Preliminary Technical Data
FEATURES
256-Position One-Time Programmable
Dual-Channel I
2
C Digital Potentiometer
AD5172/AD5173
The AD5172/73 are programmed using a 2-wire I
2
C compatible
digital control. They allow unlimited adjustments before
permanently setting the resistance value. During the OTP
activation, a permanent fuse blown command is sent after the
final value is determined; therefore freezing the wiper position
at a given setting (analogous to placing epoxy on a mechanical
trimmer). Unlike other OTP digital potentiometers in the same
family, AD5172/73 have unique temporary OTP overwriting
feature that new adjustments if desired but the OTP setting is
restored during subsequent power up conditions. To verify the
success of permanent programming, Analog Devices patterned
the OTP validation such that the fuse status can be discerned
from two validation bits in read mode.
For applications that program AD5172/73 in the factories,
Analog Devices offers a device programming software, which
operates across Windows® 95 to XP® platforms including
Windows NT®. This software application effectively replaces the
need for external I
2
C controllers or host processors and
therefore significantly reduces users’ development time.
An AD5172/73 evaluation kit is available, which include the
software, connector, and cable that can be converted for the
factory programming applications.
The AD5172/73 are available in a MSOP-10 package. All parts
are guaranteed to operate over the automotive temperature
range of −40°C to +125°C. Besides their unique OTP features,
the AD5172/73 lend themselves well to other general-purpose
digital potentiometer applications due to their programmable
preset, superior temperature stability, and small form factor.
2-Channel, 256-position
OTP(One-Time Programmable) Set-and-Forget Resistance
Setting — low cost alternative over EEMEM
Unlimited adjustments prior to OTP activation
OTP overwriting function allows temporary adjustments
1
End-to-end resistance 2.5 kΩ, 10 kΩ, 50 kΩ, 100 kΩ
Compact MSOP-10 (3 mm × 4.9 mm) Package
Low tempco 5 ppm/
o
C in potentiometer mode
Low tempco 35 ppm/°C in rheostat mode
Fast Settling Time: t
S
= 5µs Typ in Power-Up
Full read/write of wiper register
Power-on preset to midscale
1
Extra package address decode pins AD0 and AD1(AD5173)
Computer Software Replaces
µC
in Factory Programming
Applications
6 V one-time programming voltage
Single supply 2.7 V to 5.5 V
Low power, I
DD
= 5 µA
Wide operating temperature –40°C to +125°C
APPLICATIONS
Systems Calibrations
Mechanical Potentiometers and Trimmers
®
Replacements
Transducer adjustment
RF amplifier biasing
Automotive electronics adjustment
Gain control and offset adjustment
Electronics Level Settings
FUNCTIONAL BLOCK DIAGRAMS
A1
W1
B1
A2
W2
B2
GENERAL OVERVIEW
The AD5172/73 are dual channel 256-position, one-time
programmable (OTP) digital potentiometers
2
, which employ
fuse link technology to achieve the memory retention of
resistance setting function. OTP is a cost-effective alternative
over the EEMEM approach for users who do not need to
program the digital potentiometer setting in memory for more
than once. These devices perform the same electronic
adjustment functions like most mechanical trimmers and
variable resistors do but offer enhanced resolution, solid-state
reliability, and superior low temperature coefficient
performance.
Rev. PrF 8/14/03
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 companies.
V
DD
GND
1
FUSE
LINKS
2
RDAC
REGISTER 1
RDAC
REGISTER 2
8
SDA
SCL
SERIAL INPUT
REGISTER
Figure 1. AD5172
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
www.analog.com
Tel: 781.329.4700
Fax: 781.326.8703
© 2003 Analog Devices, Inc. All rights reserved.
AD5172/AD5173
W1
B1
W2
B2
Preliminary Technical Data
Figure 2. AD5173
Note:
1. New adjustments are allowed even after OTP is achieved but the
permanent setting will always be restored during subsequent power up
cycles. This feature allows users to use these digital potentiometers as volatile
pots with programmable preset.
2. The terms
digital potentiometer, VR,
and
RDAC
are used interchangeably.
Purchase of licensed I
2
C components of Analog Devices or one of its sublicensed
Associated Companies conveys a license for the purchaser under the Philips I
2
C
Patent Rights to use these components in an I
2
C system, provided that the system
conforms to the I
2
C Standard Specification as defined by Philips.
V
DD
1
FUSE
LINKS
RDAC
REGISTER 1
2
RDAC
REGISTER 2
GND
AD0
AD1
SDA
SCL
ADDRESS
DECODE
8
SERIAL INPUT
REGISTER
Rev. PrF 8/14/03 | Page 2 of 19
Preliminary Technical Data
TABLE OF CONTENTS
Electrical Characteristics—2.5 kΩ Version....................................4
Electrical Characteristics—10 kΩ, 50 kΩ, 100 kΩ Versions ........5
Timing Characteristics—2.5 kΩ, 10 kΩ, 50 kΩ, 100 kΩ Versions
..............................................................................................................6
Absolute Maximum Ratings
1
...........................................................7
Typical Performance Characteristics ..............................................8
Test Circuits .....................................................................................18
I
2
C Interface .......................................................................................8
Operation ...........................................................................................9
Programming the Variable Resistor.......Error!
Bookmark not
defined.
Programming the Potentiometer Divider....Error!
Bookmark
not defined.
I C Compatible 2-Wire Serial Bus ............................................13
Level Shifting for Bidirectional Interface.....Error!
Bookmark
not defined.
2
AD5172/AD5173
ESD Protection .........................Error!
Bookmark not defined.
Terminal Voltage Operating Range .......Error!
Bookmark not
defined.
Power-Up Sequence.................Error!
Bookmark not defined.
POWER supply Considerations.............Error!
Bookmark not
defined.
Layout and Power Supply Bypassing........................................11
Pin Configuration and Function Descriptions ...........................18
Pin Configuration .........................................................................7
Pin Function Descriptions...........................................................7
Outline Dimensions........................................................................19
Ordering Guide ...........................................................................19
ESD Caution ................................................................................19
REVISION HISTORY
Revision Pr F: Initial Version
Rev. PrF 8/14/03 | Page 3 of 19
AD5172/AD5173
ELECTRICAL CHARACTERISTICS—2.5 kΩ VERSION
Preliminary Technical Data
(V
DD
= 5 V ± 10%, or 3 V ± 10%; V
A
= +V
DD
; V
B
= 0 V; –40°C < T
A
< +125°C; unless otherwise noted.)
Table 1.
Parameter
Symbol
Conditions
DC CHARACTERISTICS—RHEOSTAT MODE
Resistor Differential Nonlinearity
2
R-DNL
R
WB
, V
A
= no connect
2
Resistor Integral Nonlinearity
R-INL
R
WB
, V
A
= no connect
Nominal Resistor Tolerance
3
∆R
AB
/R
AB
T
A
= 25°C
Resistance Temperature Coefficient
(∆R
AB
/R
AB
)/∆T V
AB
= V
DD
, Wiper = no connect
Wiper Resistance
R
W
DC CHARACTERISTICS—POTENTIOMETER DIVIDER MODE (Specifications apply to all RDACs)
Resolution
N
4
Differential Nonlinearity
DNL
4
Integral Nonlinearity
INL
Voltage Divider Temperature Coefficient
(∆V
W
/V
W
)/∆T
Code = 0x80
Full-Scale Error
V
WFSE
Code = 0xFF
Zero-Scale Error
V
WZSE
Code = 0x00
RESISTOR TERMINALS
Voltage Range
5
V
A,B,W
Capacitance
6
A, B
C
A,B
f = 1 MHz, measured to GND,
Code = 0x80
6
Capacitance W
C
W
f = 1 MHz, measured to GND,
Code = 0x80
7
Shutdown Supply Current
I
DD_SD
V
DD
= 5.5 V
Common-Mode Leakage
I
CM
V
A
= V
B
= V
DD
/2
DIGITAL INPUTS AND OUTPUTS
Input Logic High
V
IH
Input Logic Low
V
IL
Input Logic High
V
IH
V
DD
= 3 V
Input Logic Low
V
IL
V
DD
= 3 V
Input Current
I
IL
V
IN
= 0 V or 5 V
6
Input Capacitance
C
IL
POWER SUPPLIES
Normal Operating Supply Voltage
V
DD
8
OTP Supply Voltage
V
DD_OTP
T
A
= 25°C
Supply Current
I
DD
V
IH
= 5 V or V
IL
= 0 V
9
OTP Supply Current
I
DD_OTP
V
DD_OTP
=6V, T
A
= 25°C
10
Power Dissipation
P
DISS
V
IH
= 5 V or V
IL
= 0 V, V
DD
= 5 V
Power Supply Sensitivity
PSS
∆V
DD
= +5 V ± 10%,
Code = Midscale
6, 10, 11
DYNAMIC CHARACTERISTICS
Bandwidth –3dB
BW_2.5K
R
AB
= 2.5 kΩ, Code = 0x80
Total Harmonic Distortion
THD
W
V
A
= 1 V rms, V
B
= 0 V, f = 1 kHz
V
W
Settling Time
t
S
V
A
= 5 V, V
B
= 0 V, ±1 LSB error
band, R
WB
= 2.5 kΩ
Resistor Noise Voltage Density
e
N_WB
R
WB
= 2.5 kΩ, RS = 0
Min
–1.5
–4
–30
Typ
1
±0.1
±0.75
35
50
Max
+1.5
+4
+30
120
8
+1.5
+1.5
0
+6
V
DD
45
60
0.01
1
2.4
0.8
2.1
0.6
±1
5
2.7
3
100
±0.02
0.2
±0.05
5.5
5
1
Unit
LSB
LSB
%
ppm/°C
Ω
Bits
LSB
LSB
ppm/°C
LSB
LSB
V
pF
pF
µA
nA
V
V
V
V
µA
pF
V
µA
mA
mW
%/%
–1.5
–1.5
–6
0
GND
±0.1
±0.6
15
–2.5
+2
2.4
0.05
1
4.5
MHz
%
µs
nV/√Hz
Rev. PrF 8/14/03 | Page 4 of 19
Preliminary Technical Data
ELECTRICAL CHARACTERISTICS—10 kΩ, 50 kΩ, 100 kΩ VERSIONS
(V
DD
= 5 V ± 10%, or 3 V ± 10%; V
A
= V
DD
; V
B
= 0 V; –40°C < T
A
< +125°C; unless otherwise noted.)
Table 2.
Parameter
DC CHARACTERISTICS—RHEOSTAT MODE
Resistor Differential Nonlinearity
2
Resistor Integral Nonlinearity
2
Nominal Resistor Tolerance
3
Resistance Temperature Coefficient
Symbol
R-DNL
R-INL
∆R
AB
/R
AB
(∆R
AB
/R
AB
)/∆T
Conditions
Min
–1
–2
–30
Typ
1
±0.1
±0.25
35
50
AD5172/AD5173
Max
+1
+2
+30
Unit
LSB
LSB
%
ppm/°C
Ω
Bits
LSB
LSB
ppm/°C
LSB
LSB
V
pF
pF
R
WB
, A = no connect
R
WB
, A = no connect
T
A
= 25°C
V
AB
= V
DD
,
Wiper = no connect
Wiper Resistance
R
W
V
DD
= 5 V
DC CHARACTERISTICS—POTENTIOMETER DIVIDER MODE (Specifications apply to all VRs)
Resolution
N
4
Differential Nonlinearity
DNL
R
WB
, A = no connect
Integral Nonlinearity
4
INL
R
WB
, A = no connect
Voltage Divider Temperature Coefficient
(∆V
W
/V
W
)/∆T
Code = 0x80
Full-Scale Error
V
WFSE
Code = 0xFF
Zero-Scale Error
V
WZSE
Code = 0x00
RESISTOR TERMINALS
Voltage Range
5
V
A,B,W
6
Capacitance A, B
C
A,B
f = 1 MHz, measured to
GND, Code = 0x80
6
Capacitance W
C
W
f = 1 MHz, measured to
GND, Code = 0x80
7
Shutdown Supply Current
I
DD_SD
V
DD
= 5.5 V
Common-Mode Leakage
I
CM
V
A
= V
B
= V
DD
/2
DIGITAL INPUTS AND OUTPUTS
Input Logic High
V
IH
Input Logic Low
V
IL
Input Logic High
V
IH
V
DD
= 3 V
Input Logic Low
V
IL
V
DD
= 3 V
Input Current
I
IL
V
IN
= 0 V or 5 V
6
Input Capacitance
C
IL
POWER SUPPLIES
Normal Operating Supply Voltage
V
DD
OTP Supply Voltage
8
V
DD_OTP
T
A
= 25°C
Supply Current
I
DD
V
IH
= 5 V or V
IL
= 0 V
9
OTP Supply Current
I
DD_OTP
V
DD_OTP
=6V, T
A
= 25°C
10
Power Dissipation
P
DISS
V
IH
= 5 V or V
IL
= 0 V,
V
DD
= 5 V
Power Supply Sensitivity
PSS
∆V
DD
= +5 V ± 10%,
Code = Midscale
6, 10, 11
DYNAMIC CHARACTERISTICS
Bandwidth –3dB
BW
R
AB
= 10 kΩ/50 kΩ/100 kΩ,
Code = 0x80
Total Harmonic Distortion
THD
W
V
A
=1 V rms, V
B
= 0 V,
f = 1 kHz, R
AB
= 10 kΩ
V
W
Settling Time (10 kΩ/50 kΩ/100 kΩ)
t
S
V
A
= 5 V, V
B
= 0 V, ±1 LSB
error band, R
WB
= 5 kΩ
Resistor Noise Voltage Density
e
N_WB
R
WB
= 5 kΩ, RS = 0
120
8
+1
+1
0
+3
V
DD
–1
–1
–3
0
GND
±0.1
±0.3
15
–1
+1
45
60
0.01
1
2.4
0.8
2.1
0.6
±1
5
2.7
6
3
100
0.2
±0.02
±0.05
5.5
6.5
5
1
µA
nA
V
V
V
V
µA
pF
V
V
µA
mA
mW
%/%
600/100/40
0.05
2
9
kHz
%
µs
nV/√Hz
Rev. PrF 8/14/03 | Page 5 of 19