TWM590341U - LED driving structure - Google Patents

Abstract

An LED driving structure includes an LED module electrically connected, a power supply circuit, a voltage stabilizing circuit, a temperature compensation loop and a gallium nitride field effect transistor, wherein the power supply circuit is used to supply current to LED module; the voltage stabilizing circuit includes a rectifying diode, a resistor and an acceptor diode, and is connected to the gate electrode of the gallium nitride field effect transistor through a temperature compensation loop to provide a stable voltage; temperature The compensation loop includes at least one resistor, a thermistor, and a transistor connected to the gate of the GaN field effect transistor, which is used to enable the LED module to maintain its power when the voltage changes and the temperature changes change.

Description

LED drive structure

This creation is related to LEDs, especially an LED drive circuit structure.

Light-emitting diode (LED) has been widely used after the technology has gradually improved and the production cost has been reduced due to the advantages of traditional light sources, such as high efficiency, long life, easy to break, fast response, and high reliability. For lighting purposes. Especially in today's market, high-voltage and low-current high-voltage LEDs are mostly used. High-voltage LEDs are placed on a single chip with an LED matrix, which has the function of adjusting the voltage and current, so that the LED light source can achieve a single output light source effect due to a single chip. It is used to improve optical design, simplify LED packaging process, and improve luminous efficiency. However, high-voltage LEDs have high requirements for voltage stability, especially the switching elements in the drive circuit, that is, metal oxide semiconductor field effect transistors (MOSFETs), but there is a new switching element, the gate of the gallium nitride field effect transistor. (GaNFET) is rising, but the new GaNFET has the advantages of higher efficiency, faster switching frequency and ultra-small package size, but it requires relatively strict gate-source voltage drive, so the conventional LED drive circuit is usually A voltage stabilizing circuit will be set up to stabilize the operating voltage of the LED and thus maintain its power.

However, the LED will generate a lot of heat energy during operation to increase the temperature, and due to the nature of its semiconductor material, the voltage and power will be reduced. In order to reduce the volume, the high-voltage LED and the driving circuit are integrated on a circuit board, and the LED emits light. The high heat generated will inevitably affect the electronic components of the driving circuit, but if you do not want to solve the effect of the heat generated by the LED lamp on the surrounding electronic components, then no good voltage regulator circuit can make up for the attenuated power, so that the LED lamp Work performance is still low. In view of this, how to improve the above-mentioned problems is the primary issue for this creation.

The main purpose of this creation is to provide an LED driving structure, which uses a temperature compensation circuit in the voltage stabilizing circuit to keep the LED at a fixed power during voltage fluctuations and temperature fluctuations, and to prevent the LED from being driven due to the influence of temperature on the drive. A situation in which the electronic components of a circuit cause a power drop.

Another purpose of this creation is to provide an LED driving structure, in which a temperature compensation circuit is designed in the voltage stabilizing circuit to provide a more stable and stricter voltage to the gate of the GaN field effect transistor to improve the GaN The field-effect transistor has better working efficiency, so that the LED can maintain a constant power.

To achieve the foregoing purpose, the present invention provides an LED driving structure, which includes an LED module electrically connected, a power supply circuit, a voltage stabilizing circuit, a temperature compensation circuit, and a gallium nitride field effect transistor, among them: The power supply circuit is used to supply current to the LED module; The voltage stabilizing circuit includes a rectifying diode, a resistor and an acceptor diode, and is connected to the gallium nitride field effect transistor through the temperature compensation circuit to provide a stable voltage; The temperature compensation circuit includes at least one resistor, a thermistor, and a transistor connected to the gate of the gallium nitride field effect transistor to keep the power of the LED module unchanged when generating heat after being energized .

Preferably, the voltage stabilizing circuit further includes a capacitor.

Preferably, the LED module is made by chip direct packaging technology.

In one embodiment, the LED module is a high-voltage LED for vehicles.

However, it is not difficult to obtain an in-depth understanding from the detailed description and drawings of the selected embodiments below for the above purposes and advantages of this creation.

Please refer to the first figure, which shows the LED driving structure provided for the creation, including an LED module 1 with electrical connection, a power supply circuit 2, a voltage stabilizing circuit 3, a temperature compensation circuit 4 and a nitrogen GaAs field effect transistor 5 (GaN FET). In this embodiment, the LED module 1 is a high-voltage LED for vehicles, and is made by chip on board (COB) technology.

According to the above, the power supply circuit 2 includes a plurality of diodes for supplying current to the LED module 1. In this embodiment, the power supply circuit 2 has a plurality of rectifier diodes for supplying a certain current Give the LED module. The voltage stabilizing circuit 3 includes a rectifying diode D1, a resistor R1, a capacitor C1, and an acceptor diode ZD1, and is connected to the gate electrode of the gallium nitride field effect transistor 5 to provide stable Voltage. The temperature compensation circuit 4 includes two resistors R2, R3, a thermistor NTC1 and a transistor Q1 connected to the voltage stabilizing circuit 3, and the transistor Q1 is connected to the gate electrode of the gallium nitride field effect transistor 5, It is used to compensate the voltage when the temperature changes.

When the LED module 1 is energized, it generates heat energy and the temperature rises. At this time, the voltage of the LED module 1 drops, and the on-resistance of the gallium nitride field effect transistor 5 rises, which lowers the current and causes the overall power to fall. However, with the above circuit structure, after the temperature rises, the resistance value of the thermistor NTC1 decreases, so that the voltage of the transistor Q1 and the gallium nitride field effect transistor 5 rises, which in turn increases the current. The attenuation situation is offset, and the working efficiency of the LED module 1 can be maintained.

The characteristic of this creation is that the temperature compensation circuit 4 makes the temperature change not cause the result of voltage instability. Not only can it provide a stable voltage to the LED module 1, but also the gallium nitride field effect transistor 5 can drive the LED with a stable voltage Module 1.

However, the disclosures of the above embodiments are only used to illustrate the creation, not to limit the creation, so the replacement of equivalent elements should still belong to the scope of the creation.

In summary, those skilled in the art can understand that this creation can indeed achieve the aforesaid objectives, and in fact have complied with the provisions of the Patent Law, and file an application in accordance with the law.

１‧‧‧LED module 2‧‧‧Power supply circuit 3‧‧‧Regulatory circuit 4‧‧‧Temperature compensation circuit 5.‧‧‧GaN FET C1‧‧‧Capacitor D1‧‧‧rectifier diode NTC1‧‧‧Thermistor Ｑ１‧‧‧Transistor R1, R2, R3 ‧‧‧ resistance ＺD１‧‧‧Inspected diode

Figure 1 is a schematic diagram of the circuit created.

1‧‧‧LED module

2‧‧‧Power supply circuit

3‧‧‧ Voltage stabilizing circuit

4‧‧‧Temperature compensation circuit

5‧‧‧GaN FET

C1‧‧‧Capacitor

D1‧‧‧rectifier diode

NTC1‧‧‧Thermistor

Q1‧‧‧Transistor

R1, R2, R3 ‧‧‧ resistance

ZD1‧‧‧Inspect Diode

Claims (5)

An LED driving structure includes an LED module electrically connected, a power supply circuit, a voltage stabilizing circuit, a temperature compensation loop and a gallium nitride field effect transistor, wherein: The power supply circuit is used to supply current to the LED module; The voltage stabilizing circuit includes a rectifying diode, a resistor and an accepting diode, and is connected to the gate electrode of the gallium nitride field effect transistor through a temperature compensation loop to provide a stable voltage; The temperature compensation loop includes at least one resistor connected to the voltage stabilizing circuit, a thermistor, and a transistor connected to the gate of the gallium nitride field effect transistor to compensate its voltage when the temperature changes, so that the LED The module keeps its power unchanged when it generates heat after being powered on. The LED driving structure according to claim 1, wherein the voltage stabilizing circuit further includes a capacitor. The LED driving structure according to claim 1, wherein the power supply circuit has a plurality of rectifying diodes for supplying a certain current to the LED module. The LED driving structure according to claim 1, wherein the LED module is made by a chip direct packaging technology. The LED driving structure according to claim 1, wherein the LED module is a high-voltage LED for vehicles.

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