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

Humidity and Temperature Data-Logger Monitors Perishables Anywhere

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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

  • High Accuracy, Full-Featured Digital Temperature and Humidity Logger Simplifies Temperature Data Collection and Dissemination of Electronic Temperature Record
    • Digital Hygrometer Measures Humidity with 8-Bit (0.6%RH) or 12-Bit (0.04%RH) Resolution
    • Temperature Accuracy Better Than ±0.5°C from -10°C to +65°C with Software Correction
    • Measures Temperature with 8-Bit (0.5°C) or 11-Bit (0.0625°C) Resolution
    • Operating Range: -20°C to +85°C; 0 to 100% RH (see Safe Operating Range Graph)
    • Automatically Wakes Up, Measures Temperature and/or Humidity, and Stores Values in 8kB of Data-Log Memory in 8-Bit or 16-Bit Format
    • Built-In Capacitive Polymer Humidity Sensor for Humidity Logging
    • Sampling Rate from 1s Up to 273hr
    • Programmable High and Low Trip Points for Temperature and Humidity Alarms
    • Programmable Recording Start Delay After Elapsed Time or Upon a Temperature Alarm Trip Point
    • 512 Bytes of General-Purpose Memory Plus 64 Bytes of Calibration Memory
    • Two-Level Password Protection of All Memory and Configuration Registers
    • Individually Calibrated in a NIST-Traceable Chamber
    • Calibration Coefficients for Temperature and Humidity Factory Programmed Into Nonvolatile (NV) Memory
  • Rugged Construction Survives Harsh Environments
    • Hydrophobic Filter Protects Sensor Against Dust, Dirt, Contaminants, and Water Droplets/ Condensation with IP56 Enclosure Rating
    • CE, FCC, and UL913 Certifications
  • Simple Serial Port Interfaces to Most Microcontrollers for Rapid Data Transfer
    • Communicates to Host with a Single Digital Signal Up to 15.4kbps at Standard Speed or Up to 125kbps in Overdrive Mode Using 1-Wire Protocol
    • Quick Access to Alarmed Devices Through 1-Wire Conditional Search Function


  • Environmental Studies/Monitoring
  • Temperature and Humidity Logging in Food Preparation and Processing
  • Transportation of Temperature- and Humidity-Sensitive Goods, Industrial Production
  • Warehouse Monitoring
Part NumberInterfaceTechnologyApplicationsUsageMemory TypeMemory SizeData Logger TypeTemp. Readings Oper. Temp.
See Notes
DS1923 1-WireiButtonAsset ManagementMulti UseSRAM512 Bytes
8192-20 to +85$84.88 @1k
See All Data Loggers (10)
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.

Technical Documents

App Note 5917 Instructions for Compiling the OneWireViewer for Linux
App Note 5916 iButton Mission Data Recovery: memlog User Guide
App Note 5705 Interface 1-Wire USB Adapter with Android
App Note 5507 Understanding the DS1WM Synthesizable 1-Wire Bus Master
Tutorial 5405 Choosing the Logger iButton That's Right for You
App Note 5335 Determining the Mission Parameters for Temperature Logger iButton® Devices
App Note 4629 iButton Data-Logger Calibration and NIST Certificate FAQs
Reference Schematic 4477 Reference Design of a 1-Wire® Bidirectional Voltage-Level Translator for 1.8V to 5V
App Note 4126 Understanding the IP (Ingress Protection) Ratings of iButton Data Loggers and Capsule
App Note 3892 Overview of iButton® Sensors and Temperature/Humidity Data Loggers
App Note 3845 The MAXQ Microcontroller in Action: Designing a Bicycle Computer with the MAXQ2000
App Note 3809 Exporting DS192x Logger Data from the OneWireViewer into Excel
App Note 3808 What Is an iButton Device?
App Note 3761 DS1922/DS1923 Battery Gas Gauge
App Note 159 Software Methods to Achieve Robust 1-Wire® Communication in iButton® Applications
App Note 158 1-Wire® Tagging with XML
App Note 155 1-Wire Software Resource Guide Device Description
Tutorial 148 Guidelines for Reliable Long Line 1-Wire Networks
App Note 126 1-Wire Communication Through Software
App Note 114 1-Wire File Structure
App Note 74 Reading and Writing 1-Wire® Devices Through Serial Interfaces

Quality and Environmental Data

Product Reliability Reports: DS1923.pdf 
Lead-Free Package Tin (Sn) Whisker Reports
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

Quality Management System >
Environmental Management System >

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