PTAT reference current source circuit with high-voltage power supply

Abstract

A PTAT reference current source circuit with high-voltage power supply comprises a current absorption module and a PTAT reference current generation module. The PTAT reference current generation module converts a temperature signal into a reference current in direct proportion to absolute temperature through clamping of a PNP type triode and outputs the reference current, and an LDMOS tube is adopted to replace a common MOS tube in a traditional structure, so that the circuit can adapt to high-voltage power supply. In view of the problem that the output reference current is influenced becausethe parasitic capacitance of a tube is increased and dv / dt noise of input voltage is more easily disturbed to a gate electrode of a fourth NMOS (N-channel metal oxide semiconductor) tube due to the fact that a common MOS (metal oxide semiconductor) is replaced by an LDMOS tube and the problem of lower opening speed caused by higher gate-source capacitance of the LDMOS tube, an LDMOS voltage-dividing current mirror and a capacitor noise filtering structure are further designed, so that high voltage can be borne, and the influence of dv / dt noise is reduced. Meanwhile, the current of the PTAT reference current generation module is extracted through the current absorption module, and the speed of establishing a stable state of a reference current is increased.

Description

technical field [0001] The invention belongs to the technical field of electronic circuits and relates to a PTAT reference current source circuit for high-voltage power supply. Background technique [0002] Reference current sources are widely used in analog circuit systems to determine system bias or provide reference current signals. In most cases, it is required that the output current of the reference current source needs to be indifferent to temperature or proportional to absolute temperature (PTAT). Taking the PTAT reference current source as an example, the PTAT reference current source will adjust the output reference current according to the temperature, which can compensate the influence of temperature on the circuit system to a certain extent. [0003] The basic principle of the PTAT reference current source is to collect the emitter junction voltage of the triode to adjust the output. Since the voltage of the emitter junction of the triode is closely related to ...

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Problems solved by technology

[0005] Aiming at the problem that the PTAT reference current source structure composed of ordinary MOS tubes cannot withstand high voltage in the traditional scheme, the present invention proposes a PTAT reference current source circuit for high-voltage power supply, and the PTAT reference current generation module adopts LDMOS tube step-down combined with PNP triode Generate a reference current proportional to the absolute temperature, which solves the problem that the traditional structure cannot withstand high voltage; at the same time, the invention designs the first capacitor C to filter the dv / dt noise caused by replacing the ordinary MOS with the LDMOS In addition to the noise caused by dv / dt; for the problem of slow turn-on speed of LDMOS tubes, the present invention designs a current absorption module to extract current from the PTAT reference current generation module, thereby accelerating the power-on start-up process

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