Band-gap reference circuit and electronic device

Abstract

The invention discloses a band-gap reference circuit and an electronic device. The band-gap reference circuit comprises a first switch tube, a second switch tube, a first resistor, a control circuit and an operational amplifier circuit. The first switch tube and the second switch tube form a current mirror structure, and first control voltage is generated based on voltage input by a voltage input end; the control circuit generates a first regulating voltage and a second regulating voltage based on the first control voltage, and the operational amplifier circuit regulates the control end voltage of the second switching tube based on the first regulating voltage and the second regulating voltage until the band-gap reference circuit establishes a normal working point and outputs a reference voltage. According to the band-gap reference circuit, after the voltage is input into the voltage input end of the band-gap reference circuit, a zero degeneracy point can be gradually broken, the band-gap reference circuit enters a stable working state, and the reference voltage is output, so that self-starting is achieved, and an additional starting circuit is not needed.

Description

technical field [0001] The present application relates to the field of semiconductor integrated circuits, in particular to a bandgap reference circuit and an electronic device. Background technique [0002] With the development of semiconductor integrated circuits, its power supply system has been expanded from lithium batteries to button batteries or solar batteries. However, when a solar cell is used as a power source, its voltage fluctuates greatly and the voltage may drop to a relatively low value, so a bandgap reference circuit with low voltage, low power consumption, and high power supply rejection ratio (PSR) is required To ensure the stability of its output voltage. [0003] The basic principle of the bandgap reference circuit is to obtain a reference voltage with zero temperature coefficient by adding the voltage with positive temperature coefficient and the voltage with negative temperature coefficient with appropriate weight. However, in actual work, there are t...

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Problems solved by technology

However, in actual work, there are two degeneracy points of 0 and reference voltage in the bandgap reference circuit, and the existing bandgap reference circuit needs to add an additional start-up circuit to break the zero degeneracy point when starting up, so as to adjust to the normal operating point

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