iButton DESCRIPTION

The DS1923 temperature/humidity logger iButton is a rugged, self-sufficient system that measures temperature and/or humidity and records the result in a protected memory section. The recording is done at a user-defined rate. A total of 8192 8-bit readings or 4096 16-bit readings taken at equidistant intervals ranging from 1s to 273hrs can be stored. In addition to this, there are 512 bytes of SRAM for storing application-specific information and 64 bytes for calibration data.

SPECIAL FEATURES

■ Digital Hygrometer Measures Humidity with 8-Bit (0.6RH) or 12-Bit (0.04RH) Resolution

■ Operating Range: -20 to +85°C; 0 to 100RH (see Safe Operating Range)

■ Automatically Wakes Up, Measures Temperature and/or Humidity and Stores Values in 8kB of Datalog Memory in 8- or 16-Bit Format

■ Digital Thermometer Measures Temperature with 8-Bit (0.5°C) or 11-Bit (0.0625°C) Resolution

■ Temperature Accuracy Better than ±0.5°C from -10°C to +65°C with Software Correction

■ Built-in Humidity Sensor for Simultaneous Temperature and Humidity Logging

■ Capacitive Polymer Humidity-Sensing Element

■ Hydrophobic Filter Protects Sensor Against Dust, Dirt, Water, and Contaminants

■ Sampling Rate from 1s up to 273hrs

■ Programmable Recording Start Delay After Elapsed Time or Upon a Temperature Alarm Trip Point

■ Programmable High and Low Trip Points for Temperature and Humidity Alarms

■ Quick Access to Alarmed Devices Through 1-Wire® Conditional Search Function

■ 512 Bytes of General-Purpose Memory Plus 64 Bytes of Calibration Memory

■ Two-Level Password Protection of All Memory and Configuration Registers

■ Communicates to Host with a Single Digital Signal at Up to 15.4kbps at Standard Speed or Up to 125kbps in Overdrive Mode Using 1-Wire Protocol

■ Individually Calibrated in a NIST-Traceable Chamber

■ Calibration Coefficients for Temperature and Humidity Factory Programmed into Nonvolatile (NV) Memory

APPLICATIONS

■ Temperature and Humidity Logging in Food Preparation and Processing

■ Transportation of Temperature- and HumiditySensitive Goods, Industrial Production

■ Warehouse Monitoring

■ Environmental Studies/Monitoring