IDT70V261S/L
High-Speed 16K x 16 Dual-Port Static RAM with Interrupt
Industrial and Commercial Temperature Ranges
Waveform of Read Cycles(5)
tRC
ADDR
(4)
t
t
AA
(4)
ACE
CE
OE
(4)
t
AOE
(4)
t
ABE
UB, LB
R/W
(1)
tOH
tLZ
VALID DATA(4)
DATAOUT
BUSYOUT
(2)
tHZ
(3,4)
3040 drw 0
tBDD
NOTES:
1. Timing depends on which signal is asserted last, OE, CE, LB, or UB.
2. Timing depends on which signal is de-asserted first CE, OE, LB, or UB.
3. tBDD delay is required only in cases where the opposite port is completing a write operation to the same address location. For simultaneous read operations BUSY has no
relation to valid output data.
4. Start of valid data depends on which timing becomes effective last tAOE, tACE, tAA or tBDD.
5. SEM = VIH.
AC Electrical Characteristics Over the
OperatingTemperatureandSupplyVoltage(5)
70V261X25
70V261X35
Com'l Only
70V261X55
Com'l Only
Com'l
& Ind
Symbol
Parameter
Min.
Max.
Min.
Max.
Min.
Max.
Unit
WRI TE CYCLE
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
____
t
WC
EW
AW
AS
WP
WR
DW
HZ
DH
WZ
OW
SWRD
SPS
Write Cycle Time
25
20
20
0
35
30
30
0
55
45
45
0
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
t
Chip Enable to End-of-Write(3)
Address Valid to End-of-Write
Address Set-up Time(3)
Write Pulse Width
t
t
t
20
0
25
0
40
0
t
Write Recovery Time
Data Valid to End-of-Write
Output High-Z Time(1,2)
Data Hold Time(4)
t
15
20
30
____
____
____
t
15
20
25
____
____
____
t
0
0
0
Write Enable to Output in High-Z(1,2)
Output Active from End-of-Write(1, 2,4)
SEM Flag Write to Read Time
SEM Flag Contention Window
15
20
25
____
____
____
t
____
____
____
t
0
5
5
0
5
5
0
5
5
____
____
____
____
____
____
t
t
ns
3040 tbl 12
NOTES:
1. Transition is measured 0mV from Low- or High-impedance voltage with Output Test Load (Figure 2).
2. This parameter is guaranteed by device characterization, but is not production tested.
3. To access RAM, CE = VIL and SEM = VIH. To access semaphore, CE = VIH and SEM = VIL. Either condition must be valid for the entire tEW time.
4. The specification for tDH must be met by the device supplying write data to the RAM under all operating conditions. Although tDH and tOW values will vary over voltage and
temperature, the actual tDH will always be smaller than the actual tOW.
5. 'X' in part number indicates power rating (S or L).
7
6.42