High-voltage linear constant-power lamp control circuit

Abstract

The utility model relates to a high-voltage linear constant-power lamp control circuit, which comprises a power supply circuit for outputting voltage to a network label Vin, a dimming circuit provided with an LED lamp bead, a control circuit provided with a single chip microcomputer and a voltage detection circuit, the voltage detection circuit divides the voltage output by the network label Vin according to a proportion and then sends the voltage to the single chip microcomputer for AD detection, and the power supply circuit is connected with the control circuit. Once the input voltage exceeds a set value, the PWM wave output by the single-chip microcomputer reduces the duty ratio and reduces the current flowing through the LED lamp bead according to the rising proportion of the input voltage, because the input current is equal to the current flowing through the LED lamp bead, namely, the input current is reduced along with the rising of the input voltage, so that the input power is kept unchanged, and constant power control is realized; circuit elements are prevented from being damaged due to overpower and overheating, and the purpose of protecting the circuit is achieved. The circuit provided by the utility model can adjust the input power according to the change of the input voltage, so that the light source in the circuit is always in a constant-power working state.

Description

Technical Field

[0001] The utility model belongs to the field of lighting circuits, and in particular relates to a high-voltage linear constant-power lamp control circuit. Background Art

[0002] High-voltage linear dimming chips are now commonly used in high-voltage powered lamps. They use constant current technology to control the current flowing through the LED beads, thereby achieving a constant lumen output. However, in some areas, power supply fluctuations (for example, at night when many industrial enterprises are shut down, the grid voltage increases significantly due to no-load conditions), resulting in high input voltages for lamps. Lamp input power = input voltage squared / load impedance. Input power is proportional to the square of the input voltage. A voltage increase of a few volts will cause a sharp increase in power, significantly increasing the temperature of the entire lamp. This poses the risk of overheating and damage to the high-voltage linear dimming chip, leading to lamp failure. Utility Model Content

[0003] The purpose of the present utility model is to overcome the deficiencies in the prior art and thus provide a high-voltage linear constant-power lamp control circuit.

[0004] The technical solution adopted by the utility model to solve its technical problems is:

[0005] A high-voltage linear constant-power lamp control circuit includes a power supply circuit, a power supply circuit, a dimming circuit, a control circuit, and a voltage detection circuit. The power supply circuit consists of a fuse resistor 1, a varistor 1, a varistor 2, a safety capacitor, a resistor 1, a resistor 2, a rectifier tube, a bypass capacitor, and a diode 1. One end of the fuse resistor 1 is connected to the live wire, the other end of the fuse resistor 1, the one end of the varistor 1, the one end of the safety capacitor, and the one end of the resistor 1 are connected to the 4th pin of the rectifier tube, the 2nd pin of the rectifier tube, the other end of the resistor 1, the other end of the safety capacitor, and the other end of the varistor 1 are connected to the neutral line, the 3rd pin of the rectifier tube, the positive electrode of the diode 1, and the one end of the varistor 2 are output network labeled Vin, the 1st pin of the rectifier tube, the other end of the varistor 2, and the bypass capacitor are connected to the neutral line. The negative electrode of the bypass capacitor and one end of the resistor 2 are grounded respectively; the power supply circuit is composed of capacitor 1, capacitor 2, capacitor 3, capacitor 4, insurance resistor 2, voltage regulator diode, and power supply chip, among which the negative electrode of diode 1, the positive electrode of bypass capacitor and the other end of resistor 2 are connected to one end of insurance resistor 2, the other end of insurance resistor 2, the positive electrode of electrolytic capacitor 1, one end of capacitor 3 and the negative electrode of voltage regulator diode 1 are connected to the Vin pin of power supply chip, one end of capacitor 4, the positive electrode of electrolytic capacitor 2 and the Vout pin of power supply chip output working voltage +5V, the negative electrode of electrolytic capacitor 1, the other end of capacitor 3, the positive electrode of voltage regulator diode 1, the GND end of power supply chip, the other end of capacitor 4 and the negative electrode of electrolytic capacitor 2 are grounded respectively; the dimming circuit is connected to LED lamp beads 1, LED lamp bead 2, LED lamp bead 3, resistor 6, resistor 7, resistor 8, MOS tube, resistor, LED driver chip, capacitor 8, among which the cathode of diode 1, the positive electrode of bypass capacitor, the other end of resistor 2, and one end of resistor 8 are connected to the positive electrode of LED lamp bead 1, the negative electrode of LED lamp bead 1 is connected to the positive electrode of LED lamp bead 2, the negative electrode of LED lamp bead 2 is connected to the positive electrode of LED lamp bead 3, the negative electrode of LED lamp bead 3, the other end of resistor 8, and one end of capacitor 8 are connected to the 3rd pin of LED driver chip, the 1st pin of LED driver chip is connected to one end of resistor, the other end of resistor is connected to the drain of MOS tube, one end of resistor 6 and one end of resistor 7 are connected to the gate of MOS tube, the other end of resistor 7, the source of MOS tube, and capacitor 8 are connected. The other end of capacitor eight and pin 2 of the LED driver chip are grounded respectively; the control circuit is composed of a single-chip microcomputer, capacitor six, capacitor seven, resistor five, and a button, wherein pin 4 of the single-chip microcomputer is connected to the other end of resistor six, one end of capacitor six, one end of capacitor seven, and pin 1 of the single-chip microcomputer are connected to the working voltage +5V, pin 5 of the single-chip microcomputer is connected to one end of resistor five, pin 7 of the single-chip microcomputer is connected to one end of the button, pin 8 of the single-chip microcomputer, the other end of capacitor six, the other end of capacitor seven, and the other end of the button are grounded respectively; the voltage detection circuit is composed of resistor three, resistor four, and capacitor five, wherein one end of resistor three, one end of resistor four, and one end of capacitor five are connected to the other end of resistor five, the other end of resistor three is connected to the network label Vin, and the other end of resistor four and the other end of capacitor five are grounded respectively.

[0006] Preferably, the model of the power chip is 7150.

[0007] Preferably, the model of the LED driver chip is ZX9101HT.

[0008] Preferably, the model of the single chip microcomputer is FT61F131B-RB.

[0009] Compared with the prior art, the present invention has the following advantages and effects:

[0010] The circuit can adjust the input power according to the input voltage change, so that the light source in the circuit is always in a constant power working state. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Schematic diagram of a circuit of an embodiment of the utility model.

[0012] The drawings described herein are used to provide further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application. DETAILED DESCRIPTION

[0013] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0014] Example

[0015] like Figure 1 As shown, this embodiment includes a power supply circuit, a power supply circuit, a dimming circuit, a control circuit, and a voltage detection circuit. The power supply circuit is composed of a fuse resistor RF1, a varistor RV1, a varistor RV2, a safety capacitor CX1, a resistor R1, a resistor R2, a rectifier DB1, a bypass capacitor CE1, and a diode D1. One end of the fuse resistor RF1 is connected to the live wire, the other end of the fuse resistor RF1, one end of the varistor RV1, one end of the safety capacitor CX1, and one end of the resistor R1 are connected to pin 4 of the rectifier DB1. Pin 12 of the rectifier DB1, the other end of the resistor R1, the other end of the safety capacitor CX1, and the other end of the varistor RV1 are connected to the neutral wire. Pin 3 of the rectifier DB1, the positive electrode of the diode D1, and one end of the varistor RV2 are output to the network labeled Vin. Pin 11 of the rectifier DB1, the other end of the varistor RV2, the negative electrode of the bypass capacitor CE1, and one end of the resistor R2 are grounded.

[0016] like Figure 1As shown, the power supply circuit consists of capacitor 1 C1, capacitor 2 C2, capacitor 3 C3, capacitor 4 C4, fuse resistor 2 RF2, Zener diode ZD1, and power chip U2, wherein the cathode of diode 1 D1, the positive electrode of bypass capacitor CE1, and the other end of resistor 2 R2 are connected to one end of fuse resistor 2 RF2, the other end of fuse resistor 2 RF2, the positive electrode of electrolytic capacitor 1 C1, one end of capacitor 3 C3, and the cathode of Zener diode ZD1 D1 are connected to the Vin pin of power chip U2, one end of capacitor 4 C4, the positive electrode of electrolytic capacitor 2 C2, and the Vout pin of power chip U2 output the working voltage +5V, the cathode of electrolytic capacitor 1 C1, the other end of capacitor 3 C3, the positive electrode of Zener diode ZD1 D1, the GND terminal of power chip U2, the other end of capacitor 4 C4, and the negative electrode of electrolytic capacitor 2 C2 are grounded respectively.

[0017] like Figure 1 As shown, the dimming circuit consists of LED lamp bead 1 L1, LED lamp bead 2 L2, LED lamp bead 3 L3, resistor 6 R6, resistor 7 R7, resistor 8 R8, MOS tube Q1, resistor RS, LED driver chip U1, and capacitor 8 C8. Among them, the cathode of diode 1 D1, the positive electrode of bypass capacitor CE1, the other end of resistor 2 R2, and one end of resistor 8 R8 are connected to the positive electrode of LED lamp bead 1 L1, the negative electrode of LED lamp bead 1 L1 is connected to the positive electrode of LED lamp bead 2 L2, the negative electrode of LED lamp bead 2 L2 is connected to the positive electrode of LED lamp bead 3 L3, the negative electrode of LED lamp bead 3 L3, the other end of resistor 8 R8, and one end of capacitor 8 C8 are connected to pin 3 of LED driver chip U1, pin 1 of LED driver chip U1 is connected to one end of resistor RS, the other end of resistor RS is connected to the drain of MOS tube Q1, one end of resistor 6 R6 and one end of resistor R7 are connected to the gate of MOS tube Q1, the other end of resistor R7 and MOS tube Q1 The source, the other end of capacitor C8, and pin 2 of the LED driver chip U1 are grounded respectively.

[0018] like Figure 1 As shown, the control circuit consists of a single-chip microcomputer U3, a six-capacitor C6, a seven-capacitor C7, a five-resistor R5, and a button K1, wherein the 4th pin of the single-chip microcomputer U3 is connected to the other end of the six-resistor R6, one end of the six-capacitor C6, one end of the seven-capacitor C7, and the 1st pin of the single-chip microcomputer U3 are connected to the working voltage +5V, the 5th pin of the single-chip microcomputer U3 is connected to one end of the five-resistor R5, the 7th pin of the single-chip microcomputer U3 is connected to one end of the button K1, and the 8th pin of the single-chip microcomputer U3, the other end of the six-capacitor C6, the other end of the seven-capacitor C7, and the other end of the button K1 are grounded respectively.

[0019] like Figure 1 As shown, the voltage detection circuit is composed of a resistor R3, a resistor R4, and a capacitor R5, wherein one end of the resistor R3, one end of the resistor R4, and one end of the capacitor R5 are connected to the other end of the resistor R5, the other end of the resistor R3 is connected to the network label Vin, and the other end of the resistor R4 and the other end of the capacitor R5 are grounded respectively.

[0020] The working process of the above circuit is as follows: the voltage detection circuit divides the voltage output by the network label Vin in proportion, and then sends it to the single-chip microcomputer U3 for AD detection and calculation to obtain the value of the input voltage and detect the change of the input voltage. Once the input voltage exceeds the set value, the PWM wave output by the 4th pin of the single-chip microcomputer U3 reduces the duty cycle in proportion to the increase of the input voltage, thereby reducing the current flowing through the LED lamp bead. Because the input current is equal to the current flowing through the LED lamp bead, that is, as the input voltage increases, the input current is reduced, thereby keeping the input power unchanged, realizing constant power control, and avoiding damage to circuit components due to overpower and overheating, so as to achieve the purpose of protecting the circuit.

[0021] In this embodiment, the model of the power chip U2 is 7150, the model of the LED driver chip U1 is ZX9101HT, and the model of the microcontroller U3 is FT61F131B-RB.

[0022] The above contents described in this specification are merely examples of the present invention. Those skilled in the art of the present invention may make various modifications, additions, or substitute similar methods to the specific embodiments described, as long as they do not deviate from the contents of this specification or exceed the scope defined by the claims, and shall fall within the scope of protection of the present invention.

Claims

1. A high-voltage linear constant-power lamp control circuit, comprising a power supply circuit, a power supply circuit, a dimming circuit, a control circuit, and a voltage detection circuit, characterized in that: The power supply circuit consists of a fuse resistor 1, a varistor 1, a varistor 2, a safety capacitor, a resistor 1, a resistor 2, a rectifier, a bypass capacitor, and a diode 1. One end of the fuse resistor 1 is connected to the live wire, the other end of the fuse resistor 1, the one end of the varistor 1, the one end of the safety capacitor, and the one end of the resistor 1 are connected to pin 4 of the rectifier, pin 2 of the rectifier, the other end of the resistor 1, the other end of the safety capacitor, and the other end of the varistor 1 are connected to the neutral line, pin 3 of the rectifier, the positive electrode of the diode 1, and the one end of the varistor 2 are output network label Vin, and pin 1 of the rectifier, the other end of the varistor 2, the negative electrode of the bypass capacitor, and the one end of the resistor 2 are grounded respectively; The power supply circuit consists of capacitor 1, capacitor 2, capacitor 3, capacitor 4, fuse resistor 2, voltage regulator diode, and power supply chip. The cathode of diode 1, the positive electrode of bypass capacitor, and the other end of resistor 2 are connected to the first end of fuse resistor 2. The other end of fuse resistor 2, the positive electrode of electrolytic capacitor 1, the first end of capacitor 3, and the negative electrode of voltage regulator diode 1 are connected to the Vin pin of power supply chip. The first end of capacitor 4, the positive electrode of electrolytic capacitor 2, and the Vout pin of power supply chip output working voltage +5V. The negative electrode of electrolytic capacitor 1, the other end of capacitor 3, the positive electrode of voltage regulator diode 1, the GND terminal of power supply chip, the other end of capacitor 4, and the negative electrode of electrolytic capacitor 2 are grounded respectively. The dimming circuit consists of LED lamp bead 1, LED lamp bead 2, LED lamp bead 3, resistor 6, resistor 7, resistor 8, MOS tube, resistor, LED driver chip, and capacitor 8. The cathode of diode 1, the positive electrode of bypass capacitor, the other end of resistor 2, and one end of resistor 8 are connected to the positive electrode of LED lamp bead 1, the negative electrode of LED lamp bead 1 is connected to the positive electrode of LED lamp bead 2, the negative electrode of LED lamp bead 2 is connected to the positive electrode of LED lamp bead 3, the negative electrode of LED lamp bead 3, the other end of resistor 8, and one end of capacitor 8 are connected to pin 3 of LED driver chip, pin 1 of LED driver chip is connected to one end of resistor, the other end of resistor is connected to the drain of MOS tube, one end of resistor 6 and one end of resistor 7 are connected to the gate of MOS tube, the other end of resistor 7, the source of MOS tube, the other end of capacitor 8, and pin 2 of LED driver chip are grounded respectively. The control circuit consists of a single-chip microcomputer, capacitor six, capacitor seven, resistor five, and a button. Pin 4 of the single-chip microcomputer is connected to the other end of resistor six, one end of capacitor six, one end of capacitor seven, and pin 1 of the single-chip microcomputer are connected to the operating voltage +5V. Pin 5 of the single-chip microcomputer is connected to one end of resistor five, pin 7 of the single-chip microcomputer is connected to one end of the button, and pin 8 of the single-chip microcomputer, the other end of capacitor six, the other end of capacitor seven, and the other end of the button are grounded respectively. The voltage detection circuit consists of resistor three, resistor four, and capacitor five, where one end of resistor three, one end of resistor four, and one end of capacitor five are connected to the other end of resistor five, the other end of resistor three is connected to network label Vin, and the other ends of resistor four and capacitor five are grounded respectively.

2. The high-voltage linear constant-power lamp control circuit according to claim 1, characterized in that: The model of the power chip is 7150.

3. The high-voltage linear constant-power lamp control circuit according to claim 1, characterized in that: The model of the LED driver chip is ZX9101HT.

4. The high-voltage linear constant-power lamp control circuit according to claim 1, characterized in that: The model of the single chip microcomputer is FT61F131B-RB.

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