Low-power-consumption high-voltage starting circuit having undervoltage lockout function

Abstract

The invention belongs to the field of analog integrated circuits, and particularly provides a low-power-consumption high-voltage starting circuit having the undervoltage lockout function. The circuit includes an enabled / undervoltage lockout circuit, a high-voltage-resisting PTAT current generating circuit and a secondary power supply voltage-generating circuit. After the voltage of a power supply reaches a predetermined value, the enabled / undervoltage lockout circuit provides bias current for a PTAT circuit; when the voltage of the power supply is very small, and a follow-up circuit is locked out and made to stop work; the high-voltage-resisting PTAT current generating circuit provides stable bias current for the follow-up circuit, and the stable bias current is finally output through an NPN pipe; the output voltage of the secondary power supply voltage-generating circuit is composed of the stable voltage of a voltage-regulator diode and the voltage of an base electrode and an emitting electrode of a bipolar transistor. The low-power-consumption high-voltage starting circuit can achieve not only the circuit starting function but also the undervoltage lockout function, the circuit is suitable for high voltage, and at the same time, the power consumption is very low, especially under the high voltage.

Description

technical field [0001] The invention belongs to the technical field of analog integrated circuits, in particular to a high-voltage start-up circuit with low power consumption and an undervoltage lockout function. Background technique [0002] In today's integrated circuit technology, both the start-up circuit and the undervoltage lockout circuit are indispensable modules. The starting circuit is to start the circuit quickly when the power is turned on, so that the starting of the circuit is not related to the power-on process, so that its working state is more stable. The undervoltage lockout circuit is more used to shut down the circuit when the power supply is insufficient or the power supply fails, that is, the power supply voltage is lower than the minimum operating power threshold set by the system. So as to protect the battery, reduce unnecessary power consumption and avoid misoperation. Both are necessary conditions to ensure system stability. [0003] Today, some ...

AI Technical Summary

Problems solved by technology

like image 3 It is a traditional under-voltage lockout circuit. This circuit is not suitable for high voltage, the response speed is average, and the power consumption is large, especially when the voltage of the sampling terminal is relatively high.

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