DS1904_11 Datasheet, PDF (1/13 Pages) Maxim Integrated Products – Real-Time Clock/calendar in binary format RTC iButton Over 10 years of operation

19-4864; Rev 4/11
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 16.3 kbps
 Standard 16 mm diameter and 1-Wire^®
protocol 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, 5th Ed., Rev. 1997-02-24;
Intrinsically Safe Apparatus, Approved under
Entity Concept for use in Class I, Division 1,
Group A, B, C, and D Locations
F5 MicroCan
5.89
0.51

16.25
40
 24
000000FBC52B
1-Wire^
17.35
IO
GND
All dimensions are shown in millimeters
ORDERING INFORMATION
DS1904L-F5# F5 MicroCan
# Denotes an RoHS-compliant device that may include
lead(Pb) that is exempt under the RoHS requirements.
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
1-Wire and iButton are registered trademarks of Maxim Integrated Products, Inc.
1 of 13