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101107

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

2 3

NC

NC

NC

NC

GND

DQ

NC

6

8

7

5

3

1

2

4

1-Wire is a registered trademark of Dallas Semiconductor.