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COMMERCIALTEMPERATURERANGE
IDT72V3653/72V3663/72V3673 3.3V CMOS SyncFIFOTM WITH
BUS-MATCHING 2,048 x 36, 4,096 x 36, and 8,192 x 36
Figure 21. Block Diagram of 256 x 36, 512 x 36, 1,024 x 36 Synchronous FIFO Memory with
Programmable Flags used in Depth Expansion Configuration
NOTES:
1. Mailbox feature is not supported in depth expansion applications. (MBA + MBB tie to GND)
2. Transfer clock should be set either to the Write Port Clock (CLKA) or the Read Port Clock (CLKB), whichever is faster.
3. The amount of time it takes for
EF/OR of the last FIFO in the chain to go HIGH (i.e. valid data to appear on the last FIFO’s outputs) after a word has been written to the first FIFO is the
sum of the delays for each individual FIFO: (N - 1)*(4*transfer clock) + 3*TRCLK, where N is the number of FIFOs in the expansion and TRCLK is the CLKB period.
4. The amount of time it takes for
FF/IR of the first FIFO in the chain to go HIGH after a word has been read from the last FIFO is the sum of the delays for each individual FIFO:
(N - 1)*(3*transfer clock) + 2*TWCLK, where N is the number of FIFOs in the expansion and TWCLK is the CLKA period.
DATA IN (Dn)
READ CLOCK (CLKB)
READ ENABLE (ENB)
EMPTY FLAG/
OUTPUT READY (EF/OR)
CHIP SELECT (CSB)
DATA OUT (Qn)
TRANSFER CLOCK
4662 drw23
IDT
72V3653
72V3663
72V3673
VCC
IDT
72V3653
72V3663
72V3673
WRITE
READ
A0-A35
MBA
CHIP SELECT (CSA)
WRITE SELECT (W/RA)
WRITE ENABLE (ENA)
ALMOST-FULL FLAG (AF)
FULL FLAG/
INPUT READY (FF/IR)
WRITE CLOCK (CLKA)
CLKB
EF/OR
ENB
CSB
B0-B35
W/RB
MBB
CLKA
ENA
FF/IR
CSA
MBA
A0-A35
W/RA
READ SELECT (W/RB)
ALMOST-EMPTY FLAG (AE)
B0-B35
MBB
VCC
n
Qn
Dn
VCC