CY7C4425-35AI Ver la hoja de datos (PDF) - Cypress Semiconductor

Número de pieza

componentes Descripción

Lista de partido

CY7C4425-35AI

64, 256, 512, 1K, 2K, 4K x 18 Synchronous FIFOs

Cypress Semiconductor 

CY7C4425/4205/4215

CY7C4225/4235/4245

Switching Waveforms (continued)

Programmable Almost Full Flag Timing

WCLK

tCLKH

WEN

PAF [24]

RCLK

REN

Note 23

tCLKL

tENS tENH

tPAF

FULL − M WORDS

IN FIFO [25]

FULL − M + 1 WORDS

IN FIFO [26]

tPAF

tENS

42X5–15

Programmable Almost Full Flag Timing (applies only in SMODE (SMODE in LOW))

WCLK

tCLKH

tCLKL

Note

27

WEN

tENS tENH

WEN2

PAF

RCLK

REN

tENS tENH

FULL- M+1Ω ORDS

INFIFO

Note

28

tPAF

FULL − M WORDS

IN FIFO[29]

tSKEW3[30]

tENS

tENS tENH

tPAFsynch

42X5–16

Notes:

23. PAF offset = m. Number of data words written into FIFO already = 64 – m + 1 for the CY7C4425, 256 – m + 1 for the CY7C4205, 512 – m + 1 for the

CY7C4215. 1024 – m + 1 for the CY7C4225, 2048 – m + 1 for the CY7C4235, and 4096 – m + 1 for the CY7C4245.

24. PAF is offset = m.

25. 64 – m words in CY7C4425, 256 – m words inCY7C4205, 512 – m word in CY7C4215. 1024 – m words in CY7C4225, 2048 – m words in CY7C4235, and

4096 – m words in CY7C4245.

26. 64 – m + 1 words in CY7C4425, 256 – m + 1 words in CY7C4205, 512 – m +1 words in CY7C4215, 1024 – m + 1 CY7C4225, 2048 – m + 1 in CY74235,

and 4096 – m + 1 words in CY7C4245.

27. If a write is performed on this rising edge of the write clock, there will be Full – (m – 1) words of the FIFO when PAF goes LOW.

28. PAF offset = m.

29. 64 – m words in CY7C4425, 256 – m words in FIFO for CY7C4205, 512 – m word in CY7C4215. 1024 – m words in CY7C4225, 2048 – m words in CY7C4235,

and 4096 – m words in CY7C4245.

30. tSKEW3 is the minimum time between a rising RCLK and a rising WCLK edge for PAF to change state during that clock cycle. If the time between the edge of RCLK and the

rising edge of WCLK is less than tSKEW3, then PAF may not change state until the next WCLK rising edge.

11

Share Link: