Non-linear common coarse delay system and method for delaying data strobe

Abstract

A non-linear common coarse delay system and method for delaying a data strobe in order to preserve fine delay accuracy and compensate PVT (Process, Voltage, and Temperature) variation effects. A common coarse delay and a fine delay can be initialized to a quarter-cycle delay for shifting a read output DQS (Data Queue Strobe) associated with a memory device in order to sample a read output DQ (Data Queue) within a physical layer. The fine delay can be programmed from minimum to maximum delay with fixed linear increments at each delay step in order to determine the resolution and accuracy of the delay. An optimum delay size of both the coarse and the fine delay can be determined based on an application slowest frequency of operation. A spare coarse delay and a functional coarse delay can be trained in association with a spare fine delay and the functional fine delay can be updated in order to monitor the process, voltage, and temperature variation effects.