AVAILABLE

Functional Diagrams

Pin Configurations appear at end of data sheet.

Functional Diagrams continued at end of data sheet.

UCSP is a trademark of Maxim Integrated Products, Inc.

For pricing, delivery, and ordering information, please contact Maxim Direct

at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.

FEATURES

§ Temperature measurements require no

external components

§ Measures temperatures from -55°C to +125°C

in 0.5°C increments. Fahrenheit equivalent is

-67°F to 257°F in 0.9°F increments

§ Temperature is read as a 9-bit value (2-byte

transfer)

§ Wide power supply range (2.7V to 5.5V)

§ Converts temperature to digital word in less

than 1 second

§ Thermostatic settings are user definable and

nonvolatile

§ Data is read from/written via a 2-wire serial

interface (open drain I/O lines)

§ Applications include thermostatic controls,

industrial systems, consumer products,

thermometers, or any thermal sensitive

system

§ 8-pin DIP or SO package (150mil and

208mil)

PIN ASSIGNMENT

PIN DESCRIPTION

SDA

- 2-Wire Serial Data Input/Output

SCL

- 2-Wire Serial Clock

GND

- Ground

- Thermostat Output Signal

A0

- Chip Address Input

A1

- Chip Address Input

A2

- Chip Address Input

- Power Supply Voltage

DESCRIPTION

The DS1621 Digital Thermometer and Thermostat provides 9-bit temperature readings, which indicate

device exceeds a user-defined temperature TH. The output remains active until the temperature drops

below user defined temperature TL, allowing for any hysteresis necessary.

User-defined temperature settings are stored in nonvolatile memory so parts may be programmed prior to

insertion in a system. Temperature settings and temperature readings are all communicated to/from the

DS1621 over a simple 2-wire serial interface.

DS1621

Digital Thermometer and Thermostat

6

3

1

2

4

8

7

5

SDA

GND

DS1621S 8-PIN SO (150mil)

DS1621V 8-PIN SO (208mil)

6

3

1

2

4

8

7

5

SDA

SCL

GND

DS1621 8-PIN DIP (300mil)

SCL

090905