Dual-path power transmission circuit applied to on-chip DC-DC

Abstract

The invention provides a dual-path power transmission circuit applied to on-chip DC-DC, which relates to the technical field of integrated circuits. The dual-path power transmission circuit comprises a first power transmission path and a second power transmission path which are arranged in parallel; each of the first power transmission path and the second power transmission path comprises an isolation transformer, a driving circuit arranged on the primary side of the isolation transformer, and a rectifying circuit arranged on the secondary side of the isolation transformer; the rectifying circuit comprises four MOS tubes and two comparators; and the coil directions of the transformer of the first power transmission path and the transformer of the second power transmission path are opposite. Dual power transmission circuits are respectively provided with respective isolation transformers; the magnetic flux directions of the two isolation transformers are opposite, so that external electromagnetic radiation is counteracted, and the problem of electromagnetic interference (EMI) can be effectively reduced; and the receiving part of the power transmission circuit adopts four MOS tubes, so that the conduction voltage drop can be effectively reduced, and the conversion efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of integrated circuits, in particular to a dual-path power transmission circuit applied to on-chip DC-DC. Background technique [0002] The existing on-chip DC-DC isolation circuit mainly includes two parts, namely the power transmission circuit and the feedback signal isolation transmission circuit, such as figure 1 shown. The power supply comes from VIN, and the driving signal comes from the high-frequency clock signal of power control. After the driver drives the transformer T1, the energy is transferred from the primary side of the isolation transformer T1 to the secondary side. The rectification circuit rectifies the AC voltage to DC voltage, and then the capacitor C B Filter the DC voltage with an off-chip filter capacitor greater than 10uF to obtain a relatively stable V OUT Voltage. Among them, the simplest and commonly used rectification circuit is usually composed of four diodes, and Schottky di...

AI Technical Summary

Problems solved by technology

[0006] 1. When the isolation transformer T1 is working, the AC current flows through the coil of the isolation transformer T1 to generate magnetic flux, which will form magnetic field radiation, so it is not conducive to electromagnetic compatibility (EMC)

[0007] 2. For the rectifier circuit composed of four diodes D21, D22, D23, and D24, there will be two diodes connected in series at any time during operation, which will form a large voltage drop on the diode, and the voltage drop and current will form a large loss, which greatly reduces the conversion efficiency

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