QUASI-CONTINUOUS VOLTAGE REGULATOR AND CONTROLLER

• US 20100320987A1
• Filed: 06/22/2009
• Published: 12/23/2010
• Est. Priority Date: 06/22/2009
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Tran, Tuan Van, Boling, Brian Dean
• Granted Patent: US 8,232,788 B2
• Time in Patent Office: Days
• US Class Current: 323/284
• CPC Class Codes: G11B 5/09 Digital recording
• CPC Class Codes: H02M 3/1563 without using an external clock H02M3/158 takes precedence
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load

Abstract

A controller for a voltage regulator includes a hysteretic circuit that generates a hysteretic voltage output as a function of a regulated voltage and that generates a hysteretic current output as a function of an inductor current. A switch control circuit provides a quasi-continuous control output as a function of the hysteretic current output from a start time when the regulated voltage rises above a higher hysteretic voltage until a stop time when the regulated voltage falls below a lower hysteretic voltage.

Claims

1. A controller, comprising:

a hysteretic circuit that generates a hysteretic voltage output as a function of a regulated voltage and that generates a hysteretic current output as a function of an inductor current; and

a switch control circuit that provides a quasi-continuous control output as a function of the hysteretic current output from a start time when the regulated voltage rises above a higher hysteretic voltage until a stop time when the regulated voltage falls below a lower hysteretic voltage.

2. The controller of claim 1 wherein the hysteretic circuit comprises a voltage threshold coupled to a hysteretic voltage comparator.

3. The controller of claim 1 wherein the hysteretic circuit comprises a current threshold coupled to a hysteretic current comparator.

4. The controller of claim 1 wherein the switch control circuit comprises a latch that asynchronously controls the quasi-continuous control output.

5. The controller of claim 1 wherein the hysteretic circuit comprises a synchronous gate driver that synchronizes the quasi-continuous control output with a rectifier element control output.

6. The controller of claim 1 further comprising at least one current sensor input pin coupled to the hysteretic circuit.

7. The controller of claim 1 further comprising a ramp generator coupled to the hysteretic circuit.

8. A voltage regulator, comprising:

an output circuit that comprises an inductor and a switch that couples a first polarity supply voltage to the inductor to produce an inductor current; and

the output circuit provides an opposite polarity regulated voltage;

a hysteretic circuit that generates a hysteretic voltage output as a function of the regulated voltage and that generates a hysteretic current output as a function of the inductor current; and

a switch control circuit that provides a quasi-continuous control output to the switch as a function of the hysteretic current output from a start time when the regulated voltage rises above a higher hysteretic voltage until a stop time when the regulated voltage falls below a lower hysteretic voltage.

9. The voltage regulator of claim 8 wherein the quasi-continuous control output shuts off the switch when the regulated voltage falls below the lower hysteretic voltage.

10. The voltage regulator of claim 8 wherein the output circuit comprises a capacitor and a rectifier element that rectifies current that flows between the inductor and the capacitor.

11. The voltage regulator of claim 10 wherein the rectifier element comprises a Schottky diode.

12. The voltage regulator of claim 10 wherein the rectifier element comprises a field effect transistor.

13. The voltage regulator of claim 10 wherein the output circuit comprises a capacitor coupled to the rectifier element.

14. The voltage regulator of claim 8 wherein the inductor comprises a single two-terminal inductor.

15. The voltage regulator of claim 8 wherein the inductor comprises a soft magnetic core.

16. A method of a voltage regulation, comprising:

coupling a first polarity supply voltage to an inductor through a switch to produce an inductor current;

generating an opposite polarity regulated voltage from the inductor current;

generating a hysteretic voltage output as a function of the regulated voltage and generating a hysteretic current output as a function of the inductor current; and

providing a quasi-continuous control output to the switch as a function of the hysteretic current output from a start time when the regulated voltage rises above a higher hysteretic voltage until a stop time when the regulated voltage falls below a lower hysteretic voltage.

17. The method of claim 16, comprising:

shutting off the switch when the regulated voltage falls below the lower hysteretic voltage.

18. The method of claim 16, comprising:

rectifying a current flowing from the inductor to a capacitor.

19. The method of claim 16, comprising:

asynchronously controlling the quasi-continuous control output.

20. The method of claim 16, comprising:

synchronously controlling the quasi-continuous control output.