Band-gap reference circuit

Patent metadata

Field	Value
Publication number	US-10732662-B2
Application number	US-201816212080-A
Country	US
Kind code	B2
Filing date	Dec 6, 2018
Priority date	Jan 26, 2018
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

A band-gap reference circuit including a charge pump circuit and a reference circuit is disclosed. The charge pump circuit is powered by a supply voltage and thereby outputs a regulating voltage which is higher than the supply voltage and powers the reference circuit such that the reference circuit outputs a band-gap reference voltage. Powering the reference circuit with the regulating voltage that is made higher than the supply voltage by the charge pump circuit enables 1) normal operation of the band-gap reference circuit at the supply voltage that is lower than a lowest voltage required by the band-gap reference circuit; and 2) minimization (almost elimination) of fluctuations in the regulating voltage output from the charge pump circuit and hence a stable and more accurate band-gap reference voltage output from the band-gap reference circuit.

First claim

What is claimed is:

1. A band-gap reference circuit, comprising a charge pump circuit and a reference circuit, wherein the charge pump circuit is powered by a supply voltage and thereby outputs a regulating voltage which is provided to the reference circuit, wherein the regulating voltage is higher than the supply voltage and powers the reference circuit such that the reference circuit outputs a band-gap reference voltage, wherein the reference circuit comprises first to tenth transistors, a first triode and a second triode as well as a first resistor, and wherein:
each of the first and second transistors is implemented as a P-channel field-effect transistor, a source of the first transistor and a source of the second transistor coupled to the regulating voltage, a gate of the first transistor connected to a gate of the second transistor, a drain of the second transistor connected to the gate of the second transistor;
each of the third and fourth transistors is implemented as a P-channel field-effect transistor, a source of the third transistor connected to a drain of the first transistor, a source of the fourth transistor connected to the drain of the second transistor, a gate of the third transistor connected to a gate of the fourth transistor, a drain of the fourth transistor connected to the gate of the fourth transistor;
each of the fifth and sixth transistors is implemented as an N-channel field-effect transistor, a source of the fifth transistor connected to a drain of the third transistor, a source of the sixth transistor connected to the drain of the fourth transistor, a gate of the fifth transistor connected to a gate of the sixth transistor, a drain of the fifth transistor connected to the gate of the fifth transistor;
each of the seventh and eighth transistors is implemented as an N-channel field-effect transistor, a source of the seventh transistor connected to the drain of the fifth transistor, a source of the eighth transistor connected to a drain of the sixth transistor, a gate of the seventh transistor connected to a gate of the eighth transistor, a drain of the seventh transistor connected to the gate of the seventh transistor;
each of the ninth and tenth transistors is implemented as a P-channel field-effect transistor, a source of the ninth transistor coupled to the regulating voltage, a gate of the ninth transistor connected to the gate and the drain of the second transistor, a drain of the ninth transistor connected to a source of the tenth transistor, a gate of the tenth transistor connected to the gate and the drain of the fourth transistor;
a drain of the tenth transistor outputs a band-gap reference voltage which is feedback to a second input of the charge pump circuit;
each of the first triode and the second triode is implemented as a PNP triode, an emitter of the first triode directly connected to the drain of the seventh transistor, an emitter of the second triode coupled to a drain of the eighth transistor through the first resistor, a collector and a base of the first triode being both grounded, and a collector and a base of the second triode being both grounded.

2. The band-gap reference circuit of claim 1 , wherein the supply voltage is 1.2 V, the regulating voltage is 2.4 V and the band-gap reference voltage is 1.2 V.

3. The band-gap reference circuit of claim 1 , wherein the reference circuit further comprises a second resistor and a third triode which is implemented as a PNP triode, and wherein the second resistor is connected to a drain of the tenth transistor at one end and to an emitter of the third triode at the other end, and a collector and a base of the third triode are both grounded.

Assignees

• Wuhan Xinxin Semiconductor Mfg

Inventors

• Tang Yuan

Classifications

• G05F3/262

  using field-effect transistors only · CPC title

• G05F3/245

  producing a voltage or current as a predetermined function of the temperature · CPC title

• G05F3/247

  producing a voltage or current as a predetermined function of the supply voltage · CPC title

• G05F3/267 Primary

  using both bipolar and field-effect technology · CPC title

• H02M3/07

  using capacitors charged and discharged alternately by semiconductor devices with control electrode {, e.g. charge pumps} · CPC title