Patent ID: 9595314
Date: 2017-03-14
CPC Classifications: G06F,G11C

Claim:
1. A method of calibrating communication over a command/address bus of a memory device, comprising: sending a clock signal over a clock signal line; sending a calibration enabling command through command/address terminals at a first rising edge and a first falling edge of the clock signal, wherein the command/address terminals comprise CA sending a first command/address signal through at least some of the command/address terminals with a second rising edge of the clock signal to cause generation of first information, wherein the first command/address signal and the second rising edge of the clock signal have a first phase difference; sending a second command/address signal through the at least some of the command/address terminals with a second falling edge of the clock signal to cause generation of second information, wherein the second command/address signal and the second falling edge of the clock signal have a second phase difference; receiving the first information and the second information through a first set of data terminals and a second set of data terminals respectively; sending a third command/address signal through the at least some of the command/address terminals with a third rising edge of the clock signal to cause generation of third information, wherein the third command/address signal and third rising edge of the clock signal have a third phase difference; sending a fourth command/address signal through the at least some of the command/address terminals with a third falling edge of the clock signal to cause generation of fourth information, wherein the fourth command/address signal and third falling edge of the clock signal have a fourth phase difference; and receiving the third information and the fourth information through the first set of data terminals and the second set of data terminals respectively; wherein the first phase difference and the third phase difference are different from each other, and the second phase difference and the fourth phase difference are different from each other.