Starting overshoot suppression circuit used for LDO

Abstract

The invention discloses a starting overshoot suppression circuit used for an LDO. The circuit comprises a first overshoot suppression circuit connected between a power end and an output end of an error amplifier of the LDO; the first overshoot suppression circuit comprises a first switch control unit and a voltage clamp unit which are in series connection, moreover, an enabling signal of the firstswitch control unit is obtained through inverting the enabling signal of the LDO and delaying for first predetermined time, thus, within the first predetermined time of starting of the LDO, through the voltage clamp unit, grid voltage of a power tube of the LDO is clamped to a first predetermined value, and grid source voltage of the power tube is maintained at a second predetermined value, so, current output to a load by the LDO is limited. With simpler circuit design, smaller circuit area and ultralow circuit power consumption, the starting overshoot suppression circuit provided by the invention realizes suppression of overshoot generated when the LDO starts, and thus, relatively small starting overshoot is realized.

Description

technical field [0001] The invention relates to the technical field of power management, in particular to a circuit for suppressing startup overshoot voltage of an LDO. Background technique [0002] With the increasing consumption of electronic products, portable electronic products such as smartphones, tablet computers, and notebook computers have become an indispensable part of people's daily life, and the strong growth of the above products has also made hybrid integrated circuits and SOC (System On chip (system-on-chip) develops rapidly, and often a chip needs multiple low-dropout linear regulators ("LDO" for short) to supply power to meet the low power consumption requirements of digital circuits. [0003] The life of the circuit working under the LDO voltage will be affected by the applied voltage. Excessive overshoot voltage during the startup of the LDO will seriously affect the life of the digital circuit, and may even cause breakdown of the device, so suppress the ...

AI Technical Summary

Problems solved by technology

However, additional proprietary circuits undoubtedly increase the circuit area and power consumption, which cannot meet the low power consumption and small area design requirements of most electronic products today.

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