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. A circuit board comprising:
at least one signal trace to connect to a signal path; an integrated circuit including a multi-tap transmitter, the multi-tap transmitter operable to output a digital sequence onto the signal path via the at least one signal trace in accordance with a set of tap weights; and the multi-tap transmitter operable to update the set of tap weights responsive to an indication from a receiver, the indication generated responsive to a power constraint of the multi-tap transmitter.