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