High-voltage LDO (Low Dropout Regulator) circuit with clamping current limiting function

Abstract

The invention provides a high-voltage LDO (Low Dropout Regulator) circuit with a clamping current limiting function. The high-voltage LDO circuit is used for solving problems that a traditional high-voltage LDO is too large in area and not high in performance, an output driving tube is too high in gate-source voltage and prone to being damaged, and the output current of the LDO is limited. The circuit comprises three NMOS (N-channel Metal Oxide Semiconductor) tubes M1 to M3, four resistors R1 to R4, a capacitor C1, four voltage stabilizing diodes D1 to D4 and an error amplifier AMP; three voltage stabilizing diodes are connected in series at an input end to reduce an input high voltage to a low voltage range, a circuit can be designed by adopting a lower voltage-resistant device, a grid electrode and a source electrode of an output driving tube are connected with the voltage stabilizing diodes, and a purpose of limiting the output current is achieved by adopting the stabilized voltage value. A photomask layer is reduced while the driving capability is improved, the circuit is simple, and cost can be reduced.

Description

technical field [0001] The invention relates to electronic circuit technology, in particular to a high-voltage LDO circuit with clamping and current-limiting functions. Background technique [0002] LDO (Low Dropout Linear Regulator) is the core module in power management, which can realize voltage conversion and output stable power supply voltage. With the development of the scale of integrated circuits, the volume and weight of electronic equipment are getting smaller and smaller, which puts forward higher and higher requirements for the miniaturization of power supply circuits. If the area of ​​the LDO can be reduced well, the area of ​​the chip can be effectively reduced. This not only meets the requirement of miniaturization of the power supply circuit, but also controls the chip cost well. [0003] The basic structure of LDO includes: feedback resistor network, output drive tube and error amplifier. In order to meet the demand for operating voltage in high-voltage a...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problems of the above-mentioned traditional high-voltage LDO with too large area, low performance, too high gate-source voltage of the output drive tube and easy damage of the output current of the LDO, the present invention proposes A high voltage LDO circuit with clamp current limiting function

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