iButton Hygrochron Temperature/Humidity Logger with 8KB Data-Log Memory

Humidity and Temperature Data-Logger Monitors Perishables Anywhere


The iButton® temperature/humidity logger (DS1923) 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. A mission to collect data can be programmed to begin immediately, or after a user-defined delay or after a temperature alarm. Access to the memory and control functions can be password-protected. The DS1923 is configured and communicates with a host-computing device through the serial 1-Wire® protocol, which requires only a single data lead and a ground return. Every DS1923 is factory-lasered with a guaranteed unique 64-bit registration number that allows for absolute traceability. The durable stainless-steel package is highly resistant to environmental hazards such as dirt, moisture, and shock. Accessories permit the DS1923 to be mounted on almost any object, including containers, pallets and bags.

Key Features

  • Digital Hygrometer Measures Humidity with 8-Bit (0.6%RH) or 12-Bit (0.04%RH) Resolution
  • Operating Range: -20°C to +85°C; 0 to 100%RH (see Safe Operating Range Graph in the full data sheet)
  • Automatically Wakes Up, Measures Temperature and/or Humidity and Stores Values in 8KB of Data-Log 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, Contaminants, and Water Droplets/Condensation
  • 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


  • Environmental Studies/Monitoring
  • Temperature and Humidity Logging in Food Preparation and Processing
  • Transportation of Temperature- and Humidity-Sensitive Goods, Industrial Production
  • Warehouse Monitoring
Part Number Interface Technology Applications Usage Memory Type Memory Size Data Logger Type Temp. Readings Oper. Temp.
See Notes
DS1923  1-Wire iButton Asset Management Multi Use NV SRAM 512 Bytes
8192 -20 to +85 $79.07 @1k
See All Data Loggers (9)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Part Number Technology Applications Memory Type Memory Size Data Logger Type Data Logger Size Data Logger Sample Rate Data Logger Accuracy Data Logger Resolution Data Logger Measuremt. Range Security Features Prog. Alarm Unique Ware Real Time Clock Oper. Temp.
See Notes
DS1923  iButton Asset Management NV SRAM 512 Bytes
8192 Byte 1s to 273hrs Correctible to ±0.5°C Selectable 8-bit (0.5°C) or 11-bit (0.0625°C)
-20°C to +85°C
0 to 100%RH
Password Protected
Humidity High/Low
Temperature High/Low
No Yes -20 to +85 $79.07 @1k
See All iButton Products (26)


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