Datasheet DS18B20

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DS18B20 Programmable Resolution 1-Wire Digital Thermometer General Description Benefits and Features
The DS18B20 digital thermometer provides 9-bit to 12-bit ● Unique 1-Wire® Interface Requires Only One Port Celsius temperature measurements and has an alarm Pin for Communication function with nonvolatile user-programmable upper and ● Reduce Component Count with Integrated lower trigger points. The DS18B20 communicates over a Temperature Sensor and EEPROM 1-Wire bus that by definition requires only one data line • Measures Temperatures from -55°C to +125°C (and ground) for communication with a central micro- (-67°F to +257°F) processor. In addition, the DS18B20 can derive power • ±0.5°C Accuracy from -10°C to +85°C directly from the data line (“parasite power”), eliminating • Programmable Resolution from 9 Bits to 12 Bits the need for an external power supply. • No External Components Required Each DS18B20 has a unique 64-bit serial code, which ● Parasitic Power Mode Requires Only 2 Pins for allows multiple DS18B20s to function on the same 1-Wire Operation (DQ and GND) bus. Thus, it is simple to use one microprocessor to control many DS18B20s distributed over a large area. ● Simplifies Distributed Temperature-Sensing Applications that can benefit from this feature include Applications with Multidrop Capability HVAC environmental controls, temperature monitoring • Each Device Has a Unique 64-Bit Serial Code systems inside buildings, equipment, or machinery, and Stored in On-Board ROM process monitoring and control systems. ● Flexible User-Definable Nonvolatile (NV) Alarm Settings with Alarm Search Command Identifies Devices with
Applications
Temperatures Outside Programmed Limits ● Thermostatic Controls ● Available in 8-Pin SO (150 mils), 8-Pin µSOP, and ● Industrial Systems 3-Pin TO-92 Packages ● Consumer Products ● Thermometers
Pin Configurations
● Thermally Sensitive Systems TOP VIEW
+
N.C. 1 8 N.C.
DS18B20
N.C. 2
DS18B20
7 N.C. 1 2 3 VDD 3 6 N.C. DQ 4 5 GND
SO (150 mils) (DS18B20Z)
DQ 1
+
8 VDD GND DQ VDD N.C. 2 7 N.C.
DS18B20
N.C. 3 6 N.C. 1 2 3 GND 4 5 N.C. 1
µSOP
BOTTOM VIEW
(DS18B20U) Ordering Information appears at end of data sheet. TO-92 (DS18B20)
1-Wire is a registered trademark of Maxim Integrated Products, Inc. 19-7487; Rev 4; 1/15