Online Voltage Adjustment Circuit for Board Power Supply

• US 20190271999A1
• Filed: 05/17/2019
• Published: 09/05/2019
• Est. Priority Date: 11/17/2016
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Peng, Yunwu, Peng, Qi, Zhang, Xuejing
• Granted Patent: US 10,642,297 B2
• Time in Patent Office: Days
• CPC Class Codes: G05F 1/56 using semiconductor devices in series with the load as final control devices G05F1/461 takes precedence
• CPC Class Codes: G05F 1/575 characterised by the feedback circuit

Abstract

An online voltage adjustment circuit for a board power supply, where a first voltage division circuit is coupled in parallel to a first bias resistor, a second voltage division circuit is coupled in parallel to a second bias resistor, and a detection chip obtains an initial output voltage of the board power supply. Based on the initial output voltage and a preset voltage, a control chip controls a first switch on the first voltage division circuit to be on or off, and a second switch on the second voltage division circuit to be on or off. As a result, a feedback value of a feedback pin of the board power supply changes, and then an output voltage of the board power supply changes, thereby adjusting the output voltage of the board power supply.

Claims

1. An online voltage adjustment circuit for a board power supply, comprising:

a first switch;

a first bias resistor, wherein a first end of the first bias resistor is configured to couple to an output pin of the board power supply;

a first voltage division element coupled in series to the first switch to form a first voltage division circuit, wherein the first voltage division circuit is coupled in parallel to the first bias resistor;

a second switch;

a second bias resistor, wherein a first end of the second bias resistor is configured to couple to a ground pin of the board power supply;

a second voltage division element coupled in series to the second switch to form a second voltage division circuit, wherein the second voltage division circuit is coupled in parallel to the second bias resistor,

wherein the first bias resistor is further configured to couple in series to the second bias resistor,

wherein the first voltage division circuit is further configured to couple in series to the second voltage division circuit,

wherein a first coupling point couples the first voltage division circuit and the second voltage division circuit, wherein a second coupling point couples the first bias resistor and the second bias resistor, and wherein the second coupling point is configured to couple the first coupling point to a feedback pin of the board power supply;

a control chip coupled to the first switch and the second switch; and

a detection chip, wherein a first end of the detection chip is coupled to the output pin, wherein a second end of the detection chip is coupled to the control chip, and wherein the detection chip is configured to obtain an initial output voltage of the output pin, and

wherein the control chip is configured to;

control, based on the initial output voltage and a preset voltage, the first switch and the second switch; and

adjust the initial output voltage to a target voltage.

2. The online voltage adjustment circuit of claim 1, wherein the first voltage division element comprises a first voltage division resistor, and wherein the second voltage division element comprises a second voltage division resistor.

3. The online voltage adjustment circuit of claim 2, wherein the control chip is further configured to:

control the first switch to be off and the second switch to be off; and

set the initial output voltage as the target voltage.

4. The online voltage adjustment circuit of claim 2, wherein the control chip is further configured to:

control the first switch to be on and the second switch to be off;

increase the initial output voltage to a first voltage; and

set the first voltage as the target voltage.

5. The online voltage adjustment circuit of claim 2, wherein the control chip is further configured to:

control the first switch to be off and the second switch to be on;

reduce the initial output voltage to a second voltage; and

set the second voltage as the target voltage.

6. The online voltage adjustment circuit of claim 1, wherein the first voltage division element comprises a first digital potentiometer, wherein the second voltage division element comprises a second digital potentiometer, and wherein the control chip is further configured to couple to the first digital potentiometer and the second digital potentiometer.

7. The online voltage adjustment circuit of claim 6, wherein the control chip is further configured to:

control the first switch to be off and the second switch to be off; and

set the initial output voltage as the target voltage.

8. The online voltage adjustment circuit of claim 6, wherein the control chip is further configured to:

control the first switch to be on and the second switch to be off;

increase the initial output voltage to a first voltage; and

set the first voltage as the target voltage.

9. The online voltage adjustment circuit of claim 6, wherein the control chip is further configured to:

control the first switch to be off and the second switch to be on;

reduce the initial output voltage to a second voltage; and

set the second voltage as the target voltage.

10. The online voltage adjustment circuit of claim 8, wherein the control chip is further configured to adjust the first digital potentiometer, and wherein the target voltage is between the initial output voltage and the first voltage.

11. The online voltage adjustment circuit of claim 9, wherein the control chip is further configured to adjust the second digital potentiometer, and wherein the target voltage is between the second voltage and the initial output voltage.

12. The online voltage adjustment circuit of claim 6, wherein the control chip is further configured to:

control the first switch to be on and the second switch to be on; and

adjust the first digital potentiometer and the second digital potentiometer, wherein the target voltage is between a first voltage and a second voltage.

13. The online voltage adjustment circuit of claim 1, wherein the first switch is a first switching transistor, and wherein the second switch is a second switching transistor.

14. The online voltage adjustment circuit of claim 1, wherein the control chip is further configured to obtain the preset voltage.

15. The online voltage adjustment circuit of claim 1, wherein the first switch is a metal-oxide semiconductor field-effect transistor (MOSFET), and wherein the second switch is a switching transistor.

16. The online voltage adjustment circuit of claim 1, wherein the first switch is a switching transistor, and wherein the second switch is a metal-oxide semiconductor field-effect transistor (MOSFET).

17. The online voltage adjustment circuit of claim 1, wherein the first switch is a first metal-oxide semiconductor field-effect transistor (MOSFET), and wherein the second switch is a second MOSFET.

18. The online voltage adjustment circuit of claim 1, wherein the control chip is an advanced reduced instruction set computing (RISC) machines (ARM), a micro control unit (MCU), or a complex programmable logical device (CPLD).

19. The online voltage adjustment circuit of claim 1, wherein the detection chip is coupled to the control chip by an inter-integrated circuit (I2C) or a low pin count (LPC) interface.20. (New) The online voltage adjustment circuit of claim 1, a fixed bias ratio is determined based on resistance values of the first voltage division circuit and the second voltage division circuit.