Click here for production status of specific part numbers. DS18B20 Programmable Resolution 1-Wire Digital Thermometer General Description Benefits and Features The DS18B20 digital thermometer provides 9-bit to Unique 1-Wire Interface Requires Only One Port 12-bit Celsius temperature measurements and has an Pin for Communication alarm function with nonvolatile user-programmable upper Reduce Component Count with Integrated and lower trigger points. The DS18B20 communicates Temperature Sensor and EEPROM over a 1-Wire bus that by definition requires only one Measures Temperatures from -55C to +125C data line (and ground) for communication with a central (-67F to +257F) microprocessor. In addition, the DS18B20 can derive 0.5C Accuracy from -10C to +85C power directly from the data line (parasite power), Programmable Resolution from 9 Bits to 12 Bits eliminating 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 Simplifies Distributed Temperature-Sensing control many DS18B20s distributed over a large area. Applications with Multidrop Capability Applications that can benefit from this feature include Each Device Has a Unique 64-Bit Serial Code HVAC environmental controls, temperature monitoring Stored in On-Board ROM systems inside buildings, equipment, or machinery, and Flexible User-Definable Nonvolatile (NV) Alarm Settings process monitoring and control systems. with Alarm Search Command Identifies Devices with Temperatures Outside Programmed Limits Applications Thermostatic Controls Available in 8-Pin SO (150 mils), 8-Pin SOP, 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 2 DS18B20 7 N.C. N.C. 1 2 3 V 3 6 N.C. DD 4 5 DQ 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. SOP 1 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 6 7/19DS18B20 Programmable Resolution 1-Wire Digital Thermometer Absolute Maximum Ratings Voltage Range on Any Pin Relative to Ground ....-0.5V to +6.0V Storage Temperature Range ............................ -55C to +125C Operating Temperature Range ......................... -55C to +125C Solder Temperature ...............................Refer to the IPC/JEDEC J-STD-020 Specification. These are stress ratings only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. DC Electrical Characteristics (-55C to +125C V = 3.0V to 5.5V) DD PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V Local power (Note 1) +3.0 +5.5 V DD Parasite power +3.0 +5.5 Pullup Supply Voltage V (Notes 1, 2) V PU Local power +3.0 V DD -10C to +85C 0.5 Thermometer Error t -30C to +100C (Note 3) 1 C ERR -55C to +125C 2 Input Logic-Low V (Notes 1, 4, 5) -0.3 +0.8 V IL The lower Local power +2.2 Input Logic-High V (Notes 1,6) of 5.5 or V IH Parasite power +3.0 V + 0.3 DD Sink Current I V = 0.4V 4.0 mA L I/O Standby Current I (Notes 7, 8) 750 1000 nA DDS Active Current I V = 5V (Note 9) 1 1.5 mA DD DD DQ Input Current I (Note 10) 5 A DQ Drift (Note 11) 0.2 C Note 1: All voltages are referenced to ground. Note 2: The Pullup Supply Voltage specification assumes that the pullup device is ideal, and therefore the high level of the pullup is equal to V . In order to meet the V spec of the DS18B20, the actual supply rail for the strong pullup transis- PU IH tor must include margin for the voltage drop across the transistor when it is turned on thus: V = V + PU ACTUAL PU IDEAL V . TRANSISTOR Note 3: See typical performance curve in Figure 1. Thermometer Error limits are 3-sigma values. Note 4: Logic-low voltages are specified at a sink current of 4mA. Note 5: To guarantee a presence pulse under low voltage parasite power conditions, V may have to be reduced to as low as ILMAX 0.5V. Note 6: Logic-high voltages are specified at a source current of 1mA. Note 7: Standby current specified up to +70C. Standby current typically is 3A at +125C. Note 8: To minimize I , DQ should be within the following ranges: GND DQ GND + 0.3V or V 0.3V DQ V . DDS DD DD Note 9: Active current refers to supply current during active temperature conversions or EEPROM writes. Note 10: DQ line is high (high-Z state). Note 11: Drift data is based on a 1000-hour stress test at +125C with V = 5.5V. DD Maxim Integrated 2 www.maximintegrated.com