Rainbow Electronics DS1629 - Manual

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FEATURES
§ Measures temperatures from -55°C to
+125°C; Fahrenheit equivalent is -67°F to
257°F
§ Real time clock counts seconds, minutes,
hours, date of the month, month, day of the
week, and year with leap year compensation
through the year 2100
§ Thermometer accuracy is ±2.0°C (typ)
§ Thermometer resolution is 9 bits (expandable)
§ Thermostatic and time alarm settings are user
definable. Dedicated open-drain Alarm output
§ 32 bytes SRAM for general data storage
§ Data is read from/written to via a 2-wire serial
interface. (open drain I/O lines)
§ Wide power supply range (2.2V - 5.5V)
§ Applications include personal
computers/PDAs, cellular telephones, office
equipment, dataloggers, or any thermally
sensitive system
§ 8-pin 150mil SOIC package
PIN ASSIGNMENT
PIN DESCRIPTION
SDA - 2-Wire Serial Data Input/Output
SCL - 2-Wire Serial Clock
GND - Ground
ALRM - Thermostat & Clock Alarm
Output
X
1
- 32.768 kHz Crystal Input
X
2
- 32.768 kHz Crystal Feedback
Output
OSC - Buffered Oscillator Output
V
DD
- Power Supply Voltage (+2.2V to
+5V)
DESCRIPTION
The DS1629 2-Wire Digital Thermometer and Real Time Clock integrates the critical functions of a real
time clock and a temperature monitor in a small outline 8-pin SOIC package. Communication to the
DS1629 is accomplished via a 2-wire interface. The wide power supply range and minimal power
requirement of the DS1629 allow for accurate time/temperature measurements in battery-powered
applications.
The digital thermometer provides 9-bit temperature readings which indicate the temperature of the device.
No additional components are required; the device is truly a “temperature-to-digital” converter.
The clock/calendar provides seconds, minutes, hours, day, date of the month, day of the week, month, and
year. The end of the month date is automatically adjusted for months with less than 31 days, including
corrections for leap years. It operates in either a 12- or 24-hour format with AM/PM indicator in 12-hour
mode.The crystal oscillator frequency is internally divided, as specified by device configuration. An
open-drain output is provided that can be used as the oscillator input for a microcontroller.
DS1629
2-Wire Digital Thermometer
and Real Time Clock
www.dalsemi.com
1
2
3
4
8
7
6
5 GND
ALRM
SCL
SDA V
DD
OSC
X
1
X
2
DS1629S 8-Pin SOIC
(150-mil)