A half-bridge circuit with ultra-wide range constant current that realizes regulation from 0v

Abstract

The invention discloses a half-bridge circuit with an ultra-wide range of constant current that can be adjusted from 0V. The half-bridge circuit includes a PFC control circuit, a PFC boost circuit, a half-bridge control circuit, a half-bridge main circuit and a transformer circuit, and an external power supply is input to the PFC. The boost circuit is boosted by the PFC boost circuit and output to the main circuit of the half-bridge, and then output to the transformer circuit after constant current processing by the main circuit of the half-bridge, and then output to supply power to the load after being transformed by the transformer circuit, the PFC control circuit controls the PFC The boost circuit works, and the half-bridge control circuit controls the work of the half-bridge main circuit. The circuit structure of the present invention is simple, without adding additional circuits, it can realize wide constant current range and small current change, and can make the output terminals be connected in any number from one LED lamp to multiple lamps.

Description

[0001] technical field [0002] The invention discloses a constant current circuit, in particular an ultra-wide range constant current half-bridge circuit which realizes 0V regulation. Background technique [0003] With the development of LED lighting technology, LED lighting devices are more and more widely used in people's daily life. Current LED lighting devices are usually driven by constant current sources. At present, the constant current range of conventional LED single-channel constant current sources using a half-bridge structure is relatively narrow. Generally, the lower limit voltage of the CV constant current voltage is only about 0.5-0.6 times the upper limit voltage. When the CV voltage goes down, or Not constant current, or the IC supply voltage will enter undervoltage protection, causing the output to shut down. Contents of the invention [0004] Aiming at the shortcoming that the constant current range of the half-bridge structure LED single-chann...

AI Technical Summary

Problems solved by technology

At present, the constant current range of conventional LED single-channel constant current sources using a half-bridge structure is relatively narrow. Generally, the lower limit voltage of the CV constant current voltage is only about 0.5-0.6 times the upper limit voltage. When the CV voltage goes down, either Not constant current, or the IC power supply voltage will enter the undervoltage protection, causing the output to shut down

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