Multi-channel constant current circuit and lighting device
地域：
Shenzhen
摘要
A multi-channel constant current circuit and a lighting device are provided. The multi-channel constant current circuit is used to drive UVC LED to emit light, and includes a constant voltage circuit and a first number of linear constant current diodes. The constant voltage circuit includes a power input terminal, a power output terminal and a voltage regulation sub-circuit. The power input terminal is connected to the power output terminal through the voltage regulation sub-circuit, each of the linear constant current diodes is connected to the power output terminal, the linear constant current diode is used to connect a second number of UVC LEDs and keeps a working current of each UVC LED, and the voltage regulation sub-circuit is used for a constant output voltage.
說明書
The present disclosure relates to a driving field, in particular, to a multi-channel constant current circuit and a lighting device.
LED (Light-Emitting Diode, light-emitting diode) is a common light-emitting device with the advantages of high luminous efficiency and long working life. The sensitivity of LEDs to current is higher than the sensitivity to voltage. Conventional LED arrays are usually connected in a multi-series and multi-parallel manner, so that multiple LEDs share a positive electrode and are connected to a constant current source drive circuit.
However, C-band ultraviolet light-emitting diode (UVC LED) is a light-emitting device with high forward voltage, which requires high voltage accuracy. Multi-parallel and multi-series UVC LEDs have the technical features of high voltage and low current, and are not suitable for circuit designs in which positive and negative poles are shared. In addition, when the forward voltage of the UVC LED is floating, the current distributed by the power supply to each string of UVC LEDs in parallel is not uniform. Constant current source driving circuit cannot output constant current due to frequent adjustment of output power, which results in flicking and failure of UVC LED.
In view of the defects in the prior art, the purpose of the embodiments of the present disclosure is to provide a multi-channel constant current circuit and a lighting device to solve the problem that the UVC LED cannot be guaranteed to be in a constant voltage and constant current state.
The technical solution of the present disclosure is as follows.
權利要求
What is claimed is:1. A multi-channel constant current circuit used to drive UVC LED to emit light, the multi-channel constant current circuit comprising:a constant voltage circuit including a power input terminal, a power output terminal, and a voltage regulation sub-circuit; and a first number of linear constant current diodes; wherein the power input terminal is connected to the power output terminal through the voltage regulation sub-circuit, each of the first number of linear constant current diodes is connected to the power output terminal, the linear constant current diode is used to connect a second number of UVC LEDs and keeps a working current of each of the second number of UVC LEDs, and the voltage regulation sub-circuit is used for a constant output voltage. 2. The multi-channel constant current circuit according to claim 1 , wherein the voltage regulation sub-circuit includes a voltage controller, an inductor, a switch tube, a first resistor, and a voltage feedback branch;wherein one end of the inductor is connected to the power input terminal, another end of the inductor is correspondingly connected to the power output terminal and a first end of the switch tube, a second end of the switch tube is grounded through the first resistor, and the power output terminal is grounded through the voltage feedback branch; wherein a power supply pin of the voltage controller is connected to the power input terminal, a drive signal pin of the voltage controller is connected to a control terminal of the switch tube, a feedback voltage pin of the voltage controller is connected to the voltage feedback branch, a detection pin of the voltage controller is grounded through the first resistor, a ground pin of the voltage controller is grounded, and a switch pin of the voltage controller is used to receive a switch signal of the voltage controller. 3. The multi-channel constant current circuit according to claim 2 , wherein the constant voltage circuit further includes a Schottky diode;wherein an anode of the Schottky diode is correspondingly connected to the another end of the inductor and the first end of the switch tube, a cathode of the Schottky diode is connected to the power output terminal, and the Schottky diode is used to prevent a backflow of current at the power output terminal. 4. The multi-channel constant current circuit according to claim 3 , wherein the voltage feedback branch includes a second resistor and a third resistor, the cathode of the Schottky diode is grounded through the second resistor and the third resistor in sequence, and the feedback voltage pin of the voltage controller is connected to a node between the second resistor and the third resistor. 5. The multi-channel constant current circuit according to claim 2 , wherein the switch tube is an NMOS tube, a drain of the NMOS tube is connected to the inductor, a source of the NMOS tube is grounded through the first resistor, and a gate of the NMOS tube is connected to the drive signal pin of the voltage controller. 6. The multi-channel constant current circuit according to claim 1 , wherein the constant voltage circuit further includes a first filter circuit, and the power input terminal is grounded through the first filter circuit. 7. The multi-channel constant current circuit according to claim 6 , wherein the first filter circuit includes a first electrolytic capacitor and a first ceramic capacitor;wherein the power input terminal is grounded through the first electrolytic capacitor and the first ceramic capacitor respectively, the first electrolytic capacitor is used for a low-frequency filtering of the power input terminal, and the first ceramic capacitor is used for a high-frequency filtering at the power input terminal. 8. The multi-channel constant current circuit according to claim 1 , wherein the constant voltage circuit further includes a second filter circuit, and the power output terminal is grounded through the second filter circuit. 9. The multi-channel constant current circuit according to claim 8 , wherein the second filter circuit includes a second electrolytic capacitor and a second ceramic capacitor;wherein the power output terminal is grounded correspondingly through the second electrolytic capacitor and the second ceramic capacitor, the second electrolytic capacitor is used for a low-frequency filtering of the power output terminal, the second electrolytic capacitor is used for storing electrical charge, and the second ceramic capacitor is used for a high-frequency filtering at the power output terminal. 10. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 1 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 11. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 2 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 12. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 3 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 13. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 4 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 14. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 5 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 15. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 6 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 16. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 7 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 17. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 8 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups. 18. A lighting device, comprising:a UVC LED array; and the multi-channel constant current circuit according to claim 9 ; wherein the UVC LED array includes a third number of UVC LED string groups, each of the third number of UVC LED string groups includes the second number of UVC LEDs connected in series, and a linear constant current diode is correspondingly grounded through one of the UVC LED string groups.
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