DESCRIPTION

The DS18B20 digital thermometer provides 9-bit to

12-bit Celsius temperature measurements and has an

alarm function with nonvolatile user- programmable

upper and lower trigger points. The DS18B20

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 ±0.4°C over the range of -10°C to

+70°C. In addition, the DS18B20 can derive power

directly from the data line (“parasite power”),

eliminating the need for an external power supply.

Each DS18B20 has a unique 64-bit serial code,

which allows multiple DS18B20s to function on the

same 1-Wire bus. Thus, it is simple to use one

microprocessor to control many DS18B20s

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.

FEATURES

? 1-Wire Interface Requires Only One 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 2.5V to 5.5V

? Measures Temperatures from -55°C to +125°C

(-67°F to +257°F)

? ±0.4°C Accuracy from -10°C to +70°C

? Thermometer Resolution is User Selectable

from 9 to 12 Bits

? Converts Temperature to 12-Bit Digital Word in

400ms (Max)

? User-Definable Nonvolatile (NV) Alarm Settings

? Alarm Search Command Identifies and

Addresses Devices Whose Temperature

is Outside Programmed Limits

? Available in 8-Pin SOJ8 and 3-Pin TO-92

Packages

? Applications Include Thermostatic

Controls, Industrial Systems, Consumer

Products, Thermometers, or Any

Thermally Sensitive System

? ESD Rating: HBM8000V, MM800V