Load driver

• US 9,923,559 B2
• Filed: 08/19/2015
• Issued: 03/20/2018
• Est. Priority Date: 04/18/2007
• Status: Active Grant

• Current Assignee: Monterey Research, LLC (Vector Capital Corporation)
• Original Assignee: Monterey Research, LLC (Vector Capital Corporation)
• Inventors: Wright, David G., Muriby, Jason Faris, Hancioglu, Erhan
• Primary Examiner(s): NGUYEN, LONG T
• Application Number:
  US14/829,938
• Publication Number:
  US 20160006434A1
• Time in Patent Office: 944 Days
• Field of Search: None
• CPC Class Codes: H03K 17/687 the devices being field-effect transistors
• CPC Class Codes: H03K 19/0016 by using a control or a clock signal, e.g. in order to apply power supply
• CPC Class Codes: H03K 19/00369 Modifications for compensating variations of temperature, supply voltage or other physical parameters

Abstract

A method for driving a load includes driving a load to an initial voltage within a voltage window, the voltage window based on an input voltage and an offset voltage, and driving the load to approximately the input voltage.

Claims

1. A device, comprising:

a first circuit configured to drive an output terminal to a first voltage; and

a second circuit configured to adjust the first voltage at the output terminal to a second voltage,

wherein the first circuit and the second circuit are configured to be operational alternatively, wherein the output terminal is configured to drive a liquid crystal display panel, and wherein the first and second circuits are configured to be turned off when the second voltage reaches a steady state.

2. The device of claim 1, further comprising:

a voltage generator configured to generate an input voltage, wherein the first voltage is configured to be within a voltage range that is based on the input voltage and an offset voltage, wherein the voltage range is defined by an upper voltage and a lower voltage.

3. The device of claim 2, wherein the second voltage is configured to approximate the input voltage.

4. The device of claim 1, wherein the output terminal includes a non-resistive load.

5. The device of claim 2, wherein the offset voltage is one of programmable or predetermined.

6. The device of claim 2, wherein the first circuit comprises:

a first comparator configured to control a first switch according to at least an outcome of comparing the first voltage to the lower voltage;

a second comparator configured to control a second switch according to at least an outcome of comparing the first voltage to the upper voltage;

a first current source configured to charge the output terminal when the first switch is turned on; and

a second current source configured to discharge the output terminal when the second switch is turned on.

7. The device of claim 6, wherein the first comparator and the second comparator are configured to turn off the first switch and the second switch respectively when the first voltage is within the voltage range.

8. The device of claim 4, wherein the non-resistive load includes at least one of a capacitive load, an inductive load, or a combination thereof.

9. The device of claim 1, further comprising:

a control circuit configured to control operation parameters of the first circuit and the second circuit including at least a timing and a sequence of operating the first circuit and the second circuit.

10. A method comprising:

driving a load, by a first circuit, to a first voltage within a voltage window, the voltage window based on at least an input voltage and an offset voltage;

adjusting, by a second circuit, the first voltage to a second voltage, the second voltage approximates the input voltage;

configuring the driving the load to the first voltage and the adjusting the first voltage to the second voltage to operate alternatively, wherein the second voltage is configured to drive a liquid crystal display panel; and

turning off the first and second circuits when the second voltage driving the liquid crystal display panel reaches a steady state.

11. The method of claim 10, wherein the first voltage is non-zero.

12. The method of claim 10, further comprising:

utilizing a plurality of control signals to maintain the second voltage at a substantially constant level.

13. The method of claim 10, further comprising:

configuring the voltage window to be defined by an upper voltage and a lower voltage.

14. The method claim 13, wherein the upper voltage is substantially a sum of the input voltage and the offset voltage, wherein the lower voltage is substantially a difference between the input voltage and the offset voltage.

15. The method of claim 10, further comprising:

initiating the adjusting the first voltage to the second voltage when the first voltage falls within the voltage window.

16. The method of claim 10, further comprising:

driving rail-to-rail voltages associated with the load.

17. A load driver, comprising:

a voltage generator configured to provide an input voltage;

a high drive circuit configured to drive a load to a first voltage, wherein the first voltage falls substantially within a voltage range based on at least the input voltage;

a low drive circuit configured to adjust the first voltage to a second voltage to substantially reach the input voltage; and

a control circuit configured to alternate operations of the high drive circuit and the low drive circuit,

wherein the load driver is configured to drive a liquid crystal display panel, and wherein the high drive and low drive circuits are configured to be turned off when the second voltage reaches a steady state.

18. The load drive of claim 17, wherein the load is non-resistive.

19. The load driver of claim 17, wherein the high drive circuit comprises at least a first comparator, a second comparator, a first switch, a second switch, a first current source to charge the load, and a second current source to discharge the load.

20. The load driver of claim 17, wherein the voltage range is further based on at least an offset voltage.