ISL12024 Intersil Corporation, ISL12024 Datasheet - Page 23

• Manufacturer Part Number: ISL12024
• Description: Real-Time Clock/Calendar
• Manufacturer: Intersil Corporation

• Mode B - In this mode selection, bits indicate Legacy
• Mode C - This mode combines Standard Mode battery
B (X1226
Mode switchover combined with I
Backup Mode. When the V
the device will enter Battery Backup Mode. If the
microcontroller and bus pullups are also powered by the
battery, then the ISL12024 can communicate in Battery
Backup Mode. This mode places the ISL12024 device in
the same operating mode as the X1226 legacy device.
switchover with no I
When the V
V
MODE
Mode)
BAT
C
D
A
, then the device will enter Battery Backup Mode and
SBIB BIT
DD
0
0
1
1
voltage drops below the lower of V
2
C operation in Battery Backup Mode.
BSW BIT
0
1
0
1
23
DD
voltage drops below V
2
V
V
Standard Mode,
Standard Mode,
C operation in Battery
SWITCHOVER
Legacy Mode,
Legacy Mode,
TRIP
TRIP
V
V
VOLTAGE
DD
DD
V
= 2.2V typ
= 2.2V typ
BAT
< V
< V
BAT
BAT
TRIP
I
2
C ACTIVE IN
BACKUP?
BAT
BATTERY
or
Yes
Yes
NO
NO
ISL12024
,
TABLE 8.
WRITE/READ
IN BATTERY
BACKUP?
EE PROM
• Mode D - This mode combines Legacy Mode battery
Note that the IRQ/F
battery backup for all modes, allowing clocking of devices
while in Battery Backup Mode. The pullup on the pin will
need to go to V
increase accordingly.
the I
drain.
switchover with no I
When the V
enter Battery Backup Mode and the I
disabled, minimizing V
NO
NO
NO
NO
2
C interface will be disabled, minimizing V
pullup to V
pullup to V
pullup to V
pullup to V
YES, needs
YES, needs
YES, needs
YES, needs
DD
FREQ/IRQ
ACTIVE?
BAT
voltage drops below V
, and thus battery mode current draw will
OUT
2
BAT
BAT
BAT
BAT
C operation in Battery Backup Mode.
open drain output pin is active in
BAT
V
V
to operate in Battery Backup.
V
needed on I
Battery Backup.
V
V
V
BAT
TRIP
BAT
BAT
TRIP
BAT
current drain.
switchover at lower of V
. Pullups needed on I
switchover at <V
switchover at lower of V
.
switchover at <V
2
C to V
2
BAT
NOTES
C interface will be
, the device will
BAT
DD
DD
to operate in
October 18, 2006
BAT
. Pullups
.
2
C to V
current
BAT
BAT
FN6370.1
BAT
or
or