DESCRIPTION
The DS1631, DS1631A, and DS1731 digital thermometers provide 9, 10, 11, or 12-bit temperature readings over a -55°C to +125°C range. The DS1631AU and DS1631A thermometer accuracy is 0.5°C from 0°C to +70°C with 3.0V VDD 5.5V, and the DS1731 accuracy is 1°C from -10°C to +85°C with 3.0V VDD 5.5V. The thermostat on all three devices provides custom hysteresis with user-defined trip points (TH and TL). The TH and TL registers and thermometer configuration settings are stored in NV EEPROM so they can be programmed prior to installation. In addition, the DS1631A automatically begins taking temperature measurements at power-up, which allows it to function as a stand-alone thermostat. Communication with the DS1631/DS1631A/DS1731 is achieved through a 2-wire serial interface, and three address pins allow up to eight devices to be multidropped on the same 2-wire bus.
Pin descriptions for the DS1631/DS1631A/DS1731 are provided in Table 2 and user-accessible registers are summarized in Table 3. A functional diagram is shown in Figure 1.
FEATURES
DS1631AU and DS1631A Provide 0.5°C Accuracy over a 0°C to +70°C RangeDS1731 Provides 1°C Accuracy over a -10°C to +85°C Range
DS1631A Automatically Begins Taking Temperature Measurements at Power-Up
Operating Temperature Range: -55°C to +125°C (-67°F to +257°F)
Temperature Measurements Require No External Components
Output Resolution is User-Selectable to 9,10, 11, or 12 Bits
Wide Power-Supply Range (+2.7V to +5.5V)
Converts Temperature-to-Digital Word in 750ms (max)
Multidrop Capability Simplifies Distributed Temperature-Sensing Applications
Thermostatic Settings are User-Definable and Nonvolatile (NV)
Data is Read/Written Through 2-Wire Serial Interface (SDA and SCL Pins)
All Three Devices are Available in 8-Pin SOP Packages and the DS1631AU is Also Available in a 150mil SO package—see Table 1 for Ordering Information
APPLICATIONS
Network Routers and Switches
Cellular Base Stations
Portable Products
Any Space-Constrained Thermally Sensitive Product
Feature
- Maximize System Accuracy in Broad Range of Thermal Management Applications
- Operating Temperature Range: -55°C to +125°C (-67°F to +257°F)
- DS1631 and DS1631A: ±0.5°C Accuracy over 0°C to +70°C Range
- DS1731: ±1°C Accuracy over a -10°C to +85°C Range
- User-Selectable Output Resolution from 9 Bits to 12 Bits
- Reduce Cost with No External Components
- Simplify Distributed Temperature-Sensing Applications with Multidrop Capability
- Up to Eight Devices Can Operate on a 2-Wire Bus
- Flexible and Nonvolatile User-Defined Thermostatic Modes with Custom Hysteresis
- Available in 8-Pin μSOP and SO (DS1631 and DS1631A Only) and the 8-Pin DIP (DS1631 Only) Packages
Applications
- Medical
- Networking
- Personal Computing
- Routers/Switches
- Test Measurement Systems
- Wireless Base Stations
