DS1904 Datasheet, PDF (1/12 Pages) Dallas Semiconductor – RTC iButton

www.iButton.com
PRELIMINARY
DS1904
RTC iButton
SPECIAL FEATURES
Real-Time Clock/calendar in binary format
Uses the same binary time/date representation
as the DS1994 but with 1 second resolution
Clock accuracy is better than ± 2 minutes per
month at 25°C
Operating temperature range from -40°C to
+70°C
Over 10 years of operation
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
Multidrop controller for MicroLAN
Digital identification and information by
momentary contact
Chip-based data carrier compactly stores in-
formation
Data can be accessed while affixed to object
Economically communicates to host with a
single digital signal at 16.3k bits per second
Standard 16 mm diameter and 1-Wire proto-
col ensure compatibility with iButton Device
family
Button shape is self-aligning with cup-shaped
probes
Durable stainless steel case engraved with
registration number withstands harsh envi-
ronments
Easily affixed with self-stick adhesive back-
ing, 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
5.89
0.36
0.51
16.25
YYWW REGISTERED RR
40
24
000000FBC52B
17.35
DATA
GROUND
All dimensions are shown in millimeters
ORDERING INFORMATION
DS1904L-F5
F5 MicroCan
EXAMPLES OF ACCESSORIES
DS9096P
Self-Stick Adhesive Pad
DS9101
Multi-Purpose Clip
DS9093RA
Mounting Lock Ring
DS9093A
Snap-In Fob
DS9092
iButton Probe
iButton DESCRIPTION
The DS1904 RTC iButton is a rugged real-time clock module that can be accessed with minimal
hardware. Data is transferred serially via the 1-Wire protocol, which requires only a single data lead and a
ground return. The DS1904 contains a unique 64-bit factory-lasered ROM and a real-time clock/calendar
implemented as a binary counter. The durable MicroCan package is highly resistant to environmental
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