General Description
The DS1857 dual temperature-controlled nonvolatile (NV) variable resistors with external temperature input and monitors consists of two 50kΩ 256-position linear variable resistors, two analog monitor inputs (MON1, MON2), and an external temperature sensor input. The device provides an ideal method for setting and temperature-compensating bias voltages and currents in control applications using minimal circuitry. The variable resistor settings are stored in EEPROM memory and can be accessed over the 2-wire serial bus.

Features
♦ Four Total Monitored Channels (Temperature, VCC, MON1, MON2)
♦ Two External Analog Inputs (MON1, MON2)
♦ Interface to External Temperature Sensor (LM50)
♦ Two 50kΩ, Linear, 256-Position, Nonvolatile Temperature-Controlled Variable Resistors
♦ Resistor Settings Changeable Every 2°C
♦ Access to Monitoring and ID Information Configurable with Separate Device Addresses
♦ Resistor Disable (Open-Circuit) Function
♦ 2-Wire Serial Interface
♦ Three Address Lines for Multiple Devices
♦ Operates from a 3.3V or 5V Supply
♦ SFF-8472 Compatible

Applications
    Optical Transceivers
    Optical Transponders
    Instrumentation and Industrial Controls
    RF Power Amps
    Diagnostic Monitoring