35
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
IDT72V3640/50/60/70/80/90 3.3V HIGH DENSITY SUPERSYNC IITM 36-BIT FIFO
1,024 x 36, 2,048 x 36, 4,096 x 36, 8,192 x 36, 16,384 x 36 and 32,768 x 36
OCTOBER 22, 2008
NOTES:
1. n =
PAE offset.
2. For IDT Standard mode
3. For FWFT mode.
4. tSKEW2 is the minimum time between a rising WCLK edge and a rising RCLK edge to guarantee that
PAE will go HIGH (after one RCLK cycle plus tPAES). If the time between the rising edge of
WCLK and the rising edge of RCLK is less than tSKEW2, then the
PAE deassertion may be delayed one extra RCLK cycle.
5.
PAE is asserted and updated on the rising edge of WCLK only.
6. Select this mode by setting PFM HIGH during Master Reset.
Figure 19. Synchronous Programmable Almost-Empty Flag Timing (IDT Standard and FWFT Modes)
NOTES:
1. m =
PAF offset.
2. D = maximum FIFO Depth.
In IDT Standard Mode: D = 1,024 for the IDT72V3640, 2,048 for the IDT72V3650, 4,096 for the IDT72V3660, 8,192 for the IDT72V3670, 16,384 for the IDT72V3680 and 32,768
for the IDT72V3690.
In FWFT Mode: D = 1,025 for the IDT72V3640, 2,049 for the IDT72V3650, 4,097 for the IDT72V3660, 8,193 for the IDT72V3670, 16,385 for the IDT72V3680 and 32,769 for the
IDT72V3690.
3.
PAF is asserted to LOW on WCLK transition and reset to HIGH on RCLK transition.
4. Select this mode by setting PFM LOW during Master Reset.
Figure 20. Asynchronous Programmable Almost-Full Flag Timing (IDT Standard and FWFT Modes)
WCLK
tCLKH
tCLKL
tENS
tENH
WEN
PAF
tENS
tPAFA
D - (m + 1) words
in FIFO
RCLK
tPAFA
REN
4667 drw25
D - m words
in FIFO
D - (m + 1) words in FIFO
WCLK
tENH
tCLKH
tCLKL
WEN
PAE
RCLK
tENS
n words in FIFO (2),
n+1 words in FIFO (3)
tPAES
tSKEW2
tPAES
12
(4)
REN
4667 drw24
tENS
tENH
n+1 words in FIFO (2),
n+2 words in FIFO (3)
n words in FIFO (2),
n+1 words in FIFO (3)