1-Wire Digital Temperature Sensor with 1Kb Lockable EEPROM

The MAX31826 digital thermometer provides 12-bit temperature measurements and communicates over a 1-Wire® bus that by definition requires only one data line (and ground) for communication with a central microcontroller. It has a -55°C to +125°C operating temperature range and is accurate to ±0.5°C over the -10°C to +85°C range. In addition, the device can derive power directly from the data line ("parasite power"), eliminating the need for an external power supply.

Each device has a unique 64-bit serial code, which allows multiple devices to function on the same 1-Wire bus. Therefore, it is simple to use one microcontroller (the master device) to control many devices distributed over a large area. The device includes 128 bytes (1Kb) of EEPROM for storage of system data. The EEPROM can be locked to permanently prevent any further data writes. Four location address inputs simplify mapping of individual devices to specific locations.

Applications

* Building Automation * Consumer Equipment * Industrial Systems * Module Identification * System Calibration

* Unique 1-Wire Interface Requires Only One Port Pin for Communication

* Integrated Temperature Sensor and EEPROM Reduce Component Count

* Measures Temperatures from -55°C to +125°C (-67°F to +257°F)

* ±0.5°C Accuracy from -10°C to +85°C

* 12-Bit Temperature Resolution (0.0625°C)

* 1Kb EEPROM Can Be Locked to Prevent Further Writes

* Multidrop Capability Simplifies Multisensor Systems

* Each Device Has a Unique 64-Bit Serial Code Stored in On-Board ROM

* Four Pin-Programmable Bits to Uniquely Identify Up to 16 Sensor Locations on a Bus

* Can Be Powered from Data Line (3.0V to 3.7V Power-Supply Range)

* 8-Pin µMAX® and TDFN Packages