High speed signaling system with adaptive transmit pre-emphasis

摘要

A high-speed signaling system with adaptive transmit pre-emphasis. A transmit circuit has a plurality of output drivers to output a first signal onto a signal path. A receive circuit is coupled to receive the first signal via the signal path and configured to generate an indication of whether the first signal exceeds a threshold level. A first threshold control circuit is coupled to receive the indication from the receive circuit and configured to adjust the threshold level according to whether the first signal exceeds the threshold level. A drive strength control circuit is coupled to receive the indication from the receive circuit and configured to adjust a drive strength of at least one output driver of the plurality of output drivers according to whether the first signal exceeds the threshold level.

主权项

1. An integrated circuit, comprising:
a transmitter to transmit bits of a digital sequence onto a conductive path external to the integrated circuit to a receiver, using a signal level that is a logical function of binary state of a current bit to be transmitted and binary state of another bit of the digital sequence, the transmitter characterized by a peak power constraint; circuitry to receive a request from the receiver to change a tap weight used to generate the signal level, and to change the tap weight responsive to the request; and circuitry to set the tap weight in a manner responsive to the request so as to maintain operation of the transmitter within the peak power constraint.