A low-dropout linear regulator circuit, a low-dropout linear regulator and an electronic chip

Abstract

The invention provides a low-dropout linear voltage regulator circuit, a low-dropout linear voltage regulator and an electronic chip. The low-dropout linear voltage regulator circuit includes an error amplifier circuit, a buffer circuit, an output power tube, a feedback network, and an anti-saturation circuit, wherein, The first end of the anti-saturation circuit is connected to the buffer circuit, and the second end of the anti-saturation circuit is connected to the output end of the low-dropout linear voltage regulator circuit. The anti-saturation circuit is used to correct the BC junction of the output power tube when the output power tube is in a saturated state The voltage is clamped, and the present invention also provides a low-dropout linear voltage regulator and an electronic chip, which can realize that when the output power tube reaches a saturated state, the BC junction voltage of the output power tube is clamped, so that the output power tube BC The junction voltage is kept at a fixed voltage value to prevent further saturation of the output power tube into a deep saturation state, thereby avoiding the problems of reduced circuit efficiency, heat generation, affecting performance or even burning the circuit due to the deep saturation of the output power tube.

Description

technical field [0001] The invention relates to the technical field of integrated circuits, in particular to a low-dropout linear voltage regulator circuit, a low-dropout linear voltage regulator and an electronic chip. Background technique [0002] Low-dropout regulator (Low-dropout regulator, LDO), also known as low-dropout regulator, low-dropout regulator, is used to provide a stable DC voltage power supply. Compared with general linear DC regulators, LDO can It works with a smaller input and output voltage difference and is widely used in electronic products. [0003] The negative-voltage-to-negative-voltage LDO chips made by bipolar process usually use NPN transistors as output power tubes. The tube goes into deep saturation. At this time, since the output power tube enters a deep saturation state, a large current of up to 100mA will flow through the base of the output power tube. On the one hand, the large current does not contribute to the output current, on the oth...

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Problems solved by technology

[0005] In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a low dropout linear voltage regulator circuit, a low dropout linear voltage regulator and an electronic chip, which are used to solve the problem that the output power tube cannot be prevented from entering a deep saturation state in the related art. The problem

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