Patent ID: 7957218
Filing Date: 2011-06-07
Classification: G06F

Abstract:
1. In a dual data rate (DDR) memory controller, a method comprising: receiving a first data strobe at a first terminal from a first memory having a first rank; receiving a first data signal at a second terminal from the first memory having the first rank; calibrating the first data signal with the first data strobe to produce a first calibration value; receiving a second data strobe at the first terminal from a second memory having a second rank; receiving a second data signal at the second terminal from the second memory having the second rank; calibrating the second data signal with the second data strobe to produce a second calibration value; determining a final calibration value using the first and second calibration values; and using the final calibration value to time the first data signal and the second data signal during a read operation of the first and second memories.