Browse Prior Art Database

Power Savings Mode for Serial Links

IP.com Disclosure Number: IPCOM000110727D
Original Publication Date: 1992-Dec-01
Included in the Prior Art Database: 2005-Mar-25
Document File: 1 page(s) / 44K

Publishing Venue

IBM

Related People

Floryance, GG: AUTHOR

Abstract

A method for reducing the power consumption of serial interface logic is disclosed. High-speed receiver logic enters a powerdown mode of operation in the absence of a received signal. The serial interface receiver continues to monitor the signal and the serial interface logic exits the power-down state when the receiver detects a signal.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 92% of the total text.

Power Savings Mode for Serial Links

      A method for reducing the power consumption of serial interface
logic is disclosed.  High-speed receiver logic enters a powerdown
mode of operation in the absence of a received signal.  The serial
interface receiver continues to monitor the signal and the serial
interface logic exits the power-down state when the receiver detects
a signal.

      In order to reduce the power consumption of the interface
electronics, a SIGNAL DETECT line is implemented within the serial
interface receiver.  The SIGNAL DETECT line shall indicate whether
their is or is not a signal present at the input to the receiver.
This may be determined either by detecting a high frequency signal
(at the serial data rate) or by some other means such as detecting a
specific current or voltage level.

      A device will enter power-down mode either as a result of a
message received over the interface or by the absence of a received
signal (as determined by the SIGNAL DETECT line) for some specified
period of time.  Normally, in the power-down state, the bulk of the
device electronics will be powered down.  In addition, the receiver
interface circuitry will also be powered down which includes high
frequency clock recovery circuitry.  While in the power-down mode,
the SIGNAL DETECT line will continue to monitor the received signal.
When a received signal is detected, the interface logic will exit the
power-down state and power-up the sleeping interf...