High-stability irradiation-resistant LED lamp constant current source driving circuit

Abstract

The invention discloses a high-stability radiation-resistant LED lamp constant-current source driving circuit, which comprises a surge protection circuit, an over-temperature and over-current protection circuit, a voltage transformation and rectification circuit and a constant-current source voltage regulation circuit, and is characterized in that the surge protection circuit adopts a gas discharge diode and a piezoresistor which are packaged by ceramics to improve the radiation resistance of the circuit; the surge protection circuit is connected with the transformation rectification circuit and is used for suppressing high-voltage pulses and shunting high voltage to realize overvoltage protection; the voltage transformation and rectification circuit and the over-temperature and over-current protection circuit are connected with the constant current source voltage regulation circuit, the voltage transformation and rectification circuit is used for transforming voltage and converting the voltage into direct current, and the over-temperature and over-current protection circuit cuts off a power supply when detecting abnormal high temperature or overlarge current to prevent the circuit from being damaged due to overheating or over-current; and the constant current source voltage regulating circuit is used for providing stable current output to drive the LED lamp. The LED lamp constant current source driving circuit has over-current, over-voltage and over-temperature protection functions while improving the irradiation resistance of the LED lamp constant current source driving circuit.

Description

Technical Field

[0001] This application relates to the technical field of constant current source drive circuits for radiation-resistant LED lamps, and specifically to a high-stability constant current source drive circuit for radiation-resistant LED lamps. Background Art

[0002] In the industrial development and application process of the nuclear energy industry, high-radioactive nuclear radiation exists in the production operation process of nuclear fuel. There are high-energy rays and particles such as gamma rays and neutron radiation in these radiation environments, which pose a serious threat to the normal operation of electronic circuits and integrated circuits. In traditional implementation schemes of radiation-resistant lamps, generally, the method of pulling the constant current source circuit farther away is adopted. However, this restricts the wiring of radiation-resistant lamps. If the wiring is too far or the wire diameter is too thin, the voltage drop on the line is too large, and there may be problems such as the LED lamp not being able to light up or insufficient LED drive power. Or the constant current source circuit of the radiation-resistant lamp is protected by a thick shielding metal. However, this increases the weight and size of the radiation-resistant lamp and also raises the cost of the radiation-resistant lamp.

[0003] Therefore, a high-stability and low-cost constant current source drive circuit for radiation-resistant LED lamps is expected by the market. Summary of the Invention

[0004] This application provides a high-stability constant current source drive circuit for radiation-resistant LED lamps, which is a high-stability and low-cost constant current source drive circuit for radiation-resistant LED lamps.

[0005] The technical solution adopted by this application to solve its technical problems is: to provide a high-stability constant current source drive circuit for radiation-resistant LED lamps, including: a surge protection circuit, an over-temperature and over-current protection circuit, a voltage transformation and rectification circuit, and a constant current source voltage regulation circuit. The surge protection circuit uses a gas discharge diode and a varistor in ceramic packaging to enhance the radiation resistance of the circuit. The surge protection circuit is connected to the voltage transformation and rectification circuit to suppress high-voltage pulses and achieve over-voltage protection by shunting high voltage. The voltage transformation and rectification circuit and the over-temperature and over-current protection circuit are connected to the constant current source voltage regulation circuit. The voltage transformation and rectification circuit is used to transform the voltage and convert the voltage into direct current. The over-temperature and over-current protection circuit cuts off the power supply when detecting abnormal high temperature or excessive current to prevent the circuit from being damaged due to overheating or overcurrent. The constant current source voltage regulation circuit is used to provide a stable current output to drive the LED lamp. This circuit can achieve the functions of surge protection, over-temperature and over-current protection, and constant current source without increasing costs while having good radiation resistance.

[0006] Preferably, the surge protection circuit includes a gas discharge diode GDT1, a gas discharge diode GDT2, a varistor M2, a varistor M3, and a varistor M4. One end of the gas discharge diode GDT1 is connected to the live wire of the power supply, and the other end is connected to the varistor M2. The other end of the varistor M2 and the varistor M3 are connected to the neutral wire of the power supply. The other end of the varistor M3 is connected to the gas discharge diode GDT2. The other end of the gas discharge diode GDT2 is connected to the varistor M4. The other end of the varistor M4 is connected to the live wire of the power supply. The gas discharge diode GDT2 is grounded. The gas discharge diode and the varistor are respectively connected in series and then connected between the neutral wire and the live wire, between the neutral wire and the ground, and between the live wire and the ground. In the high-stability radiation-resistant LED lamp constant current source drive circuit, a combination of a gas discharge diode and a varistor is used. The gas discharge diode discharges when the voltage across both ends exceeds the gas breakdown voltage inside the device, releasing the surge to limit the voltage and protecting the parallel circuit. The varistor clamps the voltage when the circuit withstands overvoltage, absorbs the excess current, and clamps the voltage between the neutral wire and the live wire within a safe range to protect the subsequent circuit. The varistor has a fast response in the overvoltage state but is prone to aging, affecting performance. The gas discharge diode has a slower response time in the overvoltage state but can withstand greater energy. The combination of the varistor and the gas discharge diode is connected in parallel between the neutral wire and the live wire. In the case of a long surge duration or a large current, the varistor can conduct quickly due to its voltage characteristics, and then the gas discharge diode is broken down under high voltage, releasing the surge to protect the subsequent circuit. Selecting ceramic-packaged gas discharge diodes and varistors for this section of the circuit has better radiation resistance.

[0007] Preferably, the step-down rectification circuit includes a toroidal transformer T1, a rectifier bridge circuit, a valley filling circuit, and a filter capacitor. The primary winding L1 of the toroidal transformer T1 is connected to the power supply. The secondary winding L2 of the toroidal transformer T1 is connected to the rectifier bridge circuit. The valley filling circuit is connected to the output end of the rectifier bridge circuit. The valley filling circuit is connected to the filter capacitor. The valley filling circuit is used to improve the power factor of the circuit. The filter capacitor is connected to the constant current source voltage regulation circuit to make the output of the bridge rectifier circuit more stable and smooth.

[0008] Preferably, the rectifier bridge circuit includes diodes D4, D5, D9, and D10. The secondary winding L2 of the toroidal transformer T1 is connected to the positive electrodes of diodes D4 and D5. The negative electrodes of diodes D4 and D5 are connected together. The negative electrode of diode D9 is connected to the positive electrode of diode D4. The positive electrode of diode D9 is connected to the positive electrode of diode D10. The negative electrode of diode D10 is connected to the positive electrode of diode D5. The rectifier bridge circuit converts the AC voltage output by the toroidal transformer T1 into a pulsating DC voltage.

[0009] Preferably, the valley filling circuit includes capacitor C3, capacitor C12, diode D6, diode D7 and diode D8. One end of capacitor C3 is connected to the negative electrode of diode D5, the other end of capacitor C3 is connected to the negative electrode of diode D8, the positive electrode of diode D8 is connected to capacitor C12, the other end of capacitor C12 is connected to the positive electrode of diode D6, the negative electrode of diode D6 is connected to capacitor C3, and diode D7 is connected to capacitor C3 and diode D6 respectively.

[0010] Preferably, the filter capacitor includes capacitor C6, capacitor C7, capacitor C8, capacitor C9 and capacitor C10. Capacitor C6, capacitor C7, capacitor C8, capacitor C9 and capacitor C10 are connected in parallel between capacitor C12 and diode D6. The filter capacitor is used to smooth the pulsating DC voltage after rectification and provide a relatively stable DC output.

[0011] Preferably, the over-temperature and over-current protection circuit includes relay SW1, diode D1, resistor R1, thermistor M1 and MOS transistor Q1 made of SiC material. Resistor R1 and thermistor M1 are connected in series and connected between DC outputs V+ and V-. The voltage dividing node of thermistor M1 and resistor R1 is connected to the G terminal of MOS transistor Q1. The S terminal of MOS transistor Q1 is connected to V-. The D terminal of MOS transistor Q1 is connected to V+ through series-connected relay SW1 and diode D1. The over-temperature and over-current protection circuit adjusts the output voltage to ensure that it is stable at the required value.

[0012] Preferably, the constant current source voltage regulating circuit is composed of resistor R2, resistor R3, resistor R4, resistor R5, capacitor C13, MOS transistor Q2 made of SiC material and MOS transistor Q3 made of SiC material. Resistor R2 and capacitor C13 are connected in series and connected to V+ and V-. The voltage dividing point of resistor R2 and capacitor C13 is connected to the D terminal of MOS transistor Q3. The voltage dividing point of resistor R2 and capacitor C13 is connected to the G terminal of MOS transistor Q2 through resistor R3. MOS transistor Q2 is connected to the negative electrode of the LED lamp. The S terminal of MOS transistor Q2 is connected to V- through resistor R5. The S terminal of MOS transistor Q3 is connected to V-. The G terminal of MOS transistor Q3 is connected to the S terminal of MOS transistor Q2 through resistor R4.

[0013] Preferably, the gas discharge diode GDT1 is externally connected to the live wire of the power supply through fuse F1. The surge protection circuit is connected to the step-down rectification circuit through the filter circuit. The filter circuit includes capacitor C1, capacitor C11 and capacitor C4. One end of capacitor C1 is connected to the live wire of the power supply, the other end of capacitor C1 is connected to capacitor C11, the other end of capacitor C11 is connected to the neutral wire of the power supply, capacitor C4 is connected between the neutral wire and the live wire, and capacitor C1 is grounded. A fuse F1 is placed at the input end for over-current protection to prevent the circuit from being damaged due to short circuit or other faults.

[0014] Preferably, the filter circuit is connected to the step-down rectification circuit through a filter voltage stabilization circuit. The filter voltage stabilization circuit outputs a stable power supply to the step-down rectification circuit. The filter voltage stabilization circuit includes an inductor L1, a capacitor C2, a capacitor C5, and a capacitor C14. One end of the inductor L1 is connected to the power supply, and the other end of the inductor L1 is respectively connected to the capacitor C2 and the capacitor C14. The capacitor C2 and the capacitor C14 are connected. The capacitor C5 is connected to the capacitor C2 and the capacitor C14. The capacitor C2 is grounded. The filter circuit is used to reduce the noise and interference in the input power supply.

[0015] The substantial effect of this application is that while this high-stability radiation-resistant LED lamp constant current source drive circuit has good radiation resistance, it realizes the functions of surge protection, over-temperature and over-current protection, and constant current source through circuit structure design. After testing, it is actually measured that without shielded metal protection, this circuit can meet a dose rate of 1000 Gy / h and reach an accumulated dose of 1 MGy. After irradiation, the output current capacity of the constant current source decreases by less than 2%, and the ripple increases by less than 5%, which fully meets the design application requirements. Description of the Drawings

[0016] Figure 1 is the circuit diagram of the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 2 is the circuit diagram of the surge protection circuit of the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 3 is the circuit diagram of the rectifier bridge circuit of the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 4 is the circuit diagram of the valley filling circuit of the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 5 is the circuit diagram of the filter capacitor of the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 6 is the circuit diagram of the over-temperature and over-current protection circuit of the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 7 is the circuit diagram of the constant current source voltage regulation circuit of the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 8 is the current waveform diagram output by the toroidal transformer T1 in the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 9 is the current waveform diagram after rectification by the rectifier bridge circuit in the high-stability radiation-resistant LED lamp constant current source drive circuit of this application; Figure 10It is the current waveform diagram after voltage regulation by the constant current source voltage regulation circuit in the high-stability radiation-resistant LED lamp constant current source drive circuit of the present application. Specific Embodiments

[0017] The following further specifically describes the technical solution of the present application through specific embodiments.

[0018] As Figure 1-6 shown, an embodiment of the high-stability radiation-resistant LED lamp constant current source drive circuit of the present application. In this embodiment, the high-stability radiation-resistant LED lamp constant current source drive circuit includes: a surge protection circuit, an over-temperature and over-current protection circuit, a voltage transformation and rectification circuit, and a constant current source voltage regulation circuit.

[0019] The surge protection circuit includes gas discharge diodes GDT1, GDT2, varistors M2, M3, and M4. One end of gas discharge diode GDT1 is connected to the live wire of the power supply, and the other end is connected to varistor M2. The other end of varistor M2 and varistor M3 are connected to the neutral wire of the power supply. The other end of varistor M3 is connected to gas discharge diode GDT2. The other end of gas discharge diode GDT2 is connected to varistor M4. The other end of varistor M4 is connected to the live wire of the power supply. Gas discharge diode GDT2 is grounded. Among them, the gas discharge diode is a ceramic-encapsulated gas discharge diode. The ceramic-encapsulated gas discharge diode and the varistor cooperate to have better radiation resistance. The varistors and gas discharge diodes are respectively connected in series and then connected between the neutral wire and the live wire, between the neutral wire and the ground, and between the live wire and the ground. When there is a long-duration or large-current surge, the varistor can quickly conduct due to its voltage characteristics, and then the gas discharge diode is broken down under high voltage to release the surge to protect the subsequent circuit.

[0020] Gas discharge diode GDT1 is externally connected to the live wire of the power supply through fuse F1. The surge protection circuit and the voltage transformation and rectification circuit are connected through a filtering circuit to achieve the filtering function. The filtering circuit includes capacitors C1, C11, and C4. One end of capacitor C1 is connected to the live wire of the power supply, the other end of capacitor C1 is connected to capacitor C11, the other end of capacitor C11 is connected to the neutral wire of the power supply, capacitor C4 is connected between the neutral wire and the live wire, and capacitor C1 is grounded.

[0021] The filtering circuit and the voltage transformation and rectification circuit are connected through a filtering and voltage regulation circuit. The filtering and voltage regulation circuit outputs a stable power supply to the voltage transformation and rectification circuit. The filtering and voltage regulation circuit includes inductor L1, capacitors C2, C5, and C14. One end of inductor L1 is connected to the power supply, the other end of inductor L1 is respectively connected to capacitors C2 and C14. Capacitors C2 and C14 are connected. Capacitor C5 is connected to capacitors C2 and C14, and capacitor C2 is grounded.

[0022] The step-down rectifier circuit includes a toroidal transformer T1, a rectifier bridge circuit, a valley-fill circuit, and a filter capacitor. The primary winding L1 of the toroidal transformer T1 is connected to the power supply, the secondary winding L2 of the toroidal transformer T1 is connected to the rectifier bridge circuit, the valley-fill circuit is connected to the output end of the rectifier bridge circuit, the valley-fill circuit is connected to the filter capacitor, and the valley-fill circuit is used to improve the power factor of the circuit.

[0023] The rectifier bridge circuit includes diodes D4, D5, D9, and D10. The secondary winding L2 of the toroidal transformer T1 is connected to the anodes of diodes D4 and D5. The cathodes of diodes D4 and D5 are connected together. The cathode of diode D9 is connected to the anode of diode D4, the anode of diode D9 is connected to the anode of diode D10, and the cathode of diode D10 is connected to the anode of diode D5. A direct current is output through the bridge rectifier circuit composed of diodes.

[0024] The valley-fill circuit includes capacitors C3, C12, diodes D6, D7, and D8. One end of capacitor C3 is connected to the cathode of diode D5, the other end of capacitor C3 is connected to the cathode of diode D8, the anode of diode D8 is connected to capacitor C12, the other end of capacitor C12 is connected to the anode of diode D6, the cathode of diode D6 is connected to capacitor C3, and diode D7 is connected to capacitor C3 and diode D6 respectively.

[0025] The filter capacitor includes capacitors C6, C7, C8, C9, and C10. Capacitors C6, C7, C8, C9, and C10 are connected in parallel between capacitor C12 and diode D6. Filtering is performed using capacitors to make the output of the bridge rectifier circuit more stable and smooth.

[0026] The over-temperature and over-current protection circuit includes a relay SW1, a diode D1, a resistor R1, a thermistor M1, and a MOS transistor Q1 made of SiC material. Resistor R1 and thermistor M1 are connected in series and connected between the DC outputs V+ and V-. The voltage-dividing node of thermistor M1 and resistor R1 is connected to the G terminal of MOS transistor Q1. The S terminal of MOS transistor Q1 is connected to V-, and the D terminal of MOS transistor Q1 is connected to V+ through a series connection of relay SW1 and diode D1. Since the resistance value of thermistor M1 will increase as the temperature rises, a suitable thermistor is selected to sense the temperature change and form an over-temperature and over-current protection circuit with MOS transistor Q1 and relay SW1.

[0027] The specific implementation principle is as follows: The over-temperature and over-current protection circuit serves as the switch for the output of the high-stability radiation-resistant LED lamp constant-current source driver circuit. When V+ and V- outputs are stable, since the thermistor M1 and the high-power resistor R1 are connected in series to form a voltage-dividing circuit, the voltage at the voltage-dividing point Vgs = Vdc * M1 / (M1 + R1), where Vdc is the voltage difference between V+ and V-. By selecting appropriate resistance values, Vgs is made higher than the threshold voltage, causing the MOS transistor Q1 to conduct and the relay SW1 to close, enabling the normal output of the high-stability radiation-resistant LED lamp constant-current source driver circuit. Conversely, when Vgs is lower than the threshold voltage, the MOS transistor Q1 does not conduct, the relay SW1 opens, and the high-stability radiation-resistant LED lamp constant-current source driver circuit shuts down its output.

[0028] When the temperature of the thermistor M1 rises, its resistance value increases, causing the voltage Vgs across the resistor R1 to gradually decrease. When the temperature exceeds the threshold voltage, Vgs becomes lower than the threshold voltage, the MOS transistor Q1 disconnects, and at this time the relay SW1 closes, shutting down the output of the high-stability radiation-resistant LED lamp constant-current source driver circuit, and the temperature inside the LED lamp drops. When the temperature of the thermistor M1 returns to normal, the relay will be reopened to enable the normal output of the high-stability radiation-resistant LED lamp constant-current source driver circuit, thus achieving over-temperature and over-current protection.

[0029] The thermistor M1 is installed closely to the LED lamp. When the high-stability radiation-resistant LED lamp constant-current source driver circuit experiences over-current, the temperature of the LED lamp rises sharply. The thermistor M1 senses the temperature increase and its resistance value increases, causing the voltage Vgs across the resistor R1 to be lower than the threshold voltage. At this time, the MOS transistor will be controlled to disconnect the relay SW1, cutting off the input to the LED lamp, thus achieving over-temperature and over-current protection.

[0030] The constant-current source voltage-regulating circuit consists of the resistor R2, resistor R3, resistor R4, resistor R5, capacitor C13, the MOS transistor Q2 made of SiC material, and the MOS transistor Q3 made of SiC material. The resistor R2 and the capacitor C13 are connected in series between V+ and V-. The voltage-dividing point of the resistor R2 and the capacitor C13 is connected to the D terminal of the MOS transistor Q3. The voltage-dividing point of the resistor R2 and the capacitor C13 is connected to the G terminal of the MOS transistor Q2 through the resistor R3. The MOS transistor Q2 is connected to the negative terminal of the LED lamp. The S terminal of the MOS transistor Q2 is connected to V- through the resistor R5. The S terminal of the MOS transistor Q3 is connected to V-. The G terminal of the MOS transistor Q3 is connected to the S terminal of the MOS transistor Q2 through the resistor R4.

[0031] The key to this circuit achieving constant current lies in using the MOS transistor Q2 of the SIC process to conduct and form a stable voltage. When the MOS transistor operates in the saturation region, it is also called the constant current region or the amplification region. In this region, the drain current Id of the MOS transistor reaches the saturation value and basically does not change with Vds. Vds is the voltage between the drain and source of the MOS transistor and is only determined by Vgs. Vgs is the voltage between the gate and source. Therefore, it can be used as a constant current source. The required current can be set through the resistor R5, and the current of this circuit can be maintained constant through the feedback mechanism of the MOS transistor Q3, without being affected by the load and voltage.

[0032] When the required output current is I, the size of the resistor R5 can be calculated to set the required current. The calculation formula is as follows: I = IQ2 = VQ3gs / R5 = (VQ3gs(th) + X1) / R5.

[0033] Among them, the values of X1 and VQ3gs(th) can be obtained by referring to the MOS data manual. VQ3gs is the voltage between the gate and source of the MOS transistor Q3. By adjusting the resistance value of the resistor R5, the output size of the high-stability radiation-resistant LED lamp constant current source drive circuit can be adjusted.

[0034] It should be noted that in the circuit, in order to further ensure reliability, we choose tantalum capacitors with good "self-healing" characteristics to design the circuit. The self-healing ability of tantalum capacitors mainly stems from the particularity of their internal structure, especially the design of the manganese dioxide cathode layer. During the operation of the capacitor, if there are defects or flaws in the dielectric layer, the current will concentrate and flow through these areas, resulting in a local temperature increase. When the temperature exceeds a certain threshold, manganese dioxide will release oxygen and transform into manganese trioxide with a higher resistivity. This transformation can limit the further passage of current, thus preventing the further expansion of the defective area. This characteristic plays a good role in ensuring the reliability of the capacitor during radiation damage.

[0035] As Figure 7-9 shown, testing the circuit of this application found that in the case of no shielding metal protection, the above circuit can meet a cumulative dose of 1MGy at a dose rate of 1000Gy / h. After irradiation, the output current capacity of the constant current source decreases by less than 2%, and the ripple increases by less than 5%, which fully meets the design application requirements.

[0036] The above-described embodiments are only a preferred solution of this application and do not impose any form of limitation on this application. There are other variations and modifications without exceeding the technical solutions described in the claims.

Claims

1. A high-stability radiation-resistant LED lamp constant current source drive circuit, characterized in that: include: Surge protection circuit, over-temperature and over-current protection circuit, transformer rectification circuit and constant current source voltage regulation circuit, The surge protection circuit uses a ceramic-encapsulated gas discharge diode and a varistor to improve the circuit's radiation resistance. The surge protection circuit is connected to a transformer and rectifier circuit to suppress high-voltage pulses and shunt the high voltage to achieve overvoltage protection. The transformer rectifier circuit and the over-temperature and over-current protection circuit are connected to the constant current source voltage regulating circuit. The transformer rectifier circuit is used to transform the voltage and convert the voltage into direct current. The over-temperature and over-current protection circuit cuts off the power supply when abnormally high temperature or excessive current is detected to prevent the circuit from being damaged due to overheating or overcurrent. The constant current source voltage regulator circuit is used to provide a stable current output to drive the LED lamp.

2. The high-stability radiation-resistant LED lamp constant current source driving circuit according to claim 1, characterized in that: The surge protection circuit includes a gas discharge diode GDT1, a gas discharge diode GDT2, a varistor M2, a varistor M3 and a varistor M4. One end of the gas discharge diode GDT1 is connected to the live wire of a power supply, and the other end is connected to the varistor M2. The other end of the varistor M2 and the varistor M3 are connected to the neutral wire of the power supply. The other end of the varistor M3 is connected to the gas discharge diode GDT2. The other end of the gas discharge diode GDT2 is connected to the varistor M4. The other end of the varistor M4 is connected to the live wire of the power supply. The gas discharge diode GDT2 is grounded. The varistor and the gas discharge diode are combined to release surges to protect the subsequent circuits.

3. The high-stability radiation-resistant LED lamp constant current source drive circuit according to claim 1 or 2, characterized in that: The transformer rectifier circuit includes a toroidal transformer T1, a rectifier bridge circuit, a valley filling circuit and a filter capacitor. The primary winding L1 of the toroidal transformer T1 is connected to a power supply, the secondary winding L2 of the toroidal transformer T1 is connected to the rectifier bridge circuit, the valley filling circuit is connected to the output end of the rectifier bridge circuit, the valley filling circuit is connected to the filter capacitor, the valley filling circuit is used to improve the power factor of the circuit, and the filter capacitor is connected to the constant current source voltage regulation circuit.

4. The high-stability radiation-resistant LED lamp constant current source drive circuit according to claim 1 or 2, characterized in that: The over-temperature and over-current protection circuit includes a relay SW1, a diode D1, a resistor R1, a thermistor M1 and a MOS tube Q1 made of SiC material. The resistor R1 and the thermistor M1 are connected in series and connected between the DC output V+ and V-. The voltage dividing node of the thermistor M1 and the resistor R1 is connected to the G level of the MOS tube Q1, the S level of the MOS tube Q1 is connected to V-, and the D level of the MOS tube Q1 is connected to V+ through the series relay SW1 and the diode D1. The relay SW1 is connected to the constant current source voltage regulation circuit.

5. The high-stability radiation-resistant LED lamp constant current source drive circuit according to claim 1 or 2, characterized in that: The constant current source voltage regulating circuit includes a resistor R2, a resistor R3, a resistor R4, a resistor R5, a capacitor C13, a MOS tube Q2 made of SiC material, and a MOS tube Q3 made of SiC material. The resistor R2 and the capacitor C13 are connected in series to V+ and V-, the voltage dividing point of the resistor R2 and the capacitor C13 is connected to the D level of the MOS tube Q3, the voltage dividing point of the resistor R2 and the capacitor C13 is connected to the G level of the MOS tube Q2 through the resistor R3, the MOS tube Q2 is connected to the negative pole of the LED lamp, the S level of the MOS tube Q2 is connected to V- through the resistor R5, the S level of the MOS tube Q3 is connected to V-, the G level of the MOS tube Q3 is connected to the S level of the MOS tube Q2 through the resistor R4, and the LED lamp is connected to the over-temperature and over-current protection circuit.

6. The high-stability radiation-resistant LED lamp constant current source driving circuit according to claim 3, characterized in that: The rectifier bridge circuit includes a diode D4, a diode D5, a diode D9 and a diode D10, the secondary winding L2 of the toroidal transformer T1 is connected to the anodes of the diodes D4 and D5, the cathodes of the diodes D4 and D5 are connected, the cathode of the diode D9 is connected to the anode of the diode D4, the anode of the diode D9 is connected to the anode of the diode D10, and the cathode of the diode D10 is connected to the anode of the diode D5.

7. The high-stability radiation-resistant LED lamp constant current source driving circuit according to claim 6, characterized in that: The valley filling circuit includes capacitor C3, capacitor C12, diode D6, diode D7 and diode D8. One end of capacitor C3 is connected to the cathode of diode D5, the other end of capacitor C3 is connected to the cathode of diode D8, the anode of diode D8 is connected to capacitor C12, the other end of capacitor C12 is connected to the anode of diode D6, the cathode of diode D6 is connected to capacitor C3, and diode D7 is connected to capacitor C3 and diode D6 respectively.

8. The high-stability radiation-resistant LED lamp constant current source driving circuit according to claim 7, characterized in that: The filter capacitor includes a plurality of capacitors, and the plurality of capacitors are connected in parallel between the capacitor C12 and the diode D6.

9. The high-stability radiation-resistant LED lamp constant current source driving circuit according to claim 2, characterized in that: The gas discharge diode GDT1 is connected to the live wire of the power supply through the fuse F1, and the surge protection circuit is connected to the transformer rectifier circuit through the filter circuit. The filter circuit includes capacitor C1, capacitor C11 and capacitor C4. One end of capacitor C1 is connected to the live wire of the power supply, and the other end of capacitor C1 is connected to capacitor C11. The other end of capacitor C11 is connected to the neutral wire of the power supply. Capacitor C4 is connected between the neutral wire and the live wire, and capacitor C1 is grounded.

10. The high-stability radiation-resistant LED lamp constant current source driving circuit according to claim 9, characterized in that: The filter circuit is connected to the transformer and rectifier circuit through a filter and voltage stabilizing circuit. The filter and voltage stabilizing circuit outputs a stable power supply to the transformer and rectifier circuit. The filter and voltage stabilizing circuit includes an inductor L1, a capacitor C2, a capacitor C5 and a capacitor C14. One end of the inductor L1 is connected to the power supply, and the other end of the inductor L1 is respectively connected to the capacitor C2 and the capacitor C14. The capacitor C2 is connected to the capacitor C14, the capacitor C5 is connected to the capacitor C2 and the capacitor C14, and the capacitor C2 is grounded.

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