CY7C4201 CYPRESS [Cypress Semiconductor], CY7C4201 Datasheet - Page 12

• Manufacturer Part Number: CY7C4201
• Description: 64/256/512/1K/2K/4K/8K x 9 Synchronous FIFOs
• Manufacturer: CYPRESS [Cypress Semiconductor]

Document #: 38-06016 Rev. *A
Switching Waveforms
Notes:
Programmable Almost Full Flag Timing
Write Programmable Registers
21. t
22. PAE offset = n.
23. If a Read is performed on this rising edge of the Read clock, there will be Empty + (n – 1) words in the FIFO when PAE goes LOW.
24. 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.
25. PAF offset = m.
26. 64-m words for CY7C4421, 256 – m words in FIFO for CY7C4201, 512 – m words for CY7C4211, 1024 – m words for CY7C4221, 2048 – m words for CY7C4231,
27. t
(if applicable)
WEN2/LD
WEN2
WCLK and the rising RCLK is less than t
4096 – m words for CY7C4241, 8192 – m words for CY7C4251.
edge of RCLK and the rising edge of WCLK is less than t
SKEW2
SKEW2
WEN1
WCLK
WCLK
D
WEN1
REN1,
RCLK
REN2
0
PAF
–D
is the minimum time between a rising WCLK and a rising RCLK edge for PAE to change state during that clock cycle. If the time between the edge of
is the minimum time between a rising RCLK edge and a rising WCLK edge for PAF to change during that clock cycle. If the time between the rising
8
t
t
CLKH
CLKH
FULL
(continued)
t
CLK
t
t
ENS
ENS
t
IN FIFO
DS
SKEW2
M+1 WORDS
PAE OFFSET
t
t
ENS
ENS
, then PAE may not change state until the next RCLK.
LSB
t
t
ENH
ENH
t
t
CLKL
CLKL
SKEW2
t
ENH
t
DH
, then PAF may not change state until the next WCLK.
Note
PAE OFFSET
25
Note
24
MSB
t
PAF
t
ENS
PAF OFFSET
t
SKEW2
FULL
CY7C4421/4201/4211/4221
LSB
IN FIFO
t
[27]
ENS
M WORDS
CY7C4231/4241/4251
t
[26]
ENH
PAF OFFSET
MSB
t
PAF
Page 12 of 18