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061002

FEATURES

§ Unique 1-Wire

port pin for communication.

§ Each device has a unique 64-bit serial code

stored in an on-board ROM.

§ Multidrop capability simplifies distributed

temperature-sensing applications.

§ Requires no external components.

§ Can be powered from data line. Power supply

range is 3.0V to 5.5V.

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

(-67°F to +257°F).

§ ±2.0°C accuracy from -10°C to +85°C.

§ Thermometer resolution is user-selectable

from 9 to 12 bits.

§ Converts temperature to 12-bit digital word in

750ms (max.)

§ User-definable nonvolatile (NV) alarm

settings.

§ Alarm search command identifies and

addresses devices whose temperature is

outside of programmed limits (temperature

alarm condition).

§ Software compatible with the DS18B20.

§ Applications include thermostatic controls,

industrial

systems,

consumer

products,

thermometers, or any thermally sensitive

system.

PIN ASSIGNMENT

PIN DESCRIPTION

GND - Ground

DQ

- Data In/Out

- Power Supply Voltage

NC

- No Connect

DESCRIPTION

The DS1822 digital thermometer provides 9- to 12-bit centigrade temperature measurements and has an

alarm function with NV user-programmable upper and lower trigger points. The DS1822 communicates

over a 1-Wire bus that by definition requires only one data line (and ground) for communication with a

central microprocessor. It has an operating temperature range of –55°C to +125°C and is accurate to

±2.0°C over the range of –10°C to +85°C. In addition, the DS1822 can derive power directly from the

data line (“parasite power”), eliminating the need for an external power supply.

Each DS1822 has a unique 64-bit serial code, which allows multiple DS1822s to function on the 1-Wire

bus; thus, it is simple to use one microprocessor to control many DS1822s distributed over a large area.

Applications that can benefit from this feature include HVAC environmental controls, temperature

monitoring systems inside buildings, equipment or machinery, and process monitoring and control

systems.

1

(BOTTOM VIEW)

2 3

DS1822

Econo 1-Wire Digital

Thermometer

www.maxim-ic.com

8-Pin 150mil SO

(DS1822Z)

TO-92

(DS1822)

DALLAS

1822

1 23

NC

NC

NC

NC

GND

DQ

NC

6

8

7

5

3

1

2

4

1-Wire is a registered trademark of Dallas Semiconductor.