiver module in the Induction coil is AC induction to, in order to meet the requirements of mobile phone charger, must also include rectifier and filter circuit in the receiver module.

4 conclusions

This article uses electromagnetic induction study on wireless technologies for mobile phone chargers. Allows the charger to charge the battery with no current direct links. And charging for several phones in the car while providing service, convenience and economy, if applied to humid environments, such as bathrooms, its security can be revealed.

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FCC and ETSI requirements for ASK modulation/short-range UHF transmitters

For remote control key (RKE), home automation, home security systems and other unlicensed transmitters for wireless control devices, United States FCC and ETSI in Europe have provided their transmit power level limit. These power requirements on those wishing to launch devices and unintentional or spurious emissions shall apply. In conjunction with these power limits and follow the test procedure, to determine the power developed by the radiation are in conformity with the specifications. Test equipment set up and sent radiation characteristics on the relationship between the test result (passed or failed) can have a big impact.

This application note describes the amplitude shift keying (ASK) modulation spectrum, signal transmitter and the transmitter VCO phase noise transient frequency pulling effect on test results.

ASK modulation spectrum

Can understand ASK modulation spectrum, that is, with a periodic square wave signal to modulating an RF carrier signal, and then the spectral lines are "modified" to illustrate the randomness of the data flow. First of all, cycle square wave signals as is the data rate of 2T-1/T 1010 ... Do not return to zero (NRZ) data series, as shown in Figure 1. The square wave power spectra as shown in Figure 2, including zero frequency indicates the carrier frequency, F0. At this point, the carrier spectral line and F0 be normalized (1/2T) composed of an odd number of times the line frequency. Each spectral line of power and carrier (zero frequency) power ratio of the spectral lines from the bottom gives:

Cycle for 2T of square wave

Cycle for 2T of square wave power spectra

When you ASK modulated signals are real data, the randomness of the data correction for half a week sine wave power spectrum spectrum. Normalized to the carrier frequency power spectral density of a mathematical expression is:

Each side-lobe spectral density peaks and spectral density ratio of carrier frequency by type 1 strike.

The MAX1472 ASK transmitter with 4kHz square (8kbps data rate) of modulation spectrum. We can see that the sidelobe peaks are located in the 4kHz (that is, half the data rate) of an odd number of multiplier points. Note that the ASK modulated signal carrier line (or lobe) power and no modulation (CW) relationship between the carrier power. This is important, because sometimes the FCC and ETSI specification applies to relative power, sometimes applies to absolute power. If the transmitter stable radiation (no modulation) P0 Watts power and duty cycle for 50% ASK modulation data stream, the modulation of radiation after halving the total power, is P0/2. Moreover, the modulation sideband can form, so the main lobe of the frequency spectrum (carrier) only contain half of ASK modulated signal power. Thus, modulation sidelobe power and transmitter CW power compared to that in power ratio in Equation 1 minus 6dB (CW power and after ASK modulated carrier spectral lobe power ratio).

For example, a 315MHz of radiation not modulated carrier power 10mW transmitter after ASK modulated radiation only 5mW of power. 5mW, contained in 2.5mW only exist in waves in the flap, next to the 2.5mW scattered throughout the remaining flap. Therefore, when the data rate is 8kbps (see 1), next to the 101th flap (distance carrier frequency 404kHz) power: visible sidelobe power is not only better than wave ASK modulated signals contained in flap small 44dB, but smaller than the unmodulated CW carrier power 50dB.

Analysis of DC electric arc furnace electrode control system and its improvement

In DC electric arc furnace steel-making in the refining process, melting, melting, its initial stage of oxidation and reduction on power supply (voltage, current) have different requirements, energy efficiency, improving efficiency, achieve the best technical and economic indicators.

And communication control method of electric arc furnace steel-making does not, arc voltage of DC electric arc furnace (ARC voltage) and the arc stream (the arc current) size is two entirely independent conditioning system control, arc voltage and arc current can be adjusted independently of automatic linearly, to meet the requirements of smelting technology for power supply. ARC stream regulating system of thyristor rectifiers as regulation, automatic closed-loop stability of arc current flow regulator control thyristor rectifier output DC current, under static conditions, auto-steady flow system can maintain a constant arc flow unchanged. In the context of effective control, arc arcs caused by pressure changes do not flow with the change, which create the conditions for independent and adjust the arc length arc voltage. DC arc furnaces in steelmaking process, electrode lifting control system for electrode positioning mechanism for controlling object, whose primary role is to adjust the length of the arc column (ARC length). In accordance with the relevant documentation analysis, Va the arc voltage and arc length approximation between La and there is the following relationship:

Ka=0.6~1.1V/mm call in an arc voltage gradients, pressure gradient varies, depending on the size of the arc furnace atmosphere. Relative to the arc current and arc voltage rate of change, believing that Ka values change very slowly, can be approximated as a constant. Thus, arc voltage and arc grew up to be an approximate linear relationship. Adjust the arc length is equivalent to adjust the length of the arc voltage of high and low. When the arc when the stream is constant, adjust the arc length is equivalent to adjust the arc power level. ARC power Pa=IaVa. So, have a direct impact on the performance of the electrode lifting control system of electric power input and the furnace running.

2 the main problem and cause analysis

Gansu Tibetan metallurgical group special steel two nominal capacity of 5 tons of DC electric arc furnace steel-making in 1997 and began to put into trial operation, commissioning and discovered electrode lifting control system is not working properly, exists mainly in the form of:

(1) is not stable, electrode flees the frequent and of long duration, the arc furnace without continuous and stable access to effective power input;

(2) arc down, fifth tranche with the highest AC voltage, arc voltage (DC) values will only be around up to 250V, severely limiting the arc power increase, network side of transformer power factor is relatively low;

(3) the arc voltage adjustment range is small, real arc voltage values not follow change linearly with the given arc voltage values. Control of smelting technology of performance does not meet the requirements, do not accurately on stabilization of arc voltage at a given value of;

(4) circuit high failure rate, frequent power outages, maintenance, adjustment, or replace components, seriously impacting production. <br> according to the problems that occur in the course of trial run, after careful on-site observation and careful analysis of control circuit system, that occurs above the main cause of the problem has the following aspects:

Application of the sensor technology in the diesel engine

Sensor carbon dioxide emissions from fuel efficiency to reduce carbon dioxide emissions is the hottest topic in today's automotive sector. The European Commission recently announced a safer, more environmentally friendly cars roadmap to 2012. Significant change in the automotive consumer buying patterns also confirmed that consumers want to be able to meet their own personal and professional needs of the highest fuel efficiency car. Progress through the mixed-fuel technology, automotive manufacturers are introduced to reduce the carbon dioxide emissions of new cars. There are also some technical committed to this goal, such as Blue Motion, Econetic and Efficient Dynamics.

Diesel engine pollution than gasoline-powered car, which is a fact. In particular, the diesel particulate body injury, will cause lung irritation, cancer and heart disease. Older diesel engines will emit a larger visible particles, like black smoke, new engine particulate emissions are generally small, and can not be seen with the naked eye.

These emissions cleaner, car manufacturers to build a diesel particulate filter (diesel particulate filters DPF). Since 1980, these filters have been used for off-road vehicles, since 1996 for some ordinary car. DPF can now capture diesel soot particles down to 2.5 microns, therefore particulate emissions reduced from 60% to 7%. DPF using a porous ceramic material, and will eventually be saturated, and need to be cleaned and regenerated. For such maintenance requires heating the DPF to the exhaust gas temperature above +600 ℃. In order to achieve this a higher than normal temperature, the ECU (electronic control unit) will temporarily delaying the fuel injection, and restricting suction. In this case, the sensor become a key control element: by using a pressure sensor to measure the voltage drop on the filter, it can determine the most efficient point in time starts the regeneration process.

Interface Implementation

To the diesel filter module, for example, a traditional varistor element differential pressure sensor installed in the DPF. The pressure range of the sensor to check for a smaller, generally 0 to 15psi. A sensor interface IC (such as the Melexis MLC90320 CMOS analog sensor interface) connected to the sensor output terminal, and constitute a resistive Wheatstone bridge circuit. This interface can be a small change in voltage of the resistor (typically a few millivolts) is converted to the relatively large changes in the output voltage of. With this structure, the circuit to be able to compare the filter before and after the pressure signal. The interface chip for the sensor's signal for amplification and correction, it is converted into the value of the ECU to be able to identify. When the saturation of the DPF, the interface will be detected before the filter, there is a greater pressure differential between the signal after the. Interface IC for amplification and compensate for this difference, passed to the ECU. This process allows the sensor interface to control the communication between the detection element and the ECU, to ensure the filter for normal work.

Sensor interface

In the above example, the detection element of the varistor is connected to the input terminal of the sensor interface, and its signal for the compensation of the gain and offset, to determine the output signal of a well calibrated. In addition, using three different coarse stage and 10-bit digital-to-analog converter (DAC), the output of this particular interface architecture uses a 10 DAC, the output variation range for accurate calibration.

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Laser sensor-based smart car ramp detection

Laser-based sensor smart car, using a single level of irradiation of the laser sensor to detect ramp, make a corresponding control program for the ramp. Car models is automatically tracking, track information to rely on a relatively high degree of sensor accuracy and anti-jamming capability requirements are relatively high. Laser sensors by modulating the transmitter to avoid the natural light of its impact, and improve the anti-jamming capability. Compared to the laser sensor to the infrared sensor to a much higher priority in the operating range, therefore Prospects larger distance, greatly enhance the control effect, and the receiving circuit of the laser sensor can be obtained directly after the binarization results, eliminating the intermediate modulus conversion and binarization process, the collected signal return directly to the microcontroller is 0 and 1, to reduce the workload of the microcontroller, and improve the overall speed of operation of the microcontroller. Laser sensor can not overcome the problem, precisely because the role of the laser distance, it appeared difficult to detect ramp information.

A description of the problem

Laser sensor smart car uphill, the reflection of light due to light the role of changes in the distance and slope will produce interference signal laser sensor can not properly identify the position of the black line, and eventually Cars can not ramp. To solve this problem, there are a variety of solutions, these programs can be divided into two categories, one is blind law, and the other non-blind over law. The unblinded law process is as follows: First, the data collected by infrared sensors, and analog-to-digital conversion of data mined, mined in the vicinity of the black line data than the interference signal, and then through a simple filter can It is easy to judge the position of the black line. But this method requires modulus conversion, and requires the participation of the infrared sensor, also need to set the threshold is binarized to determine the location of the black lines, the hardware implementation and algorithm process is more complicated, and occupy more MCU resources. The process of blind through method are as follows: the first detected by some sort of ramp sensor ramp, once detected Claim shielding laser sensors, the use of the sensor to the data of the previous time to be estimated, when the the ramps sensor detects the model car has passed ramp, immediately open the laser sensor, car models into the normal driving state. The blind Compared with non-blind method, the main problem is too much blindness, but most of all because of the ramp on the track on the straights, so the impact is not great, but also can be coupled with a row of infrared sensors or role from the more recent laser sensor to overcome this defect. In this paper, an example to the blind over the law.

2 single laser tube ramp detection program

2.1 Hardware Design

Laser sensor works in Figure 1 shows, when the laser launch tube to the white part of the track, a lot of light through the diffuse reflection is reflected back the receiver tube light received, the data transferred to the microcontroller to 0, when the laser irradiated to the black portion of the track, a large number of the light is absorbed and does not receive the light receiving pipe. The data transferred to the microcontroller.

Determine whether remote control receiver normal method of resolving programme

1) identification of remote control receiver

If the remote too close or remote control anti-theft system did not work, should consider whether the remote control receiver circuit is faulty. Determines whether the remote control receiver normal, common methods are as follows.

① Spectrum Analyzer receiving antenna close to the receiver, to the anti-theft system (or remote control receiver) power, observed in the 200~400MHz within the band wave (adjustable volume) or gas (inductance) spectra of waveform. Such as a Spectrum Analyzer on the screen without any response, description receiver circuit faulty.

② use remote control transmitting signals, observed by oscilloscope receiver output (OUT), decode the input pulse signal output circuit. Due to different data signals that are sent, their waveforms for pulse width different combinations of strings, such as wave waveform was not unusual or logging, description remote control receiver section is defective.

③ Oscilloscope observation remote control receiver signal output, with metal objects touch remote control receiver antenna transmission of persons end clutter of oscilloscope should have a stronger reaction, otherwise description receiver part is faulty.

④ remote control transmitting signals, block measuring signal output voltage of DC voltage with multimeter, when you press the remote control button, the output voltage changes, in the absence of any response, description receiver circuit faulty.

(2) the remote control receiver determination of fault location

Once remote control receiver circuits are not working properly, you can distinguish fault from which part of the circuit as follows, that is, from upgrading a circuit is high level grade, super zoom, shaping circuits.

① When you check the amplifier, plastic circuit, signal/output points are lost people find the critical points of failure. Specific method is with remote control launches signal, with oscilloscope observation zoom, and plastic circuit has no signal entered (as LM385F of ⑤ feet), as has signal waveform, description high level circuit, and Super again rose circuit basic normal, fault in zoom, and plastic circuit; as measuring does not to signal, is fault in Super again rose circuit zhiqian: on zoom, and plastic circuit of check, can measurement LM358 of introduction feet voltage, and and normal controlled, if does not normal, more for IC itself damaged.

② for Hyper-up overhaul of the circuit, you can first check the DC voltage of the transistor, if not normal, check the DC bias circuit or transistor itself. DC bias voltage is normal, check AC feedback circuit, chip capacitors it is best to use the Replace method to examine.

③ for maintenance of high frequency amplifier circuit, check first check the DC operating point of high-level pipe after coupling components are generally not difficult to isolate the failing component.

Is the received frequency offset from the highest failure rate, mostly because of water or stop oscillation circuit board damp Super up circuits. Car alarm system with receiver, both the inductance and the adjusting volume, whether discrete direct plug-in is a surface mount devices or mixed mode, almost entirely between them used interchangeably, if we can find the GND (ground), +V (Power), OUT (output signal) corresponds to the end of the relationship, and resize the receiving frequency of the receiver.

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NI industrial controllers introduced with the Intel Core Duo processor

The latest NI 31xx series of industrial controllers recently released, the series controller can be connected with the NI test and measurement platform, fanless design for long-term release applications. NI 3110 industrial controller is equipped with Intel SL9JT L2400, clocked at 1.66GHz dual-core processor and the NI 3100 industrial controller with Intel 1.06GHz Celeron M423 processor, two controllers are equipped with the Windows XP operating system. These new controllers for harsh environment, with or without fan cooling, and can be connected via USB, MXI Express, Ethernet and PCI or PCI Express to external equipment engineering applications, is an ideal choice! NI 3110 industrial controller, engineers will be able to build a flexible control system, so as to cope with dual-core processing and analysis functions multi-threaded applications. Engineers can use the NI 3110 industrial controller as an interface, and NI CompactDAQ, NI PXI and NI plug-and-play PCI and PCI Express hardware to control remote I / O The connection provides a high-performance, flexible test platform suitable for long-term use of durable system performance for the reliable release. In addition, engineers can use NI LabVIEW software to build human-machine interface (HMI), data acquisition and supervisory control system (SCADA) applications, and publish these applications in the industrial controller.

The controller can help engineers will add a series of connections, including the PCI Express, USB, Ethernet and PXI to specific applications. PXI system through the wired PCI Express can connect to these industrial remote controller can support integrated MXI Express chassis or any PXI chassis wired PCI Express interface supports test applications. At the same time, it is equipped with four USB ports and an industrial fanless controller, Windows XP, NI CompactDAQ or NI USB data acquisition devices with applications. In addition, by installing the board support PCI or PCI Express single-slot controller for NI R Series, M Series, industrial communication or fieldbus devices, engineers can obtain specific industrial test performance. For more connectivity, two Gigabit Ethernet interface for NI programmable automation controllers (PACs) to expand into the performance.

The use of these new industrial controllers, engineers can use two Ethernet interfaces and integrated video, adding HMI and touch screen flat screen LabVIEW Real-Time Module NI PACs. In addition, engineers can use LabVIEW Datalogging and Supervisory Control (DSC) module to create HMI and SCADA applications, and these applications published to the industrial controller. In addition, by using the LabVIEW DSC Module, engineers can interactively develop distributed monitoring system. Which greatly expand the performance of LabVIEW, so that it can monitor the real-time and historical test data, configure alarms and events, create safety issues in the application or easily carried the OPC device's networking and LabVIEW Real-Time targets record data to a historical database .

Chase new electronic press environment too fast

March 16, a new generation iPad in the first 10 countries and regions, including Hong Kong, China, officially opened for sale. IPad2 listed separated by less than a year, there are a lot of electronic products and even within a year can be a variety of products, which contributed to the New People like chase followed frequently let their various "toys" replacement, however, recycling and so the chain is not yet mature, can imagine the pressure on the environment.

The ultrafast electronic products is replacement chased more than just one or two, although there are some people refrained himself chasing new ideas, but more in the face of new technology "grass is always greener" mentality urging continue to buy. Internationally renowned investment bank analysts believe that the brand new Apple iPad global annual sales will reach 65.6 million units. Can imagine, and then cause the next-generation iPad officially listed the number of the previous generation product "backlog", "replace", "idle"?

If you buy a new product just old eliminated to others Fortunately But, according to some Chinese people play bad, tired of a habit to throw the garbage of electronic products in China are surprising speed growth.

Due to the the electronic waste degradation long time, water, soil, air, and will cause serious pollution, the pollution will be a button battery leakage six hundred thousand liters of water to manufacture a computer requires more than 350 kinds of harmful chemicals on human health and the environment raw materials. So once thrown away as waste, will become the the environment "killer". To speed the replacement of electronic products, this process is constantly shorter. The electronic products eliminated time in the past but also in terms of years, but in the present circumstances, I am afraid to become a "month".

Despite the latest news that Apple has further extended its official recycling program, iPad2 included in the recovery list and provide users with the gift card recycling incentives, but it is undeniable that far less than the strength of the company's recycling program also to cover the sales of the global market. If only recycling of e-waste, small traders door or the individual the Hand Workshop dismantling, burning, acid soaking is recycled in a manner considerations can imagine the harm to the environment.

Attention to environmental news readers may remember, last year, Apple and other electronics manufacturers frequently accused of the production process to produce large amounts of pollution. There have been a British environmental consulting firm test, each production will produce an iPad generates 286 pounds is equivalent to 130 kilograms of carbon dioxide emissions. There are currently a wide range of applications in electronic products of high-density printed circuit boards, high-energy-consuming products belong to the high water consumption, and need a lot of waste water and exhaust gas emissions in the production. If coupled with the pollution of these production processes, the production and use of the hot electronic products will be the future environmental nightmare.s

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