Data Sheet
FEATURES
Quad 64-/256-Position I
2
C Nonvolatile
Memory Digital Potentiometers
FUNCTIONAL BLOCK DIAGRAM
V
DD
V
SS
DGND
WP
SCL
SDA
DATA
I
2
C
SERIAL
INTERFACE
RDAC1
REGIS-
TER
RDAC1
A1
W1
B1
RDAC2
RDAC2
REGIS-
TER
A2
W2
B2
RDAC3
RDAC EEMEM
EEMEM
POWER-ON
REFRESH
R
AB
TOL
RDAC0
REGIS-
TER
RDAC0
A0
W0
B0
AD5253: quad 64-position resolution
AD5254: quad 256-position resolution
1 kΩ, 10 kΩ, 50 kΩ, 100 kΩ
Nonvolatile memory
stores wiper settings w/write protection
Power-on refreshed to 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
I
2
C-compatible serial interface
Direct read/write access of RDAC
and EEMEM registers
Predefined linear increment/decrement commands
Predefined ±6 dB step change commands
Synchronous or asynchronous quad-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, T
A
= 55°C
Operating temperature: –40°C to +105°C
CONTROL
COMMAND
DECODE LOGIC
ADDRESS
DECODE LOGIC
CONTROL LOGIC
AD0
AD1
AD5253/AD5254
RDAC3
REGIS-
TER
A3
W3
B3
03824-0-001
Figure 1.
APPLICATIONS
Mechanical potentiometer replacement
Low resolution DAC replacement
RGB LED backlight control
White LED brightness adjustment
RF base station power amp bias control
Programmable gain and offset control
Programmable attenuators
Programmable voltage-to-current conversion
Programmable power supply
Programmable filters
Sensor calibrations
The AD5253/AD5254 allow the host I
2
C 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 AD5253/AD5254 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 AD5253/AD5254 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 AD5253/AD5254 are available in TSSOP-20 packages 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.
1
2
The AD5253/AD5254 are quad-channel, I
2
C®, 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, and extra EEMEM for
storing user-defined information, such as memory data for other
components, look-up table, or system identification information.
Rev. C
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.
GENERAL DESCRIPTION
The terms
nonvolatile memory
and
EEMEM
are used interchangeably.
The terms
digital potentiometer
and
RDAC
are used interchangeably.
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Tel: 781.329.4700 ©2003–2012 Analog Devices, Inc. All rights reserved.
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