DS3906

Features:

 Three Programmable Resistors for Low Step-SizeApplications (Ohm and Subohm)
Resistor Settings are NV
16-Byte NV User Memory (EEPROM)
I2C-Compatible Serial Interface
Up to 8 Devices Can be Multidropped on theSame I2C Bus
Low Power Consumption
Wide Operating Voltage (2.7V to 5.5V)
Operating Temperature Range: -40 to +85


Pinout




Specifications

Voltage on V_CC, SDA, SCL, and H0-H2 Pins
Relative to Ground.....................................................-0.5V to +6.0V
Voltage on A0, A1, and A2
Relative to Ground .....-0.5V to V_CC ....+ 0.5V, not to exceed +6.0V
Resistor Current ..........................................................  ...........5mA
Operating Temperature Range .................................-40 to +85
EEPROM Programming Temperature Range .................0 to +70
Storage Temperature Range  .................................-55 to +125
Soldering Temperature.........................See J-STD-020 Specification


Description

The DS3906 is intended for low resistance, small step-size applications. It contains three nonvolatile (NV), low-temperature coefficient, variable digital resistors thatare capable of ohm and subohm increments whenused in parallel with a fixed external resistor. All three ofthe DS3906's resistors have 64 positions (plus a high-Zstate) with a pseudo-log response cleverly chosen tohave a linear equivalent resistance when paired with anexternal resistor (see graphs below). The DS3906 alsocontains 16 bytes of user EEPROM that, in addition tothe resistors, are controlled through an I2C™-compati-ble serial interface. Three address pins allow up toeight DS3906s to be placed on the same I2C bus.