3-Channel Digital Potentiometer with
25 kΩ or 250 kΩ full-scale resistance
Low temperature coefficient:
Potentiometer divider 15 ppm/°C
Rheostat mode 35 ppm/°C
Nonvolatile memory retains wiper settings
Permanent memory write protection
±6 dB increment/decrement
I2C-compatible serial interface
2.7 V to 5.5 V single-supply operation
±2.25 V to ±2.75 V dual-supply operation
Power-on reset time
256 bytes general-purpose user EEPROM
11 bytes RDAC user EEPROM
GBIC and SFP compliant EEPROM
100-year typical data retention at TA = 55°C
Mechanical potentiometer replacement
RGB LED backlight control
White LED brightness adjustment
Programmable gain and offset control
The AD5255 provides dual 512-position and a single
128-position digitally controlled variable resistors1 (VR) in a
TSSOP package. This device performs the same electronic
adjustment function as a potentiometer, trimmer, or variable
resistor. Each VR offers a completely programmable value of
resistance between the A terminal and the wiper or the B
terminal and the wiper. The fixed A-to-B terminal resistance of
25 kΩ or 250 kΩ has a 1% channel-to-channel matching
tolerance and a nominal temperature coefficient of 35 ppm/°C.
Wiper position programming, EEPROM2 reading, and EEPROM
writing is conducted via the standard 2-wire I2C interface. Pre-
vious/default wiper position settings can be stored in memory,
and refreshed upon system power-up.
FUNCTIONAL BLOCK DIAGRAM
Additional features of the AD5255 include preprogrammed
linear and logarithmic increment/decrement wiper changing.
The actual resistor tolerances are stored in EEPROM so that the
actual end-to-end resistance is known, which is valuable for
calibration in precision applications.
The AD5255 is available in a 24-lead TSSOP package. All parts
are guaranteed to operate over the extended industrial tempera-
ture range of −40°C to +85°C.
1 The terms programmable resistor, variable resistor, RDAC, and digital
potentiometer are used interchangeably.
2 The terms nonvolatile memory, EEMEM, and EEPROM are used
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or 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. Trademarks and
registered trademarks are the property of their respective owners.
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Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.