ISL12024IBZ-T Intersil, ISL12024IBZ-T Datasheet - Page 14

• Manufacturer Part Number: ISL12024IBZ-T
• Description: IC RTC/CALENDAR EEPROM 8-SOIC
• Manufacturer: Intersil
• Type: Clock/Calendar/EEPROMr

Specifications of ISL12024IBZ-T

• Memory Size: 4K (512 x 8)
• Time Format: HH:MM:SS (12/24 hr)
• Date Format: YY-MM-DD-dd
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Rohs Compliant: YES
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ISL12024IBZ-TTR

about 90ms following the power-up. To trigger the delay, the
VDD must drop below the battery trip point, yet stay above
approximately 1.0V (limit of active circuit operation). After
that, the power-up ramp must be slower than 0.25V/ms to
trigger the delay. To be safe, serial interface software may be
needed to consider the 90ms delay in all power-up routines.
OPTION 1 - STANDARD (POWER CONTROL) MODE
In the Standard Mode, the supply will switch over to the
battery when V DD drops below V
lower. In this mode, accidental operation from the battery is
prevented since the battery backup input will only be used
when the V DD supply is shut off.
To select Option 1, BSW bit in the Power Register must be
set to “BSW = 0”. A description of power switchover is as
follows:
Standard Mode Power Switchover
• Normal Operating Mode (V
• Battery Backup Mode (V
There are two discrete situations that are possible when
using Standard Mode: V BAT < V TRIP and V BAT > V TRIP .
These two power control situations are illustrated in Figures
9 and 10.
(V
To transition from the V
following conditions must be met:
- Condition 1:
- Condition 2:
The ISL12024 device will switch from the V
mode when one of the following conditions occurs:
- Condition 1:
- Condition 2:
FIGURE 9. BATTERY SWITCHOVER WHEN V
V
V
BAT
V
where V
V
where V
V
where V
V
where V
TRIP
BAT
V
DD
DD
DD
DD
DD
V
BAT
)
< V
< V
> V
> V
- V
BATHYS
TRIP
BATHYS
TRIPHYS
BAT
TRIP
BAT
TRIP
BATHYS
- V
+ V
≈ 2.2V
+ V
BATHYS
BATHYS
≈ 50mV
≈ 50mV
TRIPHYS
≈ 30mV
DD
BAT
BATTERY
BACKUP
14
to V
DD
MODE
) to Normal Mode (V
) to Battery Backup Mode
TRIP
BAT
mode, both of the
or V
BAT
V
BAT
BAT
, whichever is
BAT
+ V
to V
< V
DD
BATHYS
TRIP
2.2V
1.8V
DD
)
ISL12024
OPTION 2 - LEGACY (POWER CONTROL) MODE
(DEFAULT)
The Legacy Mode follows conditions set in X1226 products.
In this mode, switching from V
comparing the voltages and the device operates from
whichever is the higher voltage. Care should be taken when
changing from Normal to Legacy Mode. If the V
higher than V
and unless the battery is disconnected or the voltage
decreases, the device will no longer operate from V
To select Option 2, the BSW bit in the Power Register must
be set to “BSW = 1”.
• Normal Mode (V
• Battery Backup Mode (V
The Legacy Mode power control conditions are illustrated in
Figure 11.
Serial Communication
The device supports the I
Clock and Data
Data states on the SDA line can change only during SCL
LOW. SDA state changes during SCL HIGH are reserved for
indicating start and stop conditions (see Figure 12).
V
To transition from the V
conditions must be met:
V
The device will switch from the V
the following condition occurs:
V
FIGURE 10. BATTERY SWITCHOVER WHEN V
BAT
V
V
FIGURE 11. BATTERY SWITCHOVER IN LEGACY MODE
DD
DD
V
BAT
TRIP
DD
< V
> V
BAT
BAT
V
DD
TRIP
- V
+V
OFF
, then the device will enter battery backup
BATHYS
BATHYS
DD
) to Battery Backup Mode (V
V
BATTERY BACKUP
DD
2
DD
C protocol.
BAT
MODE
to V
DD
) to Normal Mode (V
to V
BAT
BAT
VOLTAGE
BAT
mode, the following
to V
is simply done by
V
TRIP
DD
BAT
BAT
+ V
mode when
ON
August 18, 2008
TRIPHYS
BAT
DD
voltage is
> V
DD
3.0V
2.2V
.
FN6370.3
TRIP
)
)
In