LED half-bridge circuit with feedback variable-frequency constant-current driving

Abstract

The invention discloses an LED half-bridge circuit with feedback variable-frequency constant-current driving function, comprising an input rectifying and filtering circuit, a half-bridge control circuit used for driving a chip in the chip based on one among an IR2151 drive chip, an IR2153 drive chip and an IR2155 drive chip, an isolation transformer and an output rectification filtering circuit. The LED half-bridge circuit further comprises a control chip power supply circuit for charging the electrolytic capacitor connected with the power port of the half-bridge control circuit. The input endof the control chip power supply circuit is connected with a half-bridge middle point of the half-bridge control circuit, and the output end is connected with the power end of the half-bridge controlchip. According to the invention, the structure is simple, and the output driving current is more stable. The method is suitable for driving the high-power LED.

Description

technical field [0001] The invention belongs to the technical field of electronic devices, and relates to an LED drive circuit, in particular to an LED half-bridge circuit with feedback variable frequency constant current drive. Background technique [0002] With the continuous consumption of global energy, electronic technology is constantly developing towards low energy consumption, and energy-saving technology is being rapidly promoted in electronic products. Among them, LED lighting lamps in electronic products have been widely used in many occasions such as street lighting and indoor lighting due to their high working efficiency and low energy consumption. Since the LED lighting lamp has a constant current working characteristic, in order to ensure the working advantage of the LED lighting lamp, an efficient and stable constant current LED driving circuit is the key. [0003] In the prior art, compared with the mainstream constant current drive circuit chips, IR2151, I...

AI Technical Summary

Problems solved by technology

However, in the traditional structure, the application circuits of the IR2151, IR2153, and IR2155 driver chips are as follows: figure 1 shown by figure 1 It can be seen that the power supply terminals of the above three driving chips are provided by the discharge of the electrolytic capacitor C2, and the electrolytic capacitor C2 needs to be charged by the current flowing through the resistor R1. In order to ensure the normal operation of the electrolytic capacitor C2, the charging current will be a large value. , and the large current will cause a large power consumption on the resistor R1, which is not conducive to energy saving and heat dissipation of the peripheral circuit of the chip

[0005] In addition, the above three driving chips do not have a direct control port for output current, so it is difficult to stably control the output constant current through this type of chip

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