Memory controller using a data strobe signal and method of calibrating data strobe signal in a memory controller

Patent metadata

Field	Value
Publication number	US-9105327-B2
Application number	US-201313861641-A
Country	US
Kind code	B2
Filing date	Apr 12, 2013
Priority date	Apr 12, 2013
Publication date	Aug 11, 2015
Grant date	Aug 11, 2015

Abstract

A memory controller and a method of calibrating the memory controller are provided. Input circuitry in the memory controller receives a differential pair of data strobe signals from a memory and generates a logical data strobe signal in dependence on a voltage difference between the differential pair of data strobe signals. Hysteresis circuitry, when active, increases by a predetermined offset a threshold voltage difference at which the input circuitry changes a logical state of the logical data strobe signal. Gate signal generation circuitry generates a data strobe gating signal, wherein the memory controller interprets the logical data strobe signal as valid when the data strobe gating signal is asserted. The memory controller performs a training process to determine a timing offset for the data strobe gating signal with respect to said logical data strobe signal, wherein the training process provides a first phase in which the hysteresis circuitry is active and a second phase in which the hysteresis circuitry is inactive.

First claim

We claim:

1. A memory controller comprising:
input circuitry configured to receive a differential pair of data strobe signals from a memory, said input circuitry configured to generate a logical data strobe signal in dependence on a voltage difference between said differential pair of data strobe signals;
hysteresis circuitry configured, when switched to an active state, to increase by a predetermined offset a threshold voltage difference at which said input circuitry is configu…

Assignees

• Advanced Risc Mach Ltd

Inventors

• Prakash Gyan
• Dey Ranabir
• Kumar Nidhir

Classifications

• G06F13/1689 Primary

  Physics · mapped topic

• G11C7/222 Primary

  Physics · mapped topic

• G11C7/04

  Physics · mapped topic