Apparatus and method for dynamically aligned source synchronous receiver

Abstract

A method is provided that compensates for misalignment on a synchronous data bus. The method includes: replicating propagation path lengths, loads, and buffering of a radial distribution network for a strobe; receiving a first signal, and generating a second signal by employing the replicated propagation path lengths, loads, and buffering; when an update signal is asserted, when an update signal is asserted, measuring a propagation time beginning with assertion of the first signal and ending with assertion of the second signal by selecting one of a plurality of successively delayed versions of the first signal that coincides with the assertion of the second signal, wherein said selecting comprises incrementing and decrementing bus states of select inputs on a mux, wherein the plurality of successively delayed versions of the first signal comprises inputs to the mux; gray encoding a value on a lag bus that indicates the propagation time; and receiving one of a plurality of radially distributed strobes and a data bit, and delaying registering of the data bit by the propagation time. The receiving includes generating successively delayed versions of the data bit; receiving the value on the lag bus, and selecting one of the successively delayed versions of the data bit that corresponds to the value; and registering the state of the one of the successively delayed versions of the data bit upon assertion of one of a plurality of radially distributed strobe signals.