Positive and negative charge pump control

Patent metadata

Field	Value
Publication number	US-2023198386-A1
Application number	US-202318168936-A
Country	US
Kind code	A1
Filing date	Feb 14, 2023
Priority date	Jan 24, 2020
Publication date	Jun 22, 2023
Grant date	—

Abstract

A voltage supply circuit and a method for controlling a voltage supply circuit are provided. The voltage supply circuit includes a positive charge pump stage that generates a positive voltage and a negative charge pump stage that generates a negative voltage. The voltage supply circuit also includes a control stage that compares a voltage representative of the negative voltage with a reference voltage and causes a slope of the positive voltage to decrease when the voltage representative of the negative voltage exceeds the reference voltage.

First claim

1 . A voltage supply circuit, comprising:
a first charge pump stage configured to generate a first voltage having a first polarity; a second charge pump stage configured to generate a second voltage having a second polarity that is different from the first polarity; an oscillator configured to output a clock signal to the first charge pump stage; a regulator configured to supply the oscillator with a regulated voltage; and a control stage configured to:
receive a voltage representative of a magnitude of the second voltage;
compare the voltage representative of the magnitude of the second voltage with a first reference voltage; and
in response to determining that the magnitude of the second voltage exceeds the first reference voltage, cause the regulator to decrease the regulated voltage.

2 . The voltage supply circuit of claim 1 , wherein the control stage is configured to:
in response to determining that the magnitude of the second voltage does not exceed the first reference voltage, refrain from causing the regulator to decrease the regulated voltage.

3 . The voltage supply circuit of claim 1 , wherein the regulator is configured to:
receive a voltage representative of a magnitude the first voltage; compare the voltage representative of the magnitude of the first voltage with a second reference voltage; and control the regulated voltage based on comparing the voltage representative of the magnitude of the first voltage with a second reference voltage.

4 . The voltage supply circuit of claim 3 , wherein the regulator is configured to control the regulated voltage by:
decreasing the regulated voltage in response to determining that the magnitude of the voltage representative of the first voltage exceeds the second reference voltage.

5 . The voltage supply circuit of claim 3 , wherein the regulator is configured to control the regulated voltage by:
increasing the regulated voltage in response to determining that the magnitude of the voltage representative of the first voltage does not exceed the second reference voltage.

6 . The voltage supply circuit of claim 1 , wherein the second polarity is an opposite polarity to the first polarity.

7 . The voltage supply circuit of claim 1 , comprising:
a voltage divider configured to produce the voltage representative of the magnitude of the second voltage.

8 . A method, comprising:
generating, by a first charge pump stage, a first voltage having a first polarity; generating, by a second charge pump stage, a second voltage having a second polarity that is different from the first polarity; outputting, by an oscillator, a clock signal to the first charge pump stage; supplying, by a regulator, a regulated voltage to the oscillator; comparing a voltage representative of a magnitude of the second voltage with a first reference voltage; and in response to determining that the magnitude of the second voltage exceeds the first reference voltage, causing the regulator to decrease the regulated voltage.

9 . The method of claim 8 , comprising:
in response to determining that the magnitude of the second voltage does not exceed the first reference voltage, refraining from causing the regulator to decrease the regulated voltage.

10 . The method of claim 8 , comprising:
receiving a voltage representative of a magnitude the first voltage; comparing the voltage representative of the magnitude of the first voltage with a second reference voltage; and controlling the regulated voltage based on comparing the voltage representative of the magnitude of the first voltage with a second reference voltage.

11 . The method of claim 10 , wherein controlling the regulated voltage includes:
decreasing the regulated voltage in response to determining that the magnitude of the voltage representative of the first voltage exceeds the second reference voltage.

12 . The method of claim 10 , wherein controlling the regulated voltage includes:
increasing the regulated voltage in response to determining that the magnitude of the voltage representative of the first voltage does not exceed the second reference voltage.

13 . The method of claim 8 , wherein the second polarity is an opposite polarity to the first polarity.

14 . A system, comprising:
a circuit configured to receive first and second voltages; and a voltage supply circuit including:
a first charge pump stage configured to generate the first voltage having a first polarity;
a second charge pump stage configured to generate the second voltage having a second polarity that is different from the first polarity;
an oscillator configured to output a clock signal to the first charge pump stage;
a regulator configured to supply the oscillator with a regulated voltage; and
a control stage configured to:
receive a voltage representative of a magnitude of the second voltage;
compare the voltage representative of the magnitude of the second voltage with a first reference voltage; and
in response to determining that the magnitude of the second voltage exceeds the first reference voltage, cause the regulator to decrease the regulated voltage.

15 . The system of claim 14 , wherein the control stage is configured to:
in response to determining that the magnitude of the second voltage does not exceed the first reference voltage, refrain from causing the regulator to decrease the regulated voltage.

16 . The system of claim 14 , wherein the regulator is configured to:
receive a voltage representative of a magnitude the first voltage; compare the voltage representative of the magnitude of the first voltage with a second reference voltage; and control the regulated voltage based on comparing the voltage representative of the magnitude of the first voltage with a second reference voltage.

17 . The system of claim 16 , wherein the regulator is configured to control the regulated voltage by:
decreasing the regulated voltage in response to determining that the magnitude of the voltage representative of the first voltage exceeds the second reference voltage.

18 . The system of claim 16 , wherein the regulator is configured to control the regulated voltage by:
increasing the regulated voltage in response to determining that the magnitude of the voltage representative of the first voltage does not exceed the second reference voltage.

19 . The system of claim 14 , wherein the second polarity is an opposite polarity to the first polarity.

20 . The system of claim 14 , wherein the voltage supply circuit includes:
a voltage divider configured to produce the voltage representative of the magnitude of the second voltage.

Assignees

• St Microelectronics Int Nv
• St Microelectronics Srl

Inventors

• Rana Vikas
• Pasotti Marco
• De Santis Fabio

Classifications

• G11C5/145 Primary

  Applications of charge pumps; Boosted voltage circuits; Clamp circuits therefor (G11C5/141 takes precedence) · CPC title

• H02M3/07 Primary

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

• H02M3/071

  adapted to generate a negative voltage output from a positive voltage source · CPC title

• H02M1/32

  Means for protecting converters other than automatic disconnection · CPC title

• H02M1/36

  Means for starting or stopping converters · CPC title