Control chip of switch power supply and switch power supply

Abstract

The invention provides a control chip and a switch power supply, wherein the control chip is electrically connected with a switch tube; the control chip comprises a voltage collecting module, an error amplifying module, a time collecting module and a constant-voltage constant-current module; the voltage collecting module is used for collecting the feedback voltage of the output voltage; the error amplifying module is used for comparing and amplifying the feedback voltage collected by the voltage collecting module and a reference voltage, and outputting an error voltage; the time collecting module is used for acquiring a demagnetization time signal according to the feedback voltage collected by the voltage collecting module; and the constant-voltage constant-current module is used for collecting a peak value current feedback signal of the switch tube, regulating the frequency and duty ratio of a control signal according to the demagnetization time signal of the time collecting module, the error voltage of the error amplifying module and the collected peak value current feedback signal, as well as controlling the switch tube according to the control signal. The control chip and the switch power supply with the control chip can lower the system standby power consumption.

Description

technical field [0001] The invention belongs to the technical field of electronic information, and in particular relates to a control chip of a switching power supply and a switching power supply. Background technique [0002] At present, almost all household appliances need to use low-voltage DC power supply for the main power supply or control part of the power supply. However, due to the loss of voltage transmission in the power grid, currently only 220V (110V in some countries) AC power supply can be provided. Therefore, a high-efficiency, cost-effective AC-DC (AC-DC) converter becomes an indispensable part. Traditional AC-DC devices are usually implemented with linear converters, but linear converters are being phased out rapidly due to their huge size, heavy weight, low conversion efficiency and no longer obvious cost advantages. In the current AC-DC Among conversion devices, switching power adapters have become the absolute mainstream. In order to meet the requireme...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem of high standby power consumption in the switching power supply system in the prior art, the present invention provides a control chip and a switching power supply with the control chip, which can reduce the system standby power consumption

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