A DC-DC Converter Adaptive Dead Zone Generation Circuit Based on Zero-Voltage Startup

Abstract

The invention belongs to the technical field of electronic circuits, and relates to a DC-DC converter self-adaptive dead zone generation circuit based on zero-voltage startup. The adaptive dead zone generation circuit samples the load current of the DC-DC converter through the current sampling circuit, and converts it into voltage information, and obtains the sampled voltage as the input voltage of the integrator circuit; the integral control circuit carries out integration of the integrator circuit Control; finally, the waveform processing circuit processes the output waveform of the integrator circuit to obtain a power tube gate drive signal with an adaptive dead zone. The beneficial effect of the present invention is that it can effectively and adaptively provide the optimal dead time for the power tube according to the load variation of the DC-DC converter, so as to ensure the zero-voltage turn-on of the power tube. Compared with the traditional fixed dead zone circuit, the conduction loss of the switching tube is approximately zero, and the output waveform is more stable under different load conditions, which can effectively improve the efficiency of the DC-DC converter.

Description

Technical field [0001] The invention belongs to the technical field of electronic circuits, and relates to an adaptive dead zone generating circuit of a DC-DC converter based on zero voltage start. Background technique [0002] In the DC-DC converter, the on-resistance of the power tube is very small. If the two power tubes are turned on at the same time, there will be a low resistance path from the power supply to the ground, and the current flowing through the power tube will be very large, which can reach The ampere level greatly increases the power consumption of the chip, and in severe cases, the power tube and the entire chip will be seriously damaged. Therefore, a dead time is generally added between the two power tubes to prevent the high and low end power tubes of the same arm from being turned on at the same time during the working process. The usual approach is to use a fixed-length dead time. Its advantages are convenient and simple design and high reliability, but i...

AI Technical Summary

Problems solved by technology

The usual practice is to use a fixed length of dead time, which has the advantages of convenient and simple design and high reliability, but its disadvantages are also particularly obvious: fixed dead time will cause high and low power tubes to be turned off for a long time at the same time under light load In this case, it will affect the driven load voltage and current waveform, which will further lead to problems of low efficiency and poor stability

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