ANALOG DEVICES AD5162 Service Manual
Dual 256-Position SPI
A
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FEATURES
2-channel, 256-position
End-to-end resistance: 2.5 kΩ, 10 kΩ, 50 kΩ, 100 kΩ
Compact MSOP-10 (3 mm × 4.9 mm) package
Fast settling time: t
Full read/write of wiper register
Power-on preset to midscale
Extra package address decode pin AD0
Computer software replaces µC in factory programming
applications
Single supply: 2.7 V to 5.5 V
Low temperature coefficient: 35 ppm/°C
Low power: I
Wide operating temperature: −40°C to +125°C
Evaluation board available
APPLICATIONS
Systems calibrations
Electronics level settings
Mechanical Trimmers® replacement in new designs
Permanent factory PCB setting
Transducer adjustment of pressure, temperature, position,
chemical, and optical sensors
RF amplifier biasing
Automotive electronics adjustment
Gain control and offset adjustment
GENERAL DESCRIPTION
The AD5162 provides a compact 3 mm × 4.9 mm packaged
solution for dual 256-position adjustment applications. This
device performs the same electronic adjustment function as a
3-terminal mechanical potentiometer. Available in four different
end-to-end resistance values (2.5 kΩ, 10 kΩ, 50 kΩ, 100 kΩ),
this low temperature coefficient device is ideal for high accuracy and stability variable resistance adjustments. The wiper
settings are controllable through an SPI digital interface. The
resistance between the wiper and either endpoint of the fixed
resistor varies linearly with respect to the digital code
transferred into the RDAC
1
The terms digital potentiometer, VR, and RDAC are used interchangeably.
= 5 µs typical on power-up
S
= 6 µA max
DD
1
latch.
Digital Potentiometer
AD5162
FUNCTIONAL BLOCK DIAGRAM
1
V
DD
GND
CLK
SDI
CS
REGISTER 1
A = 0 A = 1
Operating from a 2.7 V to 5.5 V power supply and consuming
less than 6 µA allows the AD5162 to be used in portable
battery-operated applications.
For applications that program the AD5162 at the factory,
Analog Devices offers device programming software running
on Windows® NT/2000/XP operating systems. This software
effectively replaces any external SPI controllers, which in turn
enhances users’ systems time-to-market. An AD5162 evaluation
kit and software are available. The kit includes a cable and
instruction manual.
W1
WIPER
SPI INTERFACE
B1 W2
WIPER
REGISTER 2
Figure 1.
B2
AD5162
04108-0-001
Rev. A
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 www.analog.com
Fax: 781.326.8703 © 2003 Analog Devices, Inc. All rights reserved.
AD5162
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TABLE OF CONTENTS
Electrical Characteristics—2.5 kΩ Version................................... 3
Programming the Potentiometer Divider............................... 14
Electrical Characteristics—10 kΩ, 50 kΩ, 100 kΩ Versions ....... 4
Timing Characteristics—All Versions ........................................... 5
Absolute Maximum Ratings............................................................ 6
ESD Caution.................................................................................. 6
Pin Configuration and Function Descriptions............................. 7
Pin Configuration......................................................................... 7
Pin Function Descriptions .......................................................... 7
Typical Performance Characteristics ............................................. 8
Tes t Ci rc u it s ..................................................................................... 12
Theory of Operation ...................................................................... 13
Pro g ram m ing t he Vari a bl e Re s ist o r a n d Vol ta g e .................... 13
REVISION HISTORY
11/03 Changed from REV. 0 to REV. A:
Changes to Electrical Characteristics.................................... Page 3
ESD Protection ........................................................................... 14
Terminal Voltage Operating Range.......................................... 14
Power-Up Sequence ................................................................... 14
Layout and Power Supply Bypassing ....................................... 15
Constant Bias to Retain Resistance Setting............................. 15
Evaluation Board ........................................................................ 15
SPI Interface .................................................................................... 16
SPI Compatible 3-Wire Serial Bus ........................................... 16
Outline Dimensions....................................................................... 17
Ordering Guide .......................................................................... 17
11/03 Revision 0: Initial Version
Rev. A | Page 2 of 20
AD5162
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ELECTRICAL CHARACTERISTICS—2.5 kΩ VERSION
Table 1. VDD = 5 V ± 10%, or 3 V ± 10%; VA = +VDD; VB = 0 V; −40°C < TA < +125°C; unless otherwise noted
Parameter Symbol Conditions Min Typ
DC CHARACTERISTICS—RHEOSTAT MODE
Resistor Differential Nonlinearity
Resistor Integral Nonlinearity
Nominal Resistor Tolerance
2
2
3
R-DNL RWB, VA = no connect −2 ±0.1 +2 LSB
R-INL RWB, VA = no connect −6 ±0.75 +6 LSB
∆R
AB
TA = 25°C −20 +55 %
Resistance Temperature Coefficient (∆RAB/RAB )/∆T VAB = VDD, wiper = no connect 35 ppm/°C
R
(Wiper Resistance) R
WB
WB
Code = 0x00, VDD = 5 V 160 200 Ω
DC CHARACTERISTICS—POTENTIOMETER DIVIDER MODE (Specifications Apply to All VRs)
Differential Nonlinearity
4
DNL −1.5 ±0.1 +1.5 LSB
Integral Nonlinearity INL −2 ±0.6 +2 LSB
Voltage Divider Temperature
(∆V
)/∆T Code = 0x80 15 ppm/°C
W/VW
Coefficient
Full-Scale Error V
Zero-Scale Error V
WFSE
WZSE
Code = 0xFF −10 −2.5 0 LSB
Code = 0x00 0 2 10 LSB
RESISTOR TERMINALS
Voltage Range
Capacitance6 A, B C
5
V
A, B, W
A, B
GND V
f = 1 MHz, measured to GND, Code =
45 pF
0x80
Capacitance6 W C
W
f = 1 MHz, measured to GND, Code =
60 pF
0x80
Common-Mode Leakage I
CM
VA = VB = VDD/2 1 nA
DIGITAL INPUTS AND OUTPUTS
Input Logic High V
Input Logic Low V
Input Logic High V
Input Logic Low V
Input Current I
Input Capacitance
6
IH
IL
IH
IL
IL
C
IL
VDD = 5 V 2.4 V
VDD = 5 V 0.8 V
VDD = 3 V 2.1 V
VDD = 3 V 0.6 V
VIN = 0 V or 5 V ±1 µA
5 pF
POWER SUPPLIES
Power Supply Range V
Supply Current I
Power Dissipation
7
DD RANGE
DD
P
DISS
2.7 5.5 V
VIH = 5 V or VIL = 0 V 3.5 6 µA
VIH = 5 V or VIL = 0 V, VDD = 5 V 30 µW
Power Supply Sensitivity PSS VDD = 5 V ± 10%, Code = midscale ±0.02 ±0.08 %/%
DYNAMIC CHARACTERISTICS
8
Bandwidth −3 dB BW_2.5 K Code = 0x80 4.8 MHz
Total Harmonic Distortion THD
VW Settling Time t
Resistor Noise Voltage Density e
See notes at end of section.
W
S
N_WB
VA = 1 V rms, VB = 0 V, f = 1 kHz 0.1 %
VA = 5 V, VB = 0 V, ±1 LSB error band 1 µs
RWB = 1.25 kΩ, RS = 0 3.2
1
Max Unit
DD
V
nV/√Hz
Rev. A | Page 3 of 20
AD5162
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ELECTRICAL CHARACTERISTICS—10 kΩ, 50 kΩ, 100 kΩ VERSIONS
Table 2. VDD = 5 V ± 10%, or 3 V ± 10%; VA = VDD; VB = 0 V; −40°C < TA < 125°C; unless otherwise noted
Parameter Symbol Conditions Min Typ
DC CHARACTERISTICS—RHEOSTAT MODE
Resistor Differential Nonlinearity
Resistor Integral Nonlinearity
Nominal Resistor Tolerance
2
2
3
R-DNL RWB, VA = no connect −1 ±0.1 +1 LSB
R-INL RWB, VA = no connect −2.5 ±0.25 +2.5 LSB
∆R
AB
TA = 25°C −20 +20 %
Resistance Temperature Coefficient (∆RAB/RAB )/∆T VAB = VDD, wiper = no connect 35 ppm/°C
RWB (Wiper Resistance) R
WB
Code = 0x00, VDD = 5 V 160 200 Ω
DC CHARACTERISTICS—POTENTIOMETER DIVIDER MODE (Specifications Apply to All VRs)
Differential Nonlinearity
Integral Nonlinearity
4
4
DNL −1 ±0.1 +1 LSB
INL −1 ±0.3 +1 LSB
Voltage Divider Temperature Coefficient (∆VW/VW)/∆T Code = 0x80 15 ppm/°C
Full-Scale Error V
Zero-Scale Error V
WFSE
WZSE
Code = 0xFF −2.5 −1 0 LSB
Code = 0x00 0 1 2.5 LSB
RESISTOR TERMINALS
Voltage Range
Capacitance6 A, B C
5
V
A,B,W
A,B
GND V
f = 1 MHz, measured to GND,
45 pF
Code = 0x80
Capacitance6 W C
W
f = 1 MHz, measured to GND,
60 pF
Code = 0x80
Common-Mode Leakage I
CM
VA = VB = VDD/2 1 nA
DIGITAL INPUTS AND OUTPUTS
Input Logic High V
Input Logic Low V
Input Logic High V
Input Logic Low V
Input Current I
Input Capacitance C
IH
IL
IH
IL
IL
IL
VDD = 5 V 2.4 V
VDD = 5 V 0.8 V
VDD = 3 V 2.1 V
VDD = 3 V 0.6 V
VIN = 0 V or 5 V ±1 µA
5 pF
POWER SUPPLIES
Power Supply Range V
Supply Current I
Power Dissipation P
DD RANGE
DD
DISS
Power Supply Sensitivity PSS
2.7 5.5 V
VIH = 5 V or VIL = 0 V 3.5 6 µA
VIH = 5 V or VIL = 0 V, VDD = 5 V 30 µW
= 5 V ± 10%, Code =
V
DD
±0.02 ±0.08 %/%
midscale
DYNAMIC CHARACTERISTICS
Bandwidth −3 dB BW
= 10 kΩ/50 kΩ/100 kΩ,
R
AB
600/100/40 kHz
Code = 0x80
Total Harmonic Distortion THD
VW Settling Time (10 kΩ/50 kΩ/100 kΩ) t
S
W
VA = 1 V rms, VB = 0 V,
f = 1 kHz, R
= 10 kΩ
AB
VA = 5 V, VB = 0 V,
0.1 %
2 µs
±1 LSB error band
Resistor Noise Voltage Density e
See notes at end of section.
N_WB
RWB = 5 kΩ, RS = 0 9
1
Max Unit
V
DD
nV/√Hz
Rev. A | Page 4 of 20
AD5162
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TIMING CHARACTERISTICS—ALL VERSIONS
Table 3. VDD = +5 V ± 10%, or +3 V ± 10%; VA = VDD; VB = 0 V; −40°C < TA < +125°C; unless otherwise noted
Parameter Symbol Conditions Min Typ
SPI INTERFACE TIMING CHARACTERISTICS9 (Specifications Apply to All Parts)
Clock Frequency f
Input Clock Pulse Width tCH, t
Data Setup Time t
Data Hold Time t
CS Setup Time
CS High Pulse Width
CLK Fall to CS Fall Hold Time
CLK Fall to CS Rise Hold Time
CS Rise to Clock Rise Setup
See notes at end of section.
CLK
Clock level high or low 20 ns
5 ns
5 ns
15 ns
40 ns
0 ns
0 ns
10 ns
DS
DH
t
CSS
t
CSW
t
CSH0
t
CSH1
t
CS1
CL
NOTES
1
Typical specifications 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 resistance and the minimum resistance wiper
positions. R-DNL measures the relative step change from ideal between successive tap positions. Parts are guaranteed monotonic.
3
VAB = VDD, wiper (VW) = no connect.
4
INL and DNL are measured at VW with the RDAC configured as a potentiometer divider similar to a voltage output DAC converter. VA = VDD and VB = 0 V.
DNL specification limits of ±1 LSB maximum are guaranteed monotonic operating conditions.
5
Resistor terminals A, B, W have no limitations on polarity with respect to each other.
6
Guaranteed by design and not subject to production test.
7
P
is calculated from (IDD × VDD). CMOS logic level inputs result in minimum power dissipation.
DISS
8
All dynamic characteristics use VDD = 5 V.
9
See timing diagrams for locations of measured values.
1
Max Unit
25 MHz
Rev. A | Page 5 of 20
AD5162
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ABSOLUTE MAXIMUM RATINGS
Table 4. TA = 25°C, unless otherwise noted
Parameter Value
VDD to GND –0.3 V to +7 V
VA, VB, VW to GND V
Terminal Current, Ax to Bx, Ax to Wx,
Bx to Wx
Digital Inputs and Output Voltage to GND 0 V to 7 V
Operating Temperature Range –40°C to +125°C
Maximum Junction Temperature (T
Storage Temperature –65°C to +150°C
Lead Temperature (Soldering, 10 s) 300°C
Thermal Resistance2 θJA: MSOP-10
1
Maximum terminal current is bounded by the maximum current handling of
2
Package power dissipation = (T
1
Pulsed ±20 mA
Continuous ±5 mA
JMAX
the switches, maximum power dissipation of the package, and maximum
applied voltage across any two of the A, B, and W terminals at a given
resistance.
− TA)/θJA.
JMAX
DD
) 150°C
230°C/W
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on
the human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance
degradation or loss of functionality.
Rev. A | Page 6 of 20
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