DS18B20X Datasheet, PDF (1/21 Pages) Dallas Semiconductor – Flipchip 1-Wire Digital Thermometer

DS18B20X
Flipchip 1-Wire^® Digital Thermometer
www.dalsemi.com
FEATURES
• Unique 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
• Multi-drop 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 0°C to +70°C
• Thermometer resolution is user-selectable
from 9 to 12 bits
• Converts temperature to 12-bit digital word in
750 ms (max.)
• User-definable nonvolatile alarm settings
• Alarm search command identifies and
addresses devices whose temperature is
outside of programmed limits (temperature
alarm condition)
• Applications include thermostatic controls,
industrial systems, consumer products,
thermometers, or any thermally sensitive
system
PIN ASSIGNMENT
(TOP VIEW)
GND
VDD
28rrd
GND
DQ
Branding legend:
28 = family code
rr = revision code (i.e., B6)
d = one letter date code
See Mechanical Specification
(page 21) for package dimensions.
PIN DESCRIPTION
GND - Ground
DQ - Data In/Out
V_DD - Power Supply Voltage
DESCRIPTION
The DS18B20X Digital Thermometer provides 9 to 12–bit centigrade temperature measurements and has
an alarm function with nonvolatile user-programmable upper and lower trigger points. The DS18B20X
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 0°C to +70°C. In addition, the DS18B20X can derive power
directly from the data line (“parasite power”), eliminating the need for an external power supply.
Each DS18B20X has a unique 64-bit serial code, which allows multiple DS18B20Xs to function on the
same 1–wire bus; thus, it is simple to use one microprocessor to control many DS18B20Xs 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.
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