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Data Sheet
Dual 64-/256-Position I2C Nonvolatile
Memory Digital Potentiometers
AD5251/AD5252
FEATURES
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
APPLICATIONS
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
Sensor calibrations
GENERAL DESCRIPTION
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,
VDD
VSS
DGND
WP
SCL
SDA
AD0
AD1
FUNCTIONAL BLOCK DIAGRAM
I2C
SERIAL
INTERFACE
POWER-
ON RESET
RDAC EEMEM
EEMEM
POWER-ON
REFRESH
RAB
TOL
RDAC1
REGIS-
TER
RDAC1
DATA
CONTROL
RDAC3
REGIS-
TER
RDAC3
COMMAND
DECODE LOGIC
ADDRESS
DECODE LOGIC
CONTROL LOGIC
AD5251/
AD5252
A1
W1
B1
A3
W3
B3
Figure 1.
and extra EEMEM for storing user-defined information, such as
memory data for other components, look-up table, or system
identification information.
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.
Rev. E
Document Feedback
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.
Trademarksandregisteredtrademarksarethepropertyoftheirrespectiveowners.
1 The terms nonvolatile memory and EEMEM are used interchangeably.
2 The terms digital potentiometer and RDAC are used interchangeably.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 ©2004–2017 Analog Devices, Inc. All rights reserved.
Technical Support
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AD5251/AD5252
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Electrical Characteristics ................................................................. 3
1 kΩ Version.................................................................................. 3
10 kΩ, 50 kΩ, 100 kΩ Versions .................................................. 5
Interface Timing Characteristics ................................................ 7
Absolute Maximum Ratings............................................................ 8
ESD Caution.................................................................................. 8
Pin Configuration and Function Descriptions............................. 9
Typical Performance Characteristics ........................................... 10
I2C Interface..................................................................................... 14
I2C Interface General Description............................................ 14
I2C Interface Detail Description ............................................... 15
I2C-Compatible 2-Wire Serial Bus ........................................... 20
REVISION HISTORY
11/2017—Rev. D to Rev. E
Changes to Features Section and General Description Section........ 1
Changes to Theory of Operation Section.................................... 21
Changes to Ordering Guide .......................................................... 27
9/2012—Rev. C to Rev. D
Changed Temperature Range from –40°C to +85°C to –40°C to
+105°C (Throughout) ...................................................................... 1
Changed
WPE
A
Leakage
Current
from
5
µA
to
8
µA,
Table
1........
4
Changed
WPE
AA
Leakage
Current
from
5
µA
to
8
µA,
Table
2........
5
Changes to Figure 11 and Figure 12............................................. 11
12/2011—Rev. B to Rev. C
Changes to Theory of Operation Section.................................... 21
Changes to Ordering Guide .......................................................... 27
10/2009—Rev. A to Rev. B
Changes to Figure 15...................................................................... 12
Changes to Figure 27...................................................................... 15
Data Sheet
Theory of Operation ...................................................................... 21
Linear Increment/Decrement Commands ............................. 21
±6 dB Adjustments (Doubling/Halving Wiper Setting) ....... 21
Digital Input/Output Configuration........................................ 21
Multiple Devices on One Bus ................................................... 22
Terminal Voltage Operation Range ......................................... 22
Power-Up and Power-Down Sequences.................................. 22
Layout and Power Supply Biasing ............................................ 23
Digital Potentiometer Operation ............................................. 23
Programmable Rheostat Operation......................................... 23
Programmable Potentiometer Operation ............................... 24
Applications Information .............................................................. 25
LCD Panel VCOM Adjustment.................................................... 25
Current-Sensing Amplifier ....................................................... 25
Adjustable High Power LED Driver ........................................ 25
Outline Dimensions ....................................................................... 26
Ordering Guide .......................................................................... 27
9/2005—Rev. 0 to Rev. A
Updated Format..................................................................Universal
Change to Figure 6 ......................................................................... 10
Changes to Figure 28...................................................................... 15
Changes to Figure 29...................................................................... 17
Changes to RDAC/EEMEM Quick Commands Section .......... 18
Changes to EEMEM Write Protection Section .......................... 18
Changes to Figure 37...................................................................... 22
Deleted Table 13 and Table 14 ...................................................... 23
Change to Figure 42 ....................................................................... 24
Change to Figure 46 ....................................................................... 25
Changes to Ordering Guide .......................................................... 27
6/2004—Revision 0: Initial Version
Rev. E | Page 2 of 28

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Data Sheet
AD5251/AD5252
ELECTRICAL CHARACTERISTICS
1 kΩ VERSION
VDD = 3 V ± 10% or 5 V ± 10%, VSS = 0 V or VDD/VSS = ±2.5 V ± 10%, VA = VDD, VB = 0 V, –40°C < TA < +105°C, unless otherwise noted.
Table 1.
Parameter
DC CHARACTERISTICS—
RHEOSTAT MODE
Resolution
Resistor Differential Nonlinearity2
3F3F
Resistor Nonlinearity2
Nominal Resistor Tolerance
Resistance Temperature
Coefficient
Wiper Resistance
Channel-Resistance Matching
DC CHARACTERISTICS—
POTENTIOMETER DIVIDER MODE
Differential Nonlinearity3
4F
Integral Nonlinearity3
Voltage Divider Tempco
Full-Scale Error
Zero-Scale Error
RESISTOR TERMINALS
Voltage Range4
5F
Capacitance5 A, B
6F
Capacitance5 W
Common-Mode Leakage Current
Symbol
Conditions
N
R-DNL
R-INL
ΔRAB/RAB
(ΔRAB/RAB) × 106/ΔT
AD5251
AD5252
RWB, RWA = NC, VDD = 5.5 V, AD5251
RWB, RWA = NC, VDD = 5.5 V, AD5252
RWB, RWA = NC, VDD = 2.7 V, AD5251
RWB, RWA = NC, VDD = 2.7 V, AD5252
RWB, RWA = NC, VDD = 5.5 V, AD5251
RWB, RWA = NC, VDD = 5.5 V, AD5252
RWB, RWA = NC, VDD = 2.7 V, AD5251
RWB, RWA = NC, VDD = 2.7 V, AD5252
TA = 25°C
RW
ΔRAB1/ΔRAB3
IW = 1 V/R, VDD = 5 V
IW = 1 V/R, VDD = 3 V
DNL
INL
(ΔVW/VW) × 106/ΔT
VWFSE
VWZSE
AD5251
AD5252
AD5251
AD5252
Code = half scale
Code = full scale, VDD = 5.5 V,
AD5251
Code = full scale, VDD = 5.5 V,
AD5252
Code = full scale, VDD = 2.7 V,
AD5251
Code = full scale, VDD = 2.7 V,
AD5252
Code = zero scale, VDD = 5.5 V,
AD5251
Code = zero scale, VDD = 5.5 V,
AD5252
Code = zero scale, VDD = 2.7 V,
AD5251
Code = zero scale, VDD = 2.7 V,
AD5252
VA, VB, VW
CA, CB
CW
ICM
f = 1 kHz, measured to GND,
code = half scale
f = 1 kHz, measured to GND,
code = half scale
VA = VB = VDD/2
Min
–0.5
–1.00
–0.75
–1.5
–0.5
–2.0
–1.0
–2
–30
–0.5
–1.00
–0.5
–2.0
–5
–16
−6
–23
0
0
0
0
VSS
Typ 1
2F2F
±0.2
±0.25
±0.30
±0.3
±0.2
±0.5
+2.5
+9
650
75
200
0.15
±0.1
±0.25
±0.2
±0.5
25
–3
–11
–4
–16
3
11
4
15
85
95
0.01
Max
6
8
+0.5
+1.00
+0.75
+1.5
+0.5
+2.0
+4.0
+14
+30
130
300
+0.5
+1.00
+0.5
+2.0
0
0
0
0
5
16
6
20
VDD
1
Unit
Bits
Bits
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
%
ppm/°C
%
LSB
LSB
LSB
LSB
ppm/°C
LSB
LSB
LSB
LSB
LSB
LSB
LSB
LSB
V
pF
pF
µA
Rev. E | Page 3 of 28

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AD5251/AD5252
Data Sheet
Parameter
DIGITAL INPUTS AND OUTPUTS
Input Logic High
Input Logic Low
Output Logic High (SDA)
Output Logic Low (SDA)
WP Leakage Current
A EA
A0 Leakage Current
Input Leakage Current
(Other than WPE and A0)
AA
Input Capacitance5
POWER SUPPLIES
Single-Supply Power Range
Dual-Supply Power Range
Positive Supply Current
Negative Supply Current
EEMEM Data Storing Mode
Current
EEMEM Data Restoring Mode
Current6
7F
Power Dissipation7
8F
Power Supply Sensitivity
DYNAMIC CHARACTERISTICS5, 8
9F
Bandwidth –3 dB
Total Harmonic Distortion
VW Settling Time
Resistor Noise Voltage
Digital Crosstalk
Analog Coupling
Symbol
VIH
VIL
VOH
VOL
IWP
IA0
II
CI
VDD
VDD/VSS
IDD
ISS
IDD_STORE
IDD_RESTORE
PDISS
PSS
BW
THD
tS
eN_WB
CT
CAT
Conditions
Min
Typ 1
2F2F
Max
Unit
VDD = 5 V, VSS = 0 V
VDD/VSS = 2.7 V/0 V or VDD/VSS = ± 2.5
V
VDD = 5 V, VSS = 0 V
RPULL-UP = 2.2 kΩ to VDD = 5 V, VSS = 0
V
RPULL-UP = 2.2 kΩ to VDD = 5 V, VSS = 0
V
WP = VDDA E A
A0 = GND
VIN = 0 V or VDD
2.4
2.1
4.9
5
V
V
0.8 V
V
0.4 V
8 µA
3 µA
±1 µA
pF
VSS = 0 V
VIH = VDD or VIL = GND
VIH = VDD or VIL = GND, VDD = 2.5 V,
VSS = –2.5 V
VIH = VDD or VIL = GND
VIH = VDD or VIL = GND
VIH = VDD = 5 V or VIL = GND
ΔVDD = 5 V ± 10%
ΔVDD = 3 V ± 10%
2.7
±2.25
5
–5
5.5
±2.75
15
–15
V
V
µA
µA
35 mA
2.5 mA
−0.025
–0.04
+0.010
+0.02
0.075
+0.025
+0.04
mW
%/%
%/%
RAB = 1 kΩ
VA = 1 V rms, VB = 0 V, f = 1 kHz
VA = VDD, VB = 0 V
RWB = 500 Ω, f = 1 kHz
(thermal noise only)
VA = VDD, VB = 0 V, measure VW with
adjacent RDAC making full-scale
change
Signal input at A1 and measure
the output at W3, f = 1 kHz
4
0.05
0.2
3
–80
–72
MHz
%
µs
nV/√HzE
A
dB
dB
1 Typical values represent average readings at 25°C and VDD = 5 V.
2 Resistor position nonlinearity error (R-INL) is the deviation from an ideal value measured between the maximum and minimum resistance wiper positions. R-DNL is the
relative step change from an ideal value measured between successive tap positions. Parts are guaranteed monotonic, except R-DNL of AD5252 1 kΩ version at VDD =
2.7 V, IW = VDD/R for both VDD = 3 V and VDD = 5 V.
3 INL and DNL are measured at VW with the RDAC configured as a potentiometer divider, similar to a voltage output digital-to-analog converter. VA = VDD and VB = 0 V.
DNL specification limits of ±1 LSB maximum are guaranteed monotonic operating conditions.
4 Resistor Terminal A, Terminal B, and Terminal W have no limitations on polarity with respect to each other.
5 Guaranteed by design and not subject to production test.
6 Command 0 NOP should be activated after Command 1 to minimize IDD_READ current consumption.
7 PDISS is calculated from IDD × VDD = 5 V.
8 All dynamic characteristics use VDD = 5 V.
Rev. E | Page 4 of 28

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Data Sheet
AD5251/AD5252
10 kΩ, 50 kΩ, 100 kΩ VERSIONS
VDD = +3 V ± 10% or +5 V ± 10%, VSS = 0 V or VDD/VSS = ± 2.5 V ± 10%, VA = VDD, VB = 0 V, –40°C < TA < +105°C, unless otherwise noted.
Table 2.
Parameter
DC CHARACTERISTICS—
RHEOSTAT MODE
Resolution
Resistor Differential Nonlinearity2
1F
Resistor Nonlinearity2
Nominal Resistor Tolerance
Resistance Temperature
Coefficient
Wiper Resistance
Channel-Resistance Matching
DC CHARACTERISTICS—
POTENTIOMETER DIVIDER MODE
Differential Nonlinearity3
12F
Integral Nonlinearity3
Voltage Divider
Temperature Coefficient
Full-Scale Error
Zero-Scale Error
RESISTOR TERMINALS
Voltage Range4
13F
Capacitance5 A, B
14F
Capacitance5 W
Common-Mode Leakage Current
DIGITAL INPUTS AND OUTPUTS
Input Logic High
Input Logic Low
Output Logic High (SDA)
Output Logic Low (SDA)
WP Leakage Current
A EA
A0 Leakage Current
Input Leakage Current
(Other than WPE and A0)
AA
Input Capacitance5
Symbol
N
R-DNL
R-INL
ΔRAB/RAB
(ΔRAB/RAB) × 106/ΔT
RW
ΔRAB1/ΔRAB2
DNL
INL
(ΔVW/VW) × 106/ΔT
VWFSE
VWZSE
VA, VB, VW
CA, CB
CW
ICM
VIH
VIL
VOH
VOL
IWP
IA0
II
CI
Conditions
AD5251
AD5252
RWB, RWA = NC, AD5251
RWB, RWA = NC, AD5252
RWB, RWA = NC, AD5251
RWB, RWA = NC, AD5252
TA = 25°C
IW = 1 V/R, VDD = 5 V
IW = 1 V/R, VDD = 3 V
RAB = 10 kΩ, 50 kΩ
RAB = 100 kΩ
AD5251
AD5252
AD5251
AD5252
Code = half scale
Code = full scale, AD5251
Code = full scale, AD5252
Code = zero scale, AD5251
Code = zero scale, AD5252
f = 1 kHz, measured to GND,
code = half scale
f = 1 kHz, measured to GND,
code = half scale
VA = VB = VDD/2
VDD = 5 V, VSS = 0 V
VDD/VSS = +2.7 V/0 V or VDD/VSS = ±2.5 V
VDD = 5 V, VSS = 0 V
VDD/VSS = +2.7 V/0 V or VDD/VSS = ±2.5 V
RPULL-UP = 2.2 kΩ to VDD = 5 V, VSS = 0 V
RPULL-UP = 2.2 kΩ to VDD = 5 V, VSS = 0 V
WP = VE
AA
DD
A0 = GND
VIN = 0 V or VDD
Min
−0.75
−1.00
−0.75
−2.5
−20
−0.5
−1.0
−0.50
−1.5
−1.0
−3
0
0
VSS
2.4
2.1
4.9
Typ 1
10F
±0.10
±0.25
±0.25
±1.0
650
75
200
0.15
0.05
±0.1
±0.3
±0.15
±0.5
15
−0.3
−1
0.3
1.2
85
95
0.01
5
Max Unit
6
8
+0.75
+1.00
+0.75
+2.5
+20
Bits
Bits
LSB
LSB
LSB
LSB
%
ppm/°C
130 Ω
300 Ω
%
%
+0.5
+1.0
+0.50
+1.5
LSB
LSB
LSB
LSB
ppm/°C
0 LSB
0 LSB
1.0 LSB
3.0 LSB
VDD V
pF
pF
1.00 µA
V
V
0.8 V
0.6 V
V
0.4 V
8 µA
3 µA
±1 µA
pF
Rev. E | Page 5 of 28