Datasheet

M41T00S Operation
Doc ID 10772 Rev 5 11/28
2.4 Data retention mode
With valid V
CC
applied, the M41T00S can be accessed as described above with READ or
WRITE cycles. Should the supply voltage decay, the power input will be switched from the
V
CC
pin to the battery when V
CC
falls below the battery backup switchover voltage (V
SO
). At
this time the clock registers will be maintained by the attached battery supply. On power-up,
when V
CC
returns to a nominal value, write protection continues for t
REC
.
For a further, more detailed review of lifetime calculations, please see Application Note
AN1012.
Figure 9. WRITE mode sequence
AI00591
BUS ACTIVITY:
ACK
S
ACK ACK ACK ACK
STOP START
PSDA LINE
BUS ACTIVITY:
MASTER
R/W
DATA n DATA n+1 DATA n+X
WORD
ADDRESS (An)
SLAVE
ADDRESS