Rainbow Electronics DS1920 - Manual

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SPECIAL FEATURES
§ Digital thermometer measures temperatures
from -55°C to +100°C in typically 0.2
seconds
§ Zero standby power
§ 0.5°C resolution, digital temperature reading
is two’s complement of °C value
§ Access to internal counters allows increased
resolution through interpolation
§ Reduces control, address, data, and power to
a single data contact
§ 8-bit device-generated CRC for data integrity
§ 8-bit family code specifies DS1920
communications requirements to reader
§ Special command set allows user to skip
ROM section and do temperature
measurements simultaneously for all devices
on the bus
§ 2 bytes of EEPROM to be used either as
alarm triggers or user memory
§ Alarm search directly indicates which device
senses alarming temperatures
COMMON iButton FEATURES
§ Unique, factory-lasered and tested 64-bit
registration number (8-bit family code + 48-
bit serial number + 8-bit CRC tester) assures
absolute traceability because no two parts are
alike
F3 MICROCAN
TM
§ Multidrop controller for MicroLAN
§ Digital identification and information by
momentary contact
§ Chip-based data carrier compactly stores
information
§ Data can be accessed while affixed to object
§ Economically communicates to bus master
with a single digital signal at 16.3k bits per
second
§ Standard 16 mm diameter and 1-Wire TM
protocol ensure compatibility with iButton
family
§ Button shape is self-aligning with cup-
shaped probes
§ Durable stainless steel case engraved with
registration number withstands harsh
environments
§ Easily affixed with self-stick adhesive
backing, latched by its flange, or locked with
a ring pressed onto its rim
§ Presence detector acknowledges when reader
first applies voltage
§ Meets UL#913 (4th Edit.); Intrinsically Safe
Apparatus, approved under Entity Concept
for use in Class I, Division 1, Group A, B, C
and D Locations (application pending)
F5 MICROCAN
TM
All dimensions are shown in millimeters
DS1920
Temperature iButton

www.dalsemi.com
DATA
GROUND
0.36
0.51
3.10
c 1993
YYWW REGISTERED RR
A0 10
000000FBC52B
16.25
17.35
DATA
GROUND
0.36 0.51
5.89
c 1993
YYWW REGISTERED RR
20 10
000000FBD8B3
16.25
17.35