Implementing voltage sense point switching for regulators

• US 10,110,116 B1
• Filed: 06/13/2017
• Issued: 10/23/2018
• Est. Priority Date: 06/13/2017
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Berge, Layne A., Egan, Patrick K.
• Primary Examiner(s): Tran, Nguyen
• Assistant Examiner(s): Lee, Jye-June
• Application Number:
  US15/621,560
• Time in Patent Office: 497 Days
• CPC Class Codes: H02M 1/0054 Transistor switching losses periodically suspending operation of switching converter in low power mode H02M1/0035
• CPC Class Codes: H02M 1/32 Means for protecting converters other than automatic disconnection
• CPC Class Codes: H03K 17/0822 in field-effect transistor switches
• CPC Class Codes: H03K 17/165 by feedback from the output circuit to the control circuit
• CPC Class Codes: H03K 2217/0027 Measuring means of, e.g. currents through or voltages across the switch
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A method and circuit are provided for implementing voltage sense point switching for regulators. A regulator voltage sensing circuit includes at least two sense points enabling a regulator to compensate for voltage drop at the sense points and providing at least one of the sense points at a location to be switched. Switched loads have gains at the sense points to compensate for the voltage drop in a transistor switch at maximum load. A non-switched output is sensed and functions as an over-voltage protection to limit the transistor switch voltage drop.

Claims

1. A method for implementing voltage sense point switching for regulators comprising:

enabling a regulator to compensate for voltage drop at least two sense points;

providing at least one of said sense points at a location to be switched;

providing switched loads having gains at said sense point to compensate for voltage drop in a transistor switch at maximum load;

sensing said non-switched output for providing over-voltage protection to limit voltage drop of said transistor switch;

providing an analog switching network including a respective diode function for multiple voltage sense points, and implementing said respective diode function using a respective operational amplifier and a respective diode connected to an output of said respective operational amplifier.

2. The method as recited in claim 1, includes providing said transistor switch with a field effect transistor (FET) switch.

3. The method as recited in claim 2, includes providing an N-channel field effect transistor (NFET) switch.

4. The method as recited in claim 2, includes said switched sense point location connected to said FET switch.

5. The method as recited in claim 1, includes providing two sense points and providing inputs from said two sense points to each said respective operational amplifier.

6. The method as recited in claim 1, includes providing 0 volts loss across said respective diode using compensation with said respective operational amplifier.

7. The method as recited in claim 1, includes providing biasing and feedback resistors with said respective operational amplifier to compensate for loss across said transistor switch and to avoid an over-voltage condition.

8. The method as recited in claim 1, includes turning off said transistor switch and only sensing said non-switched sense point.

9. The method as recited in claim 8, includes only allowing said switched sense point to be sensed until said transistor switch is turned back on and its voltage exceeds a threshold value.

10. A circuit for implementing voltage sense point switching for regulators comprising:

at least two sense points enabling a regulator to compensate for voltage drop at the sense points;

at least one of the sense points provided at a location to be switched;

switched loads having gains at the sense points to make up for the voltage drop in a transistor switch at maximum load; and

a non-switched sense point functions as an over-voltage protection to limit the transistor switch voltage drop; and

an analog switching network for each of said multiple voltage sense points, each said analog switching function includes a respective diode function, and said respective diode function implemented using a respective operational amplifier and a respective diode connected to an output of said respective operational amplifier.

11. The circuit as recited in claim 10, wherein said transistor switch includes a field effect transistor (FET) switch.

12. The circuit as recited in claim 10, wherein said transistor switch includes an N-channel field effect transistor (NFET) switch.

13. The circuit as recited in claim 11, wherein said switched sense point location is connected to said FET switch.

14. The circuit as recited in claim 10, wherein said respective operational amplifier includes biasing and feedback resistors to compensate for loss across said transistor switch and to avoid an over-voltage condition.

15. The circuit as recited in claim 10, includes two sense points and inputs from said two sense points are applied to each said respective operational amplifier.

16. The circuit as recited in claim 10, includes only sensing said non-switched sense point responsive to turning off said transistor switch.

17. The circuit as recited in claim 15, includes only sensing said switched sense point until said transistor switch is turned back on and its voltage exceeds a threshold value.