Circuit structure and method for improving DCDC chip performance

Abstract

According to the circuit structure and method for improving the performance of the DCDC chip, a comparator and a charge pump are arranged behind a power tube, when it is detected that the voltage of the source end and the drain end of the power tube in DCDC is larger than a given threshold voltage, the circuit structure can provide a negative voltage conveyed to the grid electrode of the power tube, and therefore the performance of the DCDC chip is improved. Therefore, the conduction impedance of the power tube is reduced, and the problems that when the DCDC chip is started, the starting speed is low due to the fact that the impedance of the power tube is too large, and when the input voltage is low, the loading capacity is low due to the fact that the impedance of the power tube is too large are solved.

Description

technical field [0001] The invention belongs to the technical field of switching power supplies, and in particular relates to a circuit structure and method for improving the performance of a DCDC chip. Background technique [0002] At this stage, the application of DCDC chips is becoming more and more extensive. The advantages and disadvantages of its performance in various aspects such as load capacity, startup speed and conversion efficiency, as well as the production cost of the chip itself determine the core competitiveness of the chip. During the startup process of the DCDC chip, the startup speed of the chip is often too slow due to the high on-resistance of the power tube, and the conversion efficiency is low during the startup process. There is a problem of low load capacity at low voltage; and in order to reduce the on-resistance of the power transistor, the area of ​​the power transistor needs to be increased, which leads to an increase in the production cost of t...

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