iButton 1990A

i1990A SPECIAL FEATURES

nbsp;Upgrade of DS1990 allows multiple Serial Number iButtons to

reside on a common bus

nbsp;Unique 48bit serial number

nbsp;Low-cost electronic key for access control

nbsp;8-bit CRC for checking data integrity

nbsp;Can be read in less than 5 ms

nbsp;Operating temperature range of -40°C to +85°C

COMMON iButton FEATURES

nbsp;Unique, factory-lasered and tested 64-bit

registration number (8-bit family code + 48

bit serial number + 8bit CRC tester) assures

absolute traceability because no two parts are

alike.

nbsp;Multidrop controller for MicroLAN.

nbsp;Digital identification by momentary contact.

nbsp;Chip-based data carrier compactly stores information.

nbsp;Data can be accessed while affixed to an object.

nbsp;Economically communicates to bus master with a single digital signal at 16.3k bits per second.

nbsp;Standard 16 mm diameter and 1-Wire protocol ensure compatibility with iButton family.

nbsp;Button shape is self-aligning with cupshaped probes.

nbsp;Durable stainless steel case engraved with registration number withstands harsh environments.

nbsp;Easily affixed with self-stick adhesive backing, latched by its flange, or locked with a ring pressed onto its rim.

nbsp;Presence detector acknowledges when reader first applies voltage. &nbsp