1 of 12

022400

PRELIMINARY

DS1904

RTC iButton

www.iButton.com

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









000000FBC52B

YYWW REGISTERED RR

40

24

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

17.35

16.25

5.89

0.36

0.51