Dual 64-/256-Position I2C Nonvolatile
Memory Digital Potentiometers
AD5251: Dual 64-position resolution
AD5252: Dual 256-position resolution
AD5251: 50 kΩ
AD5252: 1 kΩ, 10 kΩ, 50 kΩ, 100 kΩ
Nonvolatile memory1 stores wiper setting w/write protection
Power-on refreshed with EEMEM settings in 300 µs typ
EEMEM rewrite time = 540 µs typ
Resistance tolerance stored in nonvolatile memory
12 extra bytes in EEMEM for user-defined information
I2C-compatible serial interface
Direct read/write access of RDAC2 and EEMEM registers
Predefined linear increment/decrement commands
Predefined ±6 dB step change commands
Synchronous or asynchronous dual-channel update
Wiper setting readback
4 MHz bandwidth—1 kΩ version
Single supply 2.7 V to 5.5 V
Dual supply ±2.25 V to ±2.75 V
2 slave address decoding bits allow operation of 4 devices
100-year typical data retention, TA = 55°C
Operating temperature: –40°C to +105°C
Mechanical potentiometer replacement
General-purpose DAC replacement
LCD panel VCOM adjustment
White LED brightness adjustment
RF base station power amp bias control
Programmable gain and offset control
Programmable voltage-to-current conversion
Programmable power supply
The AD5251/AD5252 are dual-channel, I2C®, nonvolatile mem-
ory, digitally controlled potentiometers with 64/256 positions,
respectively. These devices perform the same electronic adjust-
ment functions as mechanical potentiometers, trimmers, and
variable resistors. The parts’ versatile programmability allows
multiple modes of operation, including read/write access in the
RDAC and EEMEM registers, increment/decrement of resistance,
resistance changes in ±6 dB scales, wiper setting readback,
FUNCTIONAL BLOCK DIAGRAM
and extra EEMEM for storing user-defined information, such as
memory data for other components, look-up table, or system
The AD5251/AD5252 allow the host I2C controllers to write
any of the 64-/256-step wiper settings in the RDAC registers
and store them in the EEMEM. Once the settings are stored,
they are restored automatically to the RDAC registers at system
power-on; the settings can also be restored dynamically.
The AD5251/AD5252 provide additional increment,
decrement, +6 dB step change, and –6 dB step change in
synchronous or asynchronous channel update mode. The
increment and decrement functions allow stepwise linear
adjustments, with a ± 6 dB step change equivalent to doubling
or halving the RDAC wiper setting. These functions are useful
for steep-slope, nonlinear adjustments, such as white LED
brightness and audio volume control.
The AD5251/AD5252 have a patented resistance-tolerance
storing function that allows the user to access the EEMEM and
obtain the absolute end-to-end resistance values of the RDACs
for precision applications.
The AD5251/AD5252 are available in TSSOP-14 packages.
AD5251 has only 50 kΩ resistance options and AD5252 is
available in 1 kΩ, 10 kΩ, 50 kΩ, and 100 kΩ options. All parts
are guaranteed to operate over the –40°C to +105°C extended
industrial temperature range.
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibilityisassumedbyAnalogDevices for itsuse,nor foranyinfringementsofpatentsor other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
1 The terms nonvolatile memory and EEMEM are used interchangeably.
2 The terms digital potentiometer and RDAC are used interchangeably.
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