FLEXcertifydll
Full Member level 4

Working with DDRs in PrimeTime
Andrew Cheng
Cisco Systems
170 West Tasman Dr.
San Jose, CA 95134
ABSTRACT
The timing of I/O interfaces can present some challenges for users of STA tools. This paper will
discuss using PrimeTime to tackle one of today's common I/O timing problems – the Double
Data Rate (DDR) interface.
Building on the techniques for source-synchronous interfaces covered in last year's "Complex
Clocking Situations" paper [1], the authors will demonstrate how to correctly analyze and
constrain several different implementations of the DDR interface. In the process, the authors will
demonstrate a number of generally useful PrimeTime techniques with application beyond DDRs.
Andrew Cheng
Cisco Systems
170 West Tasman Dr.
San Jose, CA 95134
ABSTRACT
The timing of I/O interfaces can present some challenges for users of STA tools. This paper will
discuss using PrimeTime to tackle one of today's common I/O timing problems – the Double
Data Rate (DDR) interface.
Building on the techniques for source-synchronous interfaces covered in last year's "Complex
Clocking Situations" paper [1], the authors will demonstrate how to correctly analyze and
constrain several different implementations of the DDR interface. In the process, the authors will
demonstrate a number of generally useful PrimeTime techniques with application beyond DDRs.