General Description

The DS1921G Thermochron®iButton®is a rugged, selfsufficient system that measures temperature and records

the result in a protected memory section. The recording is done at a user-defined rate, both as a direct storage of temperature values as well as in the form of a histogram.

Features

♦Digital Thermometer Measures Temperature in 0.5°C Increments

♦Accuracy ±1°C from -30°C to +70°C (See the Electrical Characteristicsfor Accuracy Specification)

♦Built-In Real-Time Clock (RTC) and Timer Has Accuracy of ±2 Minutes per Month from 0°C to +45°C

♦Water Resistant or Waterproof if Placed Inside DS9107 iButton Capsule (Exceeds Water Resistant 3 ATM Requirements)

♦Automatically Wakes Up and Measures Temperature at User-Programmable Intervals from 1 Minute to 255 Minutes

♦Logs Consecutive Temperature Measurements in 2KB of Data-Log Memory

♦Records a Long-Term Temperature Histogram with 2.0°C Resolution

♦Programmable Temperature High and Temperature Low Alarm Trip Points

♦Records Up to 24 Timestamps and Durations When Temperature Leaves the Range Specified by the Trip Points

♦512 Bytes of General-Purpose Battery-Backed SRAM

♦Communicates to Host with a Single Digital Signal at 15.4kbps or 125kbps Using 1-Wire Protocol

Applications

Temperature Logging in Cold Chain, Food Safety, Pharmaceutical, and Medical Products