Two-way constant current circuit and power supply device

Abstract

The invention discloses a two-way constant current circuit and a power supply device. The two-way constant current circuit comprises an LLC resonant converter circuit which is used for driving a current to carry out cycle conversion; a first rectifying circuit which is used for balancing voltage difference between LED light bars; and a constant current control circuit which is used for realizing constant current feedback through constant current feedback. The LLC resonant converter circuit inputs power supply currents to two paths of light bars. When voltage difference exists between the two paths of LED light bars, the first rectifying circuit carries out balancing through charge and discharge of a capacitor. The constant current feedback is carried out on the currents passing through the two paths of LED light bars by the constant current control circuit, thereby outputting the constant currents to the two paths of LED light bars. The invention also discloses a power supply device, comprising a current preprocessing circuit, a machine core power supply circuit and the two-way constant current circuit. According to the circuit and the device, voltage boost is not carried out by adoption of Boost in the constant current circuit, and the problems that serious loss occurs in the constant current and the cost is high are solved.

Description

technical field [0001] The invention relates to the technical field of constant current circuits, in particular to a dual-channel constant current circuit and a power supply device. Background technique [0002] In large-size TVs, there are generally many LED light strips. Usually, the LED backlight strips are integrated into two circuits through series connection. After the AC input, it passes through rectification and filtering and PFC circuit, and outputs two voltages through LLC half-bridge resonance, and one path directly supplies power. For the core part of the main board, the other circuit goes through two sets of Boost circuits to boost the voltage and constant current respectively, and then supplies power to the two LED strips. [0003] However, in this traditional method, because the high-power backlight drive part is boosted by a first-stage Boost, the loss is serious and the overall efficiency is low. Using two sets of Boost drives requires more components and hi...

AI Technical Summary

Problems solved by technology

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a dual-channel constant current circuit and a power supply device to solve the problem in the prior art of using Boost with high cost and serious loss to drive the constant current circuit

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