CN203340336U - A LED driving power supply and dimming system - Google Patents

Abstract

The utility model discloses an LED driving power and a light modulation system, comprising an alternative-input-rectification-filter unit, a flyback conversion unit, an output filter unit, a constant current output unit, a voltage sampling feedback unit, an opto-couplers isolation unit, an STC89C51 singlechip control module, a liquid crystal display module, a DS18B20 temperature detection module, a buzzer alarm module, an infrared transmission module, an infrared receiving module, and an auxiliary power module of the singlchip. The advantages of the LED driving power and the light modulation system have advantages of high efficiency, low cost, easy control, a simple peripheral circuit and strong practicality.

Description

A LED driving power supply and dimming system

technical field

The utility model relates to an LED driving power supply and a dimming system, which belongs to the field of electronic technology, especially the switching power supply.

Background technique

LED is a new generation of cold light source developed in the 1990s. It has incomparable advantages over traditional light sources: such as high conversion efficiency, low calorific value (no radiation), low power consumption, long life of 100,000 hours, and fast response. Fast (can be operated at high frequency), environmentally friendly (shock-resistant, impact-resistant and not easy to break, waste can be recycled, and pollution-free), small in size (multiple pieces, various combinations), easy to develop into thin and short products, LED light sources are called successors The fourth generation of light sources after incandescent, fluorescent and high-intensity gas lamps. Moreover, with the improvement of people's living standards and the development of electronic technology, people's requirements for the intelligence of lighting systems are getting higher and higher.

Since LED is a sensitive semiconductor device with negative temperature characteristics, its driving design becomes very complicated, and it cannot be directly powered by AC mains like traditional lighting equipment. The performance of the driver is directly related to the luminous flux of the LED, and also affects the photoelectric conversion efficiency of the whole set of lamps. If the driver is unqualified, the advantages of the LED cannot be fully reflected. It can be said that the driving power is as important as the heart in the whole lamp. In addition, it also affects the life of LED lighting equipment, and its high cost also restricts the large-scale application of LED in the field of general lighting, so the integration of its structure and electronic control is one of the problems to be solved urgently.

At present, the LED dimming methods on the market are mainly divided into three methods: linear dimming, thyristor dimming, and PWM dimming. Linear dimming is based on the principle of simple voltage division, which is simple to apply and low in efficiency; the working principle of thyristor dimming is to apply the principle of tangential to reduce the effective value of the output voltage, so as to reduce the power of ordinary loads, which is not suitable for direct use. for LED products. PWM dimming technology is currently considered to be the most promising LED dimming technology. When performing pulse width PWM dimming, it is necessary to provide an additional pulse width adjustment signal source to adjust the LED through the LED by changing the duty cycle of the input pulse signal. For the purpose of current size, the advantages of this dimming technology are simple application, high efficiency, good precision, and good dimming effect.

The single-chip microcomputer control technology is applied to the switching power supply, so that the switching power supply has stronger controllability, such as remote control dimming, which not only solves the trouble of groping for the wall switch in the dark, but also solves the problem caused by the fixed switch position when the room is rearranged. troubles come. Because infrared remote control has the characteristics of small size, low power consumption, strong function and low cost, it is already the most widely used means of communication and remote control.

Utility model content

The utility model mainly aims at the disadvantages of poor man-machine interaction, low degree of digital intelligence and single dimming mode of ordinary LED drive power supply, and designs an energy-saving, environmentally friendly and convenient LED drive power supply and dimming system; the utility model is designed The LED drive power supply and dimming system can be operated by man-machine interaction, and different brightness can be set according to different environments or requirements; the LED drive power supply and dimming system designed by the utility model can use an infrared remote control to control a single-chip microcomputer to generate two Group PWM to dim the two LED lamps; the LED drive power supply and dimming system designed by the utility model, the feedback circuit adopts a three-terminal off-line PWM switch, and the PWM controller and MOSFET power switch in the high-frequency switching power supply The tubes are integrated on the same chip, which eliminates the phenomenon of high-frequency radiation, improves the electromagnetic compatibility performance of the power supply, and reduces the requirements of the device on the layout of the circuit board and the transient of the input bus; the LED drive power supply and dimming The system adopts TL431CLP chip to provide precise reference voltage, which has the characteristics of small voltage reference error, low dynamic output impedance, low output noise voltage, etc.; the LED drive power designed by this utility model adopts MAX16822 step-down constant-current high-brightness LED driver, The output current is set by a high-side current detection resistor, and the dedicated PWM brightness adjustment input can realize pulse-type LED brightness adjustment with a wide brightness range; the LED drive power supply and dimming system designed by the utility model, in addition to one main output to the LED lamp In addition to the power supply, there are two auxiliary output circuits, one auxiliary output circuit supplies power to the optocoupler, and one auxiliary output circuit supplies power to the single-chip microcomputer; the LED dimming system designed by the utility model also has a liquid crystal display module, which can control the LED light current The brightness and temperature are displayed; the LED dimming system designed by the utility model also has a temperature sampling module, and an alarm is sent through a buzzer when the alarm value is exceeded.

According to the technical solution provided by the utility model, the design of the drive circuit, the topology of the main circuit is a flyback switching power supply topology, and the circuit includes: AC input rectification filter unit, flyback conversion unit, output filter unit, constant current Output unit, voltage sampling feedback unit, linear optocoupler isolation unit, STC89C51 single-chip microcomputer control module, DS18B20 temperature measurement module, buzzer alarm module, liquid crystal display module, infrared output module, infrared receiving module, auxiliary power supply module of single-chip microcomputer; The AC input rectification filter unit and the flyback conversion unit are sequentially connected to the constant current output terminal. One of the constant current output terminals supplies power to the LED, one to the optocoupler, and the other to the single-chip control module; at the main output terminal of the LED, it passes through a voltage divider network After sampling the voltage signal, input it to the reference terminal (Vref) of TL431CLP to control the shunt of the device from the cathode to the anode. This current directly drives the light-emitting part of the optocoupler U3, so when the output voltage tends to increase, Vref As it increases, the current flowing through TL431CLP increases, so the photocoupler luminescence is strengthened, and the feedback voltage obtained by the photosensitive end is also larger. After U2 receives this increased feedback voltage, it will change the switching time of the MOSFET, and the output voltage will change accordingly. And fall back; there is also a temperature acquisition module on the single-chip microcomputer, and the temperature acquisition module will display the collected temperature information on the LCD screen through the single-chip microcomputer; the infrared transmitter module of the handheld remote control can control the PWM output of different duty ratios according to different requirements of users. Control the brightness of the two LED lights separately to realize human-computer interaction.

The single-chip microcomputer module adopts STC89C51 single-chip microcomputer, which has the advantages of low cost, rich development resources, and convenient bit addressing. The use of a single-chip microcomputer for software decoding and PWM output greatly improves the flexibility of the circuit and reduces the cost. Only one or two buttons can be used to realize the switch and brightness adjustment of an LED, which is very practical.

The temperature measurement module adopts DS18B20 temperature sensor. When DS18B20 adopts a single-bus interface mode to connect with the microprocessor, only one line is needed to realize the two-way communication between the microprocessor and DS18B20. It has low cost and strong anti-interference ability, and is suitable for On-site temperature measurement in harsh environments, easy to use, etc. When the collected LED temperature exceeds the preset value, the buzzer connected to the single chip microcomputer will send out an alarm, timely reminding the maintenance and inspection of the power supply part, prolonging the working life of the LED lamp and its driving power and reducing the damage caused by the LED lamp Inconvenience to people's work and life.

The human-computer interaction module adopts a hand-held remote control type infrared emission module and an LCD liquid crystal screen to realize the interaction between human and single-chip microcomputer.

The infrared transmitting module adopts uPD6121G chip transmitting code format which is widely used and easy to decode to form a transmitting circuit. When the transmitter button is pressed, a remote control code is sent out. The key pressed is different, and the remote control code is also different. The single-chip microcomputer can generate PWM with different duty ratios according to the received different codes to remotely control the LED.

The infrared receiving module adopts an integrated infrared receiver, which integrates infrared receiving and amplifying, and can complete the work of receiving and outputting signals compatible with TTL level signals from infrared receiving without any external components, and the volume It is the same size as an ordinary plastic-encapsulated triode, and is suitable for various infrared remote control and infrared data transmission.

The LED drive power supply and dimming system has three outputs, one for powering two parallel LED modules, one for optocoupler and one for single-chip microcomputer module.

The LED driving power supply and the main circuit of the dimming system adopt TOPSwitch series single-chip switches, which greatly simplifies the design of the circuit and shortens the design cycle.

The LED drive power supply and dimming system adopts MAX16822 step-down constant current LED driver. The dedicated pulse width modulation (PWM) input can realize wide-range pulsed LED brightness adjustment, and the high-side current detection and internal current setting circuits reduce the Low external component count, and can provide ±3% accuracy of the average output current, the hysteretic control algorithm ensures excellent input power rejection and fast response performance during load transients and PWM dimming.

The LED driving power supply and dimming system can supply power to two parallel connected LED lighting modules, which are respectively controlled by PWM through a single-chip microcomputer.

The beneficial effects of the utility model are:

(1) The LED driving power supply and dimming system are low in cost, convenient in control, simple in peripheral circuits, simple and reliable.

(2) The LED driving power supply and dimming system adopts a single-ended flyback LED driving circuit, and the integrated chip makes the conversion efficiency of the circuit high.

(3) The LED driving power supply and dimming system adopts infrared remote control LED, and the infrared emitting part adopts the chip of uPD6121G chip transmitting code format to form a transmitting circuit, and the infrared receiving module adopts an integrated infrared receiver, which integrates infrared receiving Integrating and zooming in, the human-computer interaction is simple and convenient, and has strong practicability.

(4) Described a kind of LED drive power supply and dimming system, adopt chip type STC89C51 single-chip microcomputer as control core, intelligent degree is high, wherein temperature detection module monitors LED temperature in real time, generates an alarm under the LED abnormal state situation.

(5) The LED driving power supply and dimming system described above can remotely dim the LED according to individual requirements. The dimming range is wide, and it is suitable for various occasions.

Description of drawings

Figure 1 is a block diagram of the overall structure of the LED drive power supply and dimming system.

Figure 2 shows the main circuit of the LED drive power supply and dimming system.

Figure 3 is a circuit diagram of the LED drive power supply and the feedback loop of the dimming system.

Figure 4 is the minimum system diagram of SMT main control chip STC89C51.

Figure 5 is a liquid crystal display diagram.

Figure 6 is a circuit diagram of the infrared transmitter module.

Figure 7 is a circuit diagram of the infrared receiving module.

Figure 8 is a circuit diagram of the LED temperature sampling module.

Figure 9 is a circuit diagram of the buzzer alarm module.

Fig. 10 is a schematic diagram of infrared remote control codes "0" and "1".

Detailed ways

Below in conjunction with accompanying drawing, the utility model is further described.

As shown in Figure 1, the circuit of the utility model includes: AC input rectification filter unit, flyback conversion unit, output filter unit, constant current output unit, voltage sampling feedback unit, linear optocoupler isolation unit, STC89C51 single-chip microcomputer control module, Temperature sampling module, buzzer alarm module, liquid crystal display module, infrared sending module, infrared receiving module; the AC input rectification filter unit and flyback conversion unit are sequentially connected to the constant current output unit; the flyback conversion unit has 3 outputs , one way is +52V voltage for LED power supply voltage, one way is +12V voltage, and one way is +5V voltage for single-chip module power supply; there are 2 constant current output units, which drive two LED lights respectively; The network samples the voltage signal and inputs it to the reference terminal (Vref) of TL431CLP to control the shunt of the device from the cathode to the anode. This current directly drives the light-emitting part of the optocoupler U2, so when the output voltage tends to increase , Vref increases accordingly, causing the current flowing through TL431CLP to increase, so the photocoupler luminescence is strengthened, and the feedback voltage obtained by the photosensitive end is also greater. U2 will change the switching time of the MOSFET after receiving the increased feedback voltage, and the output voltage will fall back with the change, and then achieve the closed-loop control of the voltage to achieve stable voltage output; and the constant current output unit adopts MAX16822 step-down constant current high brightness LED driver, the output current is set by a high-side current detection resistor, and the dedicated PWM brightness adjustment input can realize pulse-type LED brightness adjustment with a wide brightness range; the liquid crystal display module displays the current brightness and temperature of the LED; the infrared emission module uses a handheld remote control to emit The infrared code is sent to the infrared receiving module; the infrared receiving module receives the transmitted infrared code to amplify and modulate, and sends it to the single-chip microcomputer in the form of an external interrupt; Device 2 generates PWM corresponding to the duty cycle to control the two LED lights.

As shown in Figure 2, in the main circuit, the 165V-265V AC is connected to the single-phase rectifier bridge after passing through the fuse F1, the piezoresistor RZ1, and the EMI unit (electromagnetic interference suppression unit). Among them, the EMI unit includes CX2, L3, and CX1. L3 is composed of two inductors connected to the live line and neutral line of the main input circuit respectively. The single-phase rectifier bridge is connected to the filter capacitor C7, and one end of the capacitor C7 is connected to an input of the rectifier bridge. One end, the other end is connected to the other end of the rectifier bridge and grounded (GND1). After the circuit is filtered, it is connected to the voltage detection resistor R6, and the other end of R6 is connected to the line voltage detection pin (L) of the TOP246Y chip. R6 is followed by an RCD buffer circuit, wherein the RCD buffer circuit is composed of R3, C3, D3, and CY1. R3 and C3 are connected in parallel to the cathode of D3, and the anode of D3 is connected to the drain pin (D) of the TOP246Y chip, and one end of CY1 Connect to pin 1 of transformer T1, and one end to pin 8 of T1. The upper end of RCD, that is, the upper end of R3 is connected to pin 1 of transformer T1. Pin 4 and pin 5 of T1 form an auxiliary winding, and pin 5 of T1 outputs a +12V voltage after being rectified and filtered by D5 and C13. There are four pins 7, 8, 9, and 10 on the secondary side of T1, and the winding composed of 7 pins and 8 pins is the main output circuit winding that supplies power to the LED lamp and outputs +52V voltage. Pin 7 of T1 is connected in series with a parallel network composed of R1, C1, and D2. This network is composed of R1 and C1 in series and connected in parallel with D2. The anode of D2 is connected to pin 7 of T1. The cathode of D2 is connected to the positive pole of polarity capacitor C4, and the negative pole of C4 is connected to pin 8 of T1. The positive pole of C4 is connected in series with an inductor L1, and then a polarized capacitor C5 and capacitor C6 are connected in parallel in the main output circuit, where the positive pole of C5 is connected to the other end of L1, and the negative pole of C5 is grounded (GND2). One end of C6 is connected to the positive pole of C5, and the other end is grounded (GND2). The winding composed of the 9-pin and 10-pin of the transformer T1 generates +5V voltage to supply power for the microcontroller. The 9-pin of T1 is connected in series with the anode of D4 and then connected to the positive pole of C10, while the negative pole of C10 and the 10-pin of T1 are connected to the ground (GND2). One end of C9 is connected to DZ1 and then connected to the cathode of D4, while the anode of DZ1 is connected to the other end of C9 and grounded (GND2). The external current limiting pin (X) of TOP246Y is connected to one end of resistor R13, and the other end of R13 is grounded (GND1). The frequency pin (F) and source pin (S) of TOP246Y are grounded (GND1) at the same time. The feedback signal is connected to the control pin (C) of TOP246Y and the parallel network composed of R11, C15, and C16. The parallel network is formed by connecting R11 and C16 in series and connecting C15 in parallel. The feedback signal is connected to one end of R11 and the other end of R11 Connect to the positive pole of C16, and the negative pole of C16 is grounded together with the other end of C15 (GND1). The +52V voltage generated by the main output circuit is connected to one end of the current-sensing resistor R2, and the other end of R2 is connected to the first pin 1 of the first MAX16822 (U1), and at the same time connected to the positive end of the first LED. The +52V voltage is connected to the cathode of D1, and the anode of D1 is connected to pins 5 and 6 of U1. Pins 5 and 6 of U1 are connected to an inductor L2 and then connected to the negative terminal of the first LED. The voltage of +52V is connected to pin 2 of U1. Pin 2 of U1 is connected to pins 3 and 4 through capacitor C8, and pins 3 and 4 are grounded (GND2). Pin 7 of U1 inputs a set of PWM from the microcontroller. Pin 8 of U1 is connected to one end of C2 and R4 at the same time, and the other end of C2 and R4 is grounded (GND2). The +52V voltage is connected to the negative pole of D6 and the No. 2 pin of the second MAX16822 (U5). The anode of D6 is connected to pins 5 and 6 of U5. Pins 5 and 6 of U5 are also connected to an inductor L4 and connected to the negative terminal of the second LED. The +52V voltage generated by the main output circuit is connected to one end of the current-sensing resistor R9, and the other end of R9 is connected to the No. 1 pin of U5, and at the same time connected to the positive end of the second LED. Pin 2 of U5 is connected to pins 3 and 4 through capacitor C17, and pins 3 and 4 are grounded (GND2). The No. 7 pin input of U5 comes from another set of PWM of the microcontroller. Pin 8 of U5 is connected to one end of C12 and R12 at the same time, and the other end of C12 and R12 is grounded (GND2).

As shown in Figure 3, the LED main output feedback loop is mainly composed of TL431CLP, optocoupler PC817A and its auxiliary circuits. Get the +52V reference voltage from the main circuit, and send the voltage on R14 to the reference terminal of TL431CLP after divided by R8 and R14. The reference end of TL431CLP is also connected to one end of capacitor C14, and the other end of C14 is connected to one end of R10 and C11. The other end of R10 and C11 is connected to the cathode of TL431CLP. The anode of the TL431CLP is grounded (GND2). The cathode of TL431CLP is also connected to the cathode of the light-emitting diode of photocoupler U3. The +52V voltage sampled from the anode of the main circuit C4 is connected to the anode of the light-emitting diode of the photocoupler U3 after passing through the resistor R5. A resistor R7 is also connected between the cathode and anode of the light-emitting diode of the photocoupler U3. The phototransistor collector of U3 is connected to the +12V power supply, and the emitter outputs a feedback signal.

As shown in Figure 4, the minimum system of STC89C51 microcontroller is composed of power supply, reset circuit and crystal oscillator circuit. The 5V power supply circuit is generated by the main circuit. The 5V power supply of the reset circuit is connected to one end of the switch S2, and the other end of the switch S2 is grounded after passing through the resistor R21. The anode of the capacitor C21 is connected to pin 4 of the microcontroller and the 5V power supply at the same time. Pin 38 of the microcontroller is connected to a 5V power supply. Pins 16 and 17 of the microcontroller are grounded (GND2). The 14th and 15th pins of the single chip microcomputer are respectively connected to the two ends of the crystal oscillator Y1, and at the same time, the two ends of Y1 are respectively connected to one end of the capacitors C21 and C22, and the other ends of C1 and C2 are grounded (GND2), forming a crystal oscillator module.

As shown in Figure 5, the STC89C51 liquid crystal display circuit is mainly composed of 12864 liquid crystal and its auxiliary circuits. The pins 1 and 20 of the 12864 LCD are grounded (GND2). Pin 2 is connected to a 5V power supply and one end of a 2KΩ sliding rheostat, and the other end of the sliding rheostat is grounded (GND2). Pin 3 is connected to the slider of the sliding rheostat. Pin 4 is connected to pin 11 of the MCU. Pin 5 is connected to pin 12 of the MCU. Pin 6 is connected to pin 10 of the MCU. Pins 7, 8, 9, 10, 11, 12, 13, and 14 of the 12864 LCD are respectively connected to pins 37, 36, 35, 34, 33, 32, 31, and 30 of the microcontroller. The 15th pin of the 12864 LCD is connected to the 13th pin of the microcontroller. Pins 16 and 18 of the 12864 LCD are left floating. Pins 17 and 19 of the 12864 LCD are connected to a 5V power supply. Pin 1 of the exclusion resistor P2 is connected to a 5V power supply. 2, 3, 4, 5, 6, 7, 8, and 9 of P2 are respectively connected to pins 37, 36, 35, 34, 33, 32, 31, and 30 of the microcontroller.

As shown in Figure 6, the infrared transmitter module is mainly composed of uPD6121G chip and its auxiliary circuit in the form of a handheld remote control. The remote control is powered by a 3V button battery. The VDD pin of uPD6121G is connected to the 3V power supply, and at the same time connected to the positive pole of capacitor C18, and the negative pole of C18 is grounded. The crystal oscillator Y2 is connected between the OSCI pin and OSCO pin of uPD6121G, and the two ends of Y2 are respectively connected to capacitors C19 and C20, and then grounded. The SEL pin of uPD6121G is connected to 3V power supply. The LMP pin of uPD6121G is connected to the cathode of the light-emitting diode, and the anode of the light-emitting diode is connected to the resistor R18 and then connected to the 3V power supply. The VSS pin of uPD6121G is grounded. The REM pin of uPD6121G is connected to the base of Q1, the collector of Q1 is connected to the cathode of the infrared light-emitting diode, the anode of the infrared light-emitting diode is connected to the 3V power supply, the emitter of Q1 is connected to one end of R20, and the other end of R20 One end is grounded. The KI pin and KI/O pin of uPD6121G form a 4×8 matrix keyboard corresponding to different codes. The CCS pin of uPD6121G is connected to the cathodes of D7 and D8, and the anodes of D7 and D8 are respectively connected to pin 0 and pin 3 of the KI/O pin. The 7th pin of the KI/O pin is connected to one end of R19, and the other end of R19 is connected to the 3V power supply.

As shown in Figure 7, the infrared receiving module is mainly composed of 1838 integrated infrared receiving head and its auxiliary circuit. The 1st pin of the 1838 is connected to the 8th pin P3.2 of the microcontroller, and the 2nd pin is grounded (GND2). The 5V power supply is connected to one end of R25, the other end of R2 is connected to one end of C23, and at the same time connected to pin 3 of 1838, and the other end of C23 is grounded (GND2).

As shown in Figure 8, the temperature acquisition module is mainly composed of DS18B20 and its auxiliary circuit. Pin 1 of DS18B20 is grounded (GND2), a resistor R22 is connected between pin 2 and pin 3, pin 3 of DS18B20 is connected to 5V voltage, and pin 2 of DS18B20 is connected to P2.4, pin 12 of the microcontroller.

As shown in Figure 9, the buzzer alarm module is mainly composed of buzzer BZ1 and its alarm circuit. The No. 13 pin P2.3 port of the microcontroller is connected to the base of the transistor Q5 through R23. The 5V voltage is connected to the emitter of Q5, the collector of Q5 is connected to one end of BZ1, and the other end of BZ1 is grounded (GND2) after passing through R24.

As shown in Figure 10, "0" and "1" of the remote control code of the infrared transmitting module. The infrared emission module includes keyboard matrix, code modulation, LED infrared transmitter. We choose the uPD6121G chip which is widely used and easy to decode to form the transmitting circuit. When the transmitter button is pressed, the remote control code will be sent out. The remote control code is different according to the key pressed. Line code, the combination of pulse width 0.565ms, interval 0.56ms, period 1.125ms represents binary "0"; the combination of pulse width 0.565ms, interval 1.685ms, period 2.25ms represents binary "1" .

Claims (9)

1. a LED driving power and light adjusting system, its feature comprises: the accessory power supply module that exchanges input rectifying filter unit, inverse-excitation converting unit, output filtering unit, constant current output unit, voltage sample feedback unit, light-coupled isolation unit, PWM adjustment module, STC89C51 single chip control module, LCD MODULE, DS18B20 temperature measurement module, buzzer warning module, infrared sending module, infrared receiving module, single-chip microcomputer, AC-input voltage is through after the rectification filtering unit rectifying and wave-filtering, be connected to the inverse-excitation converting unit, inverse-excitation converting unit generation+12V ,+5V ,+52V voltage, generation+52V voltage is after LC filtering, receive the constant current output unit, two LED lamps of the current source loads of constant current output unit, the reference edge that is input to the sampling feedback unit after LED power supply master output is sampled to voltage signal through potential-divider network is controlled the shunting of this device from the negative electrode to the anode, this electric current is again the luminous component that directly drives the light-coupled isolation unit, so when output voltage has the main trend of change, reference voltage terminal increases the electric current increase that causes flowing through TL431CLP thereupon, so luminous reinforcement of optocoupler, the feedback voltage that the sensitization end obtains is also just larger, TOP246Y is in the switching time of accepting after this becomes large feedback voltage to change MOSFET, output voltage falls after rise with change, infrared transmission module is used for producing the signal of regular coding to infrared receiving module, the information that the STC89C51 single chip control module receives infrared receiving module is decoded, the different coding sent according to infrared transmission module, two timers of single-chip microcomputer by inside produce two groups of adjustable PWM ripples of duty ratio and send to the brightness that the constant current output module is regulated LED, the temperature sampling module adopts DS18B20 to the LED temperature sampling, exceeds alarm value and reports to the police, LCD MODULE is used for showing two LED lamp ambient humidity, light and temperatures.

2. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described inverse-excitation converting unit adopts the single-end flyback switching power supply circuit, the simple efficiency of circuit is high, be applicable to requiring the power supply of many group direct voltage outputs, by single input power, use same magnetic circuit that many group direct-flow steady voltages are provided effectively.

3. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described PWM adjustment module adopts the TOP246Y chip to form voltage stabilizing circuit, its feature is that the PWM controller in high frequency switch power and MOSFET power switch pipe are integrated on same chip, it is a kind of two-in-one device, because the PWM controller is connected in shell with the MOSFET power switch pipe, line is extremely short, this has just improved the high frequency radiation phenomenon, improve the Electro Magnetic Compatibility of power supply, reduced the requirement of device to circuit-board laying-out and input bus transition.

4. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described Voltage Feedback module adopts TL431CLP directly to drive the luminous component of optocoupler U2, so when output voltage has the main trend of change, the TL431CLP reference voltage terminal increases the electric current increase that causes flowing through TL431CLP thereupon, so luminous reinforcement of optocoupler, the feedback voltage that the sensitization end obtains is also just larger, Voltage stabilizing module U2 is in the switching time of accepting after this becomes large feedback voltage to change MOSFET, and output voltage falls after rise with change.

5. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described constant current output unit adopts the MAX16822 chip to form constant-current drive circuit, MAX16822 is voltage-dropping type constant current high-brightness LED driver, output current is arranged by a flash current sense resistor, special-purpose PWM brightness regulation input can realize the pulsed LED brightness regulation of wide brightness range, by at DIM pin input pwm signal, realizing the LED brightness regulation, DIM input lower than the 0.6V logic level is forced the output of MAX16822 to drag down, thereby close the LED electric current, if must open the LED electric current, logic level on DIM must be higher than 2.8V.

6. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described single chip control module adopts the STC89C51 single-chip microcomputer to produce PWM to the LED brightness regulation, uses single-chip microcomputer to carry out software decode and export PWM to have low complex degree, low cost, the simple characteristics of control.

7. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described infrared transmission module adopts Infrared remote controller to control the duty cycle adjustment LED brightness of PWM, infrared remote control is convenient to miniaturization, cost is low, code modulating method is simple, low in energy consumption, be difficult for causing signal cross-talk, described system adopts the infrared remote control mode, in conjunction with LED light source, and any brightness adjusting, not only convenient but also energy-conservation within the specific limits.

8. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described single chip control module adopts timer 1 and the timer 2 of STC89C51 single-chip microcomputer to produce two groups of PWM that duty ratio is adjustable, control respectively two LED lamps, it is convenient, simple and reliable to control.

9. a kind of LED driving power and light adjusting system as claimed in claim 1, it is characterized in that: described temperature sampling module is sampled to the temperature of LED, if surpassed alarm value, buzzer gives the alarm.

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