Data and data strobe circuits and operating protocol for double data rate memories

• Main Authors: Rogers, Jim L, Fiscus, Timothy E
• Format: Patent
• Language: English
• Published: 04.03.2003

This invention relates generally to computers and more particularly to a computer main memory that uses a data strobe protocol to transfer data between the computer's main memory and controller. This is a circuit and protocol for relaxing the strobe to data relationship to permit the writing into and reading out of a double data rate DRAM array at data transfer rates higher than any known circuits that utilize a strobe and data protocol. This result is accomplished by modifying the prior art write circuitry by adding a strobe generator coupled to both the data input and the strobe input to control the write circuit multi-latch and by modifying the prior art read circuit by coupling the initial and enable circuit to the data drivers and adding a data compare circuit that is coupled between the memory storage array and the strobe toggle to control the strobe. In this way the present invention relaxes the use of the strobe to data relationships for reads and writes except when there are no data transitions and ends the necessity of aligning the strobe with the data eye. By so eliminating the need for strobe to data eye alignment the present invention can use smaller data eyes and data transfer rates higher than those that can be utilized by the prior art circuits.