WMS7202
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1. GENERAL DESCRIPTION
The WMS7202 is a 256-tap, dual-channel non-volatile digital potentiometer available in 10KΩ, 50KΩ
and 100KΩ end-to-end resistances. These devices can be used as a three-terminal potentiometer or
as a two terminal variable resistor in a wide variety of applications.
The output of each potentiometer is determined by the wiper position, which varies linearly between
VA and VB terminal according to the content stored in the volatile Tap Register (TR). The settings of
the TR can be provided either directly by the user through the industry standard SPI interface, or by
the non-volatile memory (NVMEM0~3) where the previous settings are stored. When changes are
made to the TR to establish a new wiper position, the value of the setting can be saved into any non-
volatile memory location (NVMEM0~3) by executing a NVMEM save operation. Each channel has its
own four non-volatile memory locations (NVMEM0~3) that can be directly written to, and read by,
users through the SPI interface. Upon powerup the content of the NVMEM0 is automatically loaded to
the Tap Register.
The WMS7202 contains two independent channels in 14-pin PDIP, SOIC and TSSOP packages and
can operate over a wide operating voltage range from 2.7V to 5.5V. A selectable output buffer is built-
in for each channel for those applications where an output buffer is required.
2. FEATURES
• 256 taps for each potentiometer
• Dual independent, linear-taper channels in one package
• End-to-end resistance available in 10KΩ, 50KΩ and 100KΩ
• Selectable output buffer for each channel
• SPI Serial Interface for data transfer and potentiometer control
• Daisy-chain operation for multiple devices
• Nonvolatile storage of four wiper positions per channel with power-on recall from NVMEM0
• Low standby current (1µA Max. with output buffer inactive)
• Endurance 100K typical stores per bit
• Register Data Retention 100 years
• Industrial temperature range: -40 ~ 85°C
• Wide operating voltage range: 2.7V ~ 5.5V
• Package option:
14-pin TSSOP, 14-pin SOIC, 14-pin PDIP
