ISL12032IVZ-T Intersil, ISL12032IVZ-T Datasheet - Page 9

• Manufacturer Part Number: ISL12032IVZ-T
• Description: IC RTC LP BATT BACK SRAM 14TSSOP
• Manufacturer: Intersil
• Type: Clock/Calendar/NVSRAMr

Specifications of ISL12032IVZ-T

• Memory Size: 1K (128 x 8)
• Time Format: HH:MM:SS:hh (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: 14-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ISL12032IVZ-TTR

IRQ (Interrupt Output)
This pin provides an interrupt signal output. This signal
notifies a host processor that an alarm has occurred and
requests action. It is an open drain active LOW output.
F
This pin outputs a clock signal, which is related to the crystal
frequency. The frequency output is user selectable and
enabled via the I
frequencies or disable. It is a CMOS output.
Serial Clock (SCL)
The SCL input is used to clock all serial data into and out of
the device. The input buffer on this pin is always active (not
gated). It is disabled when the backup power supply on the
VBAT pin is activated to minimize power consumption.
Serial Data (SDA)
SDA is a bi-directional pin used to transfer data into and out
of the device. It has an open drain output and may be OR’ed
with other open drain or open collector outputs. The input
buffer is always active (not gated) in normal mode.
An open drain output requires the use of a pull-up resistor.
The output circuitry controls the fall time of the output signal
with the use of a slope controlled pull-down. The circuit is
designed for 400kHz I
when the backup power supply on the VBAT pin is activated.
V
Chip power supply and ground pins. The device will operate
with a power supply from V
capacitor is recommended on the V
Functional Description
Power Control Operation
The power control circuit accepts a V
Many types of batteries can be used with Intersil RTC
products. For example, 3.0V or 3.6V Lithium batteries are
appropriate, and battery sizes are available that can power
the ISL12032 for up to 10 years. Another option is to use a
Super Capacitor for applications where V
for up to a month. See the “Application Section” on page 24
for more information.
Normal Mode (V
(VBAT)
To transition from the V
following conditions must be met:
Condition 1:
V
where V
Condition 2:
V
where V
OUT
DD
DD
DD
, GND
< VBAT - V
< V
(Frequency Output)
BATHYS
TRIP
TRIP
≈ 2.2V
BATHYS
2
≈ 50mV
C bus. The options include seven different
DD
2
) to Battery Backup Mode
C interface speeds. It is disabled
DD
to VBAT mode, both of the
DD
9
= 2.7V to 5.5VDC. A 0.1µF
DD
DD
pin to ground.
and a VBAT input.
DD
is interrupted
ISL12032
Battery Backup Mode (VBAT) to Normal Mode
(V
The ISL12032 device will switch from the VBAT to V
mode when one of the following conditions occurs:
Condition 1:
V
where V
Condition 2:
V
where V
These power control situations are illustrated in Figures 3
and Figure 4.
The I
to reduce power consumption, but can be enabled by setting
the I
ISL12032 are active during battery backup mode unless
disabled via the control register.
Power Failure Detection
The ISL12032 provides a Real Time Clock Failure Bit
(RTCF) to detect total power failure. It allows users to
determine if the device has powered up after having lost all
power to the device (both V
0.0VDC). Note that in cases where the VBAT input is at 0.0V
and the V
level, the SRAM registers may not retain their values
(corrupted bits or bytes may result).
DD
DD
DD
FIGURE 3. BATTERY SWITCHOVER WHEN VBAT < V
FIGURE 4. BATTERY SWITCHOVER WHEN VBAT > V
V
VBAT
V
2
V
VBAT
V
> VBAT + V
> V
TRIP
2
TRIP
VBAT - V
CBAT bit. All the other inputs and outputs of the
DD
)
DD
C bus is normally deactivated in battery backup mode
BATHYS
TRIPHYS
TRIP
DD
BATHYS
V
input dips to <1.8V, then recovers to normal
+ V
TRIP
BATHYS
≈ 50mV
TRIPHYS
≈ 30mV
BATTERY BACKUP
BATTERY BACKUP
DD
MODE
MODE
and VBAT very near
VBAT + V
V
TRIP
+ V
BATHYS
TRIPHYS
April 16, 2009
DD
3.0V
2.2V
2.2V
1.8V
TRIP
TRIP
FN6618.2