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101207
FEATURES
" Unique 1-Wire
?/DIV>
interface requires only one
port pin for communication
" Derives power from data line (parasite
power)does not need a local power supply
" Multi-drop capability simplifies distributed
temperature sensing applications
" Requires no external components
" ?.5癈 accuracy from 10癈 to +85癈
" Measures temperatures from 55癈 to
+100癈 (67癋 to +212癋)
" Thermometer resolution is user-selectable
from 9 to 12 bits
" Converts temperature to 12-bit digital word in
750 ms (max.)
" Userdefinable non-volatile temperature
alarm settings
" Alarm search command identifies and
addresses devices whose temperature is
outside of programmed limits (temperature
alarm condition)
" Software compatible with the DS1822-PAR
" Ideal for use in remote sensing applications
(e.g., temperature probes) that do not have a
local power source
PIN ASSIGNMENT
PIN DESCRIPTION
GND - Ground
DQ - Data In/Out
NC - No Connect
DESCRIPTION
The DS18B20-PAR digital thermometer provides 9 to 12bit centigrade temperature measurements and
has an alarm function with nonvolatile user-programmable upper and lower trigger points. The
DS18B20-PAR does not need an external power supply because it derives power directly from the data
line (parasite power). The DS18B20-PAR communicates over a 1-Wire bus, which by definition
requires only one data line (and ground) for communication with a central microprocessor. It has an
operating temperature range of 55癈 to +100癈 and is accurate to ?.5癈 over a range of 10癈 to
+85癈.
Each DS18B20-PAR has a unique 64-bit identification code, which allows multiple DS18B20-PARs to
function on the same 1wire bus; thus, it is simple to use one microprocessor to control many DS18B20-
PARs 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.
DS18B20-PAR
1-Wire Parasite-Power
Digital Thermometer
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TO-92
DS18B20-PAR
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BOTTOM VIEW
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DALLAS
18B20P
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1-Wire is a registered trademark of Dallas Semiconductor.