WMS7170 / 7171
1. GENERAL DESCRIPTION
The WMS7170/7171 is a single channel 100-tap non-volatile linear digital potentiometer available in
10KΩ, 50KΩ and 100KΩ resistance. The device consists of Up/Down serial interface, tap register,
decoder, resistor array, wiper switches, NV memory and control logics.
The WMS7170 device can be configured as a two-terminal variable resistor or a three-terminal voltage
divider without an output buffer, but the WMS7171 device, which has a built-in output buffer, can only
be configured as a three-terminal voltage divider. Both devices can be used in a wide variety of
applications.
The output of the potentiometer is determined by its wiper position, which varies linearly between its
end terminals, RA/VA and RB/VB. The wiper position, Rw/Vw, is controlled by Up/Down serial interface
( CS , INC and U/ D ) through the Tap Register (TR). In addition, the wiper position can also be
stored into a non-volatile memory location (NVMEM0), which is then automatically recalled upon
power up.
2. FEATURES
• Drop-in replacement for many popular parts
• Single linear-taper channel
• 100 taps
• 10K, 50K and 100K end-to-end resistance
• VSS to VDD terminal voltages
• Automatic recall of wiper position when power-on
• Potentiometer control through Up/Down (3-wire) serial interface
• Endurance 100,000 cycles
• Data retention 100 years
• Package options:
- 8-pin PDIP, SOIC or MSOP
• Industrial temperature range: -40° to 85°C
• Single supply operation : 2.7V to 5.5V
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