Preliminary
NONVOLATILE MEMORY OPERATIONS
MODE SELECTION
E
W
H
X
L
H
L
L
A8 - A0
(hex)
X
X
X
k: reserved for future development
l: reserved for future development
m: I/O state assumes that G ≤ VIL.
Mode
Not Selected
Read SRAM
Write SRAM
I/O
Output High Z
Output Data
Input Data
U636H04
Power
Standby
Active
Active
Notes
m
No.
PowerStore
Power Up RECALL
24 Power Up RECALL Durationn, e
Symbol
Alt.
IEC
tRESTORE
25 STORE Cycle Durationf
tPDSTORE
26
Time allowed to Complete SRAM
Cyclef, e
Low Voltage Trigger Level
tDELAY
VSWITCH
Conditions
Min. Max. Unit
the power supply vol-
tage must stay above
3.6 V for at least
10 ms after the start
of the STORE
operation
650 µs
10 ms
1
µs
4.0 4.5 V
n: An automatic RECALL also takes place at power up, starting when VCC exceeds VSWITCH and takes tRESTORE. VCC must not drop below
VSWITCH once it has been exceeded for the RECALL to function properly.
December 12, 1997
7