Triple NV Low Step Size Variable Resistor Plus Memory

General Description
The DS3906 is intended for low resistance, small step-size applications. It contains three nonvolatile (NV), low-temperature coefficient, variable digital resistors that are capable of ohm and subohm increments when used in parallel with a fixed external resistor. All three of the DS3906 s resistors have 64 positions (plus a high-Z state) with a pseudo-log response cleverly chosen to have a linear equivalent resistance when paired with an external resistor (see graphs below). The DS3906 also contains 16 bytes of user EEPROM that, in addition to the resistors, are controlled through an l2C-compatible serial interface. Three address pins allow up to eight DS3906s to be placed on the same l2C bus.