Static information storage and retrieval – Read/write circuit – Signals
Reexamination Certificate
2005-06-24
2008-03-11
Phung, Anh (Department: 2824)
Static information storage and retrieval
Read/write circuit
Signals
C326S039000, C365S233500
Reexamination Certificate
active
07342838
ABSTRACT:
Within a programmable logic device (PLD), a DDR SDRAM interface for a DDR SDRAM is provided, the DDR SDRAM providing data to the PLD on the rising and falling edges of a DQS signal, the interface including: a first register adapted to capture data associated with the falling edges of the DQS signal; a second register adapted to capture data associated with the rising edges of the DQS signal; and clock edge selection logic circuitry coupled to clock inputs of the first and second registers and adapted to select between the rising or falling clock edges of an internal PLD clock to clock the first and second registers and thereby transfer the captured data into core logic for the PLD, the selection of the clock edge based on a phase relationship between the internal PLD clock and the DQS signal.
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Agrawal Om P.
Nguyen Bai
Sharpe-Geisler Brad
Tran Giap
Truong Kiet
Hallman Jonathan W.
Lattice Semiconductor Corporation
MacPherson Kwok & Chen & Heid LLP
Phung Anh
Sofocleous Alexander
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