70V25L25PFI Datasheet, PDF (16/25 Pages) Integrated Device Technology – True Dual-Ported memory cells which allow simultaneous reads of the same memory location

IDT70V35/34S/L (IDT70V25/24S/L)
High-Speed 3.3V 8/4K x 18 (8/4K x 16) Dual-Port Static RAM
Industrial and Commercial Temperature Ranges
AC Electrical Characteristics Over the Operating
Temperature and Supply Voltage Range for 70V35/34⁽⁶⁾
70V35/34X15
Com'l Ony
70V35/34X20
Com'l
& Ind
70V35/34X25
Com'l Only
Symbol
BUSY TIMING (M/S = VIH)
Parameter
Min. Max. Min. Max. Min. Max. Unit
tBAA
BUSY Access Time from Address Match
____
15
____
20
____
20
ns
tBDA
BUSY Disable Time from Address Not Matched
____
15
____
20
____
20
ns
tBAC
BUSY Access Time from Chip Enable LOW
____
15
____
20
____
20
ns
tBDC
BUSY Dis able Time from Chip Enable HIGH
____
15
____
17
____
17
ns
tAPS
Arbitration Priority Set-up Time⁽²⁾
5
____
5
____
5
____
ns
tBDD
BUSY Disable to Valid Data⁽³⁾
tWH
Write Hold After BUSY⁽⁵⁾
BUSY TIMING (M/S = VIL)
____
18
____
30
____
30
ns
12
____
15
____
17
____
ns
tWB
BUSY Input to Write⁽⁴⁾
tWH
Write Hold After BUSY⁽⁵⁾
0
____
0
____
0
____
ns
12
____
15
____
17
____
ns
PORT-TO-PORT DELAY TIMING
tWDD
Write Pulse to Data Delay⁽¹⁾
____
30
____
45
____
50
ns
tDDD
Write Data Valid to Read Data Delay⁽¹⁾
____
25
____
35
____
35
ns
NOTES:
5624 tbl 13
1. Port-to-port delay through SRAM cells from writing port to reading port, refer to "TIMING WAVEFORM OF WRITE PORT-TO-PORT READ AND
BUSY (M/S = VIH)".
2. To ensure that the earlier of the two ports wins.
3. tBDD is a calculated parameter and is the greater of 0, tWDD – tWP (actual) or tDDD – tDW (actual).
4. To ensure that the write cycle is inhibited during contention.
5. To ensure that a write cycle is completed after contention.
6. 'X' in part number indicates power rating (S or L).
Timing Waveform of Write Port-to-Port Read and BUSY^(2,4,5) (M/S = VIH)
tWC
ADDR"A"
R/W"A"
DATAIN "A"
tAPS⁽¹⁾
MATCH
tWP
tDW
tDH
VALID
ADDR"B"
BUSY"B"
tBAA
MATCH
tBDA
tBDD
tWDD
DATAOUT "B"
NOTES:
tDDD ⁽³⁾
1. To ensure that the earlier of the two ports wins. tAPS is ignored for M/S = VIL (slave).
2. CEL = CER = VIL.
3. OE = VIL for the reading port.
4. If M/S = VIL (slave), BUSY is an input. Then for this example BUSY“A” = VIH and BUSY“B” input is shown above.
5. All timing is the same for both left and right ports. Port “A” may be either the left or right port. Port “B ” is the port opposite from port “A”.
VALID
5624 drw 13
6.1462