High-precision linear voltage stabilizing circuit

Abstract

The invention relates to a high-precision linear voltage stabilizing circuit, which comprises a band-gap reference circuit, a power supply ripple suppression circuit and a soft start circuit, whereinthe input end of the power supply ripple suppression circuit is connected with an external input power supply voltage, the output end of the power supply ripple suppression circuit is connected with the input end of the band-gap reference circuit, the output end of the band-gap reference circuit outputs a reference voltage, and the soft start circuit is connected with the external input power supply voltage and the band-gap reference circuit; the band-gap reference circuit is used for generating reference voltage, the power supply ripple suppression circuit is used for suppressing power supplyripples so that the band-gap reference circuit does not change along with external input power supply voltage, and the soft start circuit converts the voltage stabilizing circuit from a zero-currentworking point state to a normal working point state. The high-precision linear voltage stabilizing circuit has the advantages of wide working voltage range, good temperature drift suppression capability, good power supply ripple suppression capability, low circuit complexity, low power consumption and small occupied area.

Description

technical field [0001] The invention relates to the technical field of integrated circuits, and more specifically relates to a high-precision linear voltage stabilizing circuit. Background technique [0002] The CMOS voltage reference is an indispensable key module in the system chip, and it is widely used in various analog chips such as operational amplifier bias circuits, ADCs, and power management. Especially in high-precision sensing circuits, an accurate bias circuit plays a vital role in improving the performance of the entire system. In order to provide a stable and high-precision bias for the entire analog front-end circuit, the voltage reference circuit usually pursues two important design indicators: temperature drift suppression capability and power supply ripple suppression capability. At the same time, it is necessary to take into account the complexity, power consumption and chip area of ​​the voltage reference circuit involved. As a general module, there are...

AI Technical Summary

Problems solved by technology

[0007] However, the aforementioned (1) traditional voltage reference circuit can meet basic applications, and is suitable for occasions where the system accuracy is not high, and its temperature drift suppression and power supply ripple suppression capabilities are average.

The voltage reference circuit in (2) above can work under the condition of power supply voltage lower than 1V, but because the bias current of the MOS transistor working in the sub-threshold region is very small, it is very vulnerable to transistor leakage current, circuit noise or other noise interference

At the same time, the working state of the MOS transistor in the sub-threshold region is extremely sensitive, and it is easy to leave the sub-threshold region under interference and cause the circuit to fail.

Power supply voltage noise immunity cross-

Although the voltage reference circuit in (3) above has an advantage in terms of chip area and power consumption, the switching noise introduced in total and the charge feedthrough effect of the MOS switch have an impact on the output of the reference voltage. At the same time, the power supply voltage ripple suppression ability also poor

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