STK12C68-M Simtek, STK12C68-M Datasheet - Page 5

• Manufacturer Part Number: STK12C68-M
• Description: CMOS NV SRAM 8K X 8 AUTOSTORE NONVOLATILE STATIC RAM
• Manufacturer: Simtek

MODE SELECTION
Note k: The six consecutive addresses must be in order listed - (0000, 1555, 0AAA, 1FFF, 10F0, 0F0F) for a STORE cycle or (0000, 1555, 0AAA, 1FFF, 10F0,
Note l:
Note m: HSB initiated STORE operation actually occurs only if a WRITE has been done since last STORE operation. After the STORE (if any) completes, the
HARDWARE STORE / RECALL
Note e:
Note n:
Note o:
HARDWARE STORE / RECALL
RECALL
STORE
NO.
V
22
23
24
25
26
SRAM
SWITCH
Inhibit
V
HSB
H
X
CAP
E
L
L
L
L
W
I/O state assumes that G
0F0E) for a RECALL cycle . W must be high during all six consecutive cycles. See STORE cycle and RECALL cycle tables and diagrams for further details.
part will go into standby mode inhibiting all operation until HSB rises.
These parameters guaranteed but not tested.
HSB is an I/O that has a weak internal pullup; it is basically an open drain output. It is meant to allow up to 32 STK12C68-Ms to be ganged together for
simultaneous storing. Do not use HSB to pullup any external circuitry other than other STK12C68-M HSB pins.
A RECALL cycle is initiated automatically at power up when V
t
t
t
t
t
V
I
I
RECALL
STORE
DELAY
RECOVER
ASSERT
HSB_OL
HSB_OH
SWITCH
Power Up RECALL
SYMBOLS
W
H
H
H
X
L
X
t
t
t
t
HLHH
HLQZ
HHQX
HLHX
HSB
Brown Out RECALL
H
H
H
H
H
L
NONVOLATILE MEMORY OPERATION
V
RECALL Cycle Duration
STORE Cycle Duration
HSB Low to Inhibit On
HSB High to Inhibit Off
External STORE Pulse Width
Low Voltage Trigger Level
HSB Output Low Current
HSB Output High Current
IL
. Activation of nonvolatile cycles does not depend on the state of G.
PARAMETER
A
12
0AAA
1FFF
0AAA
1FFF
0F0E
10F0
0F0F
10F0
0000
1555
0000
1555
- A
X
X
X
X
0
(hex)
Power Down STORE
t
t
DELAY
STORE
24
23
t
RECALL
22
Nonvolatile RECALL
CC
Nonvolatile STORE
STORE /Inhibit
Not Selected
exceeds V
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Write SRAM
4-57
MODE
SWITCH
. t
RECALL
Output High Z
Output High Z
Output High Z
Output High Z
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data
HSB Initiated STORE
Input Data
is measured from the point at which V
MIN
250
4.0
1
3
5
I/O
t
DELAY
t
STORE
t
24
ASSERT
23
26
MAX
300
4.5
20
10
60
UNITS
mA
ms
I
ns
ns
CC
V
A
s
s
POWER
Standby
2
Active
Active
Active
Active
/Standby
t
RECOVER
25
HSB = V
HSB = V
STK12C68-M
CC
V
Software STORE
CC
NOTES
Note o
Note e
Note e
exceeds 4.5V.
OL
IL
t
, Note e, n
STORE
, Note e, n
4.5V
NOTES
23
k,l
k,l
k,l
k,l
k,l
k,l
k,l
k,l
k,l
k,l
m
k
k
l