Low dropout linear voltage regulator with wide input voltage range

Abstract

A low dropout linear voltage regulator with a wide input voltage range comprises an error amplifier, a power tube, a voltage division network, a bias module, a buffer stage, a feed-forward access, a dynamic sampling module and an output detection module. The source electrode of the power tube is connected with the input voltage of the low dropout linear voltage regulator, and the drain electrode of the power tube generates an output signal of the low dropout linear voltage regulator; the voltage division network divides the output signal of the low dropout voltage regulator to obtain a feedback signal; the bias module is used for providing bias; the error amplifier pre-amplifies the difference voltage of the feedback signal and the reference voltage and transmits the pre-amplified difference voltage to the buffer stage and the feed-forward access at the back stage, and the two paths with different speeds of the buffer stage and the feed-forward path are converged at the grid end of thepower tube to charge and discharge to control the voltage at the grid end of the power tube; the dynamic sampling module can improve the transient response speed of the system; and the output detection module is used for detecting whether output is normal in real time.

Description

technical field [0001] The invention belongs to the technical field of power supply management, and relates to a low-voltage linear voltage regulator, which can be used for power supply of internal circuits of chips. Background technique [0002] A low dropout regulator (Low Dropout Regulator, LDO) is an important type of circuit in a power management chip. It has the advantages of low cost, low noise, low power consumption, simple circuit structure and small occupied chip area, and is widely used in consumer electronics, medical electronics, aerospace and other fields. [0003] There is a lot of noise in the voltage input from the outside of the chip, so a stable, low-noise power supply is needed inside the chip to power the internal circuit. LDO is a good choice to power the internal circuit. LDO controls the power transistor by amplifying the error signal obtained through output feedback to provide output current to drive the load. Such as figure 1 As shown, the tradit...

AI Technical Summary

Problems solved by technology

Because of the large drift of the main pole Po, it is difficult to estimate the ESR with the frequency and temperature changes, which brings great difficulties to the stability design of the entire LDO, and the introduction of ESR is usually accompanied by a large voltage spike in the transient state , which deteriorates the transient characteristics of the LDO

Images