Operating modes
M48Z35, M48Z35Y
For more information on Battery Storage Life refer to the Application Note AN1012.
Figure 8.
Power down/up mode AC waveforms
VCC
VPFD (max)
VPFD (min)
VSO
tF
tFB
tPD
INPUTS
RECOGNIZED
tR
tRB
tDR
DON'T CARE
trec
RECOGNIZED
HIGH-Z
OUTPUTS
VALID
(PER CONTROL INPUT)
VALID
(PER CONTROL INPUT)
AI01168C
Table 5.
Symbol
t
PD
t
F(2)
t
FB(3)
t
R
t
RB
t
rec
Power down/up AC characteristics
Parameter
(1)
E or W at V
IH
before power down
V
PFD
(max) to V
PFD
(min) V
CC
fall time
V
PFD
(min) to V
SS
V
CC
fall time
V
PFD
(min) to V
PFD
(max) V
CC
rise time
V
SS
to V
PFD
(min) V
CC
rise time
V
PFD
(max) to inputs recognized
Min
0
300
10
10
1
40
200
Max
Unit
µs
µs
µs
µs
µs
ms
1. Valid for ambient operating temperature: T
A
= 0 to 70°C; V
CC
= 4.75 to 5.5V or 4.5 to 5.5V (except where noted).
2. V
PFD
(max) to V
PFD
(min) fall time of less than t
F
may result in deselection/write protection not occurring until 200µs after
V
CC
passes V
PFD
(min).
3. V
PFD
(min) to V
SS
fall time of less than t
FB
may cause corruption of RAM data.
Table 6.
Symbol
V
PFD
V
SO
t
DR(2)
Power down/up trip points DC characteristics
Parameter
(1)
Power-fail deselect voltage
Battery back-up switchover voltage
Expected data retention time
M48Z35
M48Z35Y
M48Z35/Y
10
Min
4.5
4.2
Typ
4.6
4.35
3.0
Max
4.75
4.5
Unit
V
V
V
YEARS
1. Valid for ambient operating temperature: T
A
= 0 to 70°C; V
CC
= 4.75 to 5.5V or 4.5 to 5.5V (except where noted).
2. At 25°C, V
CC
= 0V.
Note:
All voltages referenced to V
SS
.
12/23
STMICROELECTRONICS [ STMICROELECTRONICS ]
