DRIVE STRENGTH ADJUSTMENT THROUGH VOLTAGE AUTO-SENSE

• US 20120169390A1
• Filed: 02/13/2012
• Published: 07/05/2012
• Est. Priority Date: 02/12/2005
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Barlow, Stephen J., Whitfield, Martin, Ramsdale, Timothy J.
• Granted Patent: US 9,264,529 B2
• Time in Patent Office: Days
• US Class Current: 327/170
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: H04M 1/72409 by interfacing with external accessories hands-free H04M1/60

Abstract

An integrated circuit supports auto-sense of voltage for drive strength adjustment. The method may comprise detecting an input voltage received at an auto-sense pad integrated on a mobile multimedia processing (MMP) chip. The input voltage may be a power supply voltage of the peripheral device received during power-up of the MMP chip, power-up of the peripheral circuitry, and/or dynamically while the MMP is powered-up. The auto-sense pad may adjust drive strength of at least one other pad, which may be an output pad or a bidirectional pad, integrated on the MMP chip may be configured to operate using the determined output voltage. A rise time and/or fall time of signals output by the MMP chip may be varied by the adjustment of the drive strength.

Claims

1. A method for controlling pads of a processor chip, the method comprising:

detecting, on a processor chip, a voltage present at an auto-sense pad integrated with the processor chip; and

adjusting a drive characteristic of a signal pad also integrated with the processor chip, responsive to the voltage detected.

2. The method of claim 1, where adjusting the drive characteristic comprises adjusting voltage applied to the signal pad.

3. The method according to claim 1, wherein the voltage comprises a peripheral device power supply voltage.

4. The method according to claim 1, wherein the signal pad comprises an output pad or a bidirectional pad.

5. The method according to claim 1, wherein adjusting the drive characteristic comprises adjusting signal rise time.

6. The method according to claim 1, wherein adjusting the drive characteristic comprises adjusting current drive.

7. The method according to claim 1, wherein adjusting the drive characteristic comprises adjusting fall time of signals.

8. A processor chip pad control system comprising:

voltage detection circuitry on a processor chip that detects a voltage present at an auto-sense pad integrated on the processor chip; and

drive adjustment circuitry on the processor chip that adjusts a drive characteristic of a signal pad also integrated on the processor chip, responsive to the voltage detected.

9. The system according to claim 8, wherein the voltage comprises a peripheral device power supply voltage.

10. The system according to claim 8, wherein the signal pad comprises an output pad or a bidirectional pad.

11. The system according to claim 8, where the drive characteristic comprises voltage applied to the signal pad.

12. The system according to claim 8, where the drive characteristic comprises rise time.

13. The system according to claim 8, where the drive characteristic comprises adjusting current drive.

14. The system according to claim 8, where the drive characteristic comprises fall time.

20. The system according to claim 8, where the drive characteristic comprises fall time.

15. A product comprising:

a computer program product; and

instructions stored on the computer program that, when executed, causes a system to;

detect a voltage present at an auto-sense pad integrated with a processor chip; and

adjust a drive characteristic of a signal pad also integrated with the processor chip, responsive to the voltage detected.

16. The product of claim 15, wherein the voltage comprises a peripheral device power supply voltage.

17. The product of claim 15, where the drive characteristic comprises voltage applied to the signal pad.

18. The product of claim 15, where the drive characteristic comprises rise time.

19. The product of claim 15, where the drive characteristic comprises adjusting current drive.