ISL12023IVZ Intersil, ISL12023IVZ Datasheet - Page 8

• Manufacturer Part Number: ISL12023IVZ
• Description: IC RTC/CLDR TEMP SNSR 14-TSSOP
• Manufacturer: Intersil
• Type: Clock/Calendarr

Specifications of ISL12023IVZ

• Memory Size: 1K (128 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: 14-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Typical Performance Curves
General Description
The ISL12023 device is a low power real time clock (RTC) with
embedded temperature sensors. It contains crystal frequency
compensation circuitry over the operating temperature range,
clock/calendar, power fail and low battery monitors, brownout
indicator with separate low voltage reset pin (LVRST),
1 periodic or polled alarm, intelligent battery-backup switching
and 128 Bytes of battery-backed user SRAM.
The oscillator uses an external, low cost 32.768kHz crystal.
The real time clock tracks time with separate registers for
hours, minutes and seconds. The device has calendar
registers for date, month, year and day of the week. The
calendar is accurate through 2099, with automatic leap year
correction. In addition, the ISL12023 could be programmed
for automatic Daylight Savings Time (DST) adjustment by
entering local DST information.
The ISL12023’s alarm can be set to any clock/calendar
value for a match. For example, every minute, every
Tuesday or at 5:23 a.m. on March 21. The alarm status is
available by checking the Status Register, or the device can
be configured to provide a hardware interrupt via the IRQ
pin. There is a repeat mode for the alarm allowing a periodic
interrupt every minute, every hour, every day, etc.
The device also offers a backup power input pin. This V
pin allows the device to be backed up by battery or super
capacitor with automatic switchover from V
ISL12023 device is specified for V
clock/calendar portion of the device remains fully operational
in battery-backup mode down to 1.8V (Standby Mode). The
V
levels. The first report is registered when the V
below 85% of nominal level, the second level is set for 75%.
Battery levels are stored in PWR_VBAT registers.
The ISL12023 offers a “Brownout” alarm once the V
below a pre-selected trip level. This allows system Micro to
save vital information to memory before complete power
BAT
100
110
90
80
70
60
50
40
level is monitored and reported against preselected
-40
FIGURE 8. I
-20
V
DD
DD
WITH TSE = 1 vs TEMPERATURE
= 5.5V
V
DD
0
TEMPERATURE (°C)
= 3.3V
8
20
DD
= 2.7V to 5.5V and the
40
Temperature is +25°C unless otherwise specified. (Continued)
DD
V
BAT
to V
BAT
60
BAT
= 2.7V
level falls
DD
. The
falls
BAT
80
ISL12023
loss. There are six V
initiation of the Brownout alarm.
Pin Descriptions
X1, X2
The X1 and X2 pins are the input and output, respectively, of
an inverting amplifier. An external 32.768kHz quartz crystal
is used with the device to supply a timebase for the real time
clock. Internal compensation circuitry with internal
temperature sensor provides frequency corrections for
selected popular crystals to ±5ppm over the operating
temperature range from -40°C to +85°C (see “Application
Section” on page 24 for recommended crystal). The
ISL12023 allows the user to input via I
temperature variation profile of an individual crystal. The
oscillator compensation network can also be used to
calibrate the initial crystal timing accuracy to less than 1ppm
error at room temperature. The device can also be driven
directly from a 32.768kHz source at pin X1.
V
This input provides a backup supply voltage to the device.
V
supply fails. The device will automatically switch to the V
input when V
Battery Monitor parameter in the electrical spec table titled
“DC Operating Characteristics-RTC” on page 3. This pin can
be connected to a battery, a super capacitor or tied to ground
if not used.
BAT
BAT
FIGURE 9. I
100
FIGURE 10. RECOMMENDED CRYSTAL CONNECTION
110
90
80
70
60
50
40
30
20
supplies power to the device in the event that the V
-40
V
BAT
DD
BAT
-20
= 5.5V
drops below a prescribed level. See the
with TSE = 1, BTSE = 1 vs TEMPERATURE
V
DD
BAT
levels that could be selected for
0
= 3.0V
TEMPERATURE (°C)
20
X1
X2
2
C serial bus the
40
V
BAT
= 1.8V
60
June 24, 2009
FN6682.2
80
BAT
DD