AD AD5241BRU100

a
I2C® Compatible
256-Position Digital Potentiometers
AD5241/AD5242
FEATURES
256 Positions
10 k, 100 k, 1 M
Low Tempco 30 ppm/C
Internal Power ON Midscale Preset
Single-Supply 2.7 V to 5.5 V or
Dual-Supply 2.7 V for AC or Bipolar Operation
I2C Compatible Interface with Readback Capability
Extra Programmable Logic Outputs
Self-Contained Shutdown Feature
Extended Temperature Range –40C to +105C
FUNCTIONAL BLOCK DIAGRAM
A1
W1 B1
O1
O2
AD5241
SHDN
VDD
RDAC
REGISTER 1
REGISTER 2
VSS
ADDR
DECODE
APPLICATIONS
Multimedia, Video, and Audio
Communications
Mechanical Potentiometer Replacement
Instrumentation: Gain, Offset Adjustment
Programmable Voltage-to-Current Conversion
Line Impedance Matching
SDA
SCL
GND
8
SERIAL INPUT REGISTER
AD0
A
PWR-ON
RESET
AD1
W1 B1
A2
W2 B2
O1
O2
1
SHDN
REGISTER
GENERAL DESCRIPTION
The AD5241/AD5242 provide a single-/dual-channel, 256position, digitally controlled variable resistor (VR) device. These
devices perform 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.
For AD5242, the fixed A-to-B terminal resistance of 10 kΩ,
100 kΩ, or 1 MΩ has a 1% channel-to-channel matching
tolerance. The nominal temperature coefficient of both parts is
30 ppm/°C.
VDD
RDAC
REGISTER 1
RDAC
REGISTER 2
VSS
ADDR
DECODE
AD5242
1
SDA
SCL
GND
8
SERIAL INPUT REGISTER
AD0
PWR-ON
RESET
AD1
Wiper position programming defaults to midscale at system
power ON. Once powered, the VR wiper position is programmed
by an I2C compatible 2-wire serial data interface. Both parts
have available two extra programmable logic outputs that
enable users to drive digital loads, logic gates, LED drivers, and
analog switches in their system.
The AD5241/AD5242 are available in surface-mount (SOIC-14/16) packages and, for ultracompact solutions, TSSOP-14/-16
packages. All parts are guaranteed to operate over the
extended temperature range of –40°C to +105°C. For 3-wire,
SPI compatible interface applications, please refer to AD5200,
AD5201, AD5203, AD5204, AD5206, AD5231*, AD5232*,
AD5235*, AD7376, AD8400, AD8402, and AD8403 products.
*Nonvolatile digital potentiometer
I2C is a registered trademark of Philips Corporation.
REV. B
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. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
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
© Analog Devices, Inc., 2002
AD5241/AD5242–SPECIFICATIONS
10 k, 100 k, 1 M VERSION
Parameter
(VDD = 3 V 10% or 5 V 10%, VA = +VDD, VB = 0 V, –40C < TA < +105C, unless
otherwise noted.)
Symbol
Conditions
DC CHARACTERISTICS, RHEOSTAT MODE (Specifications apply to all VRs.)
R-DNL
RWB, VA = No Connect
Resistor Differential Nonlinearity2
Resistor Integral Nonlinearity2
R-INL
RWB, VA = No Connect
Nominal Resistor Tolerance
DR
TA = 25°C, RAB = 10 kΩ
DR
TA = 25°C, RAB = 100 kΩ/1 MΩ
Resistance Temperature Coefficient RAB/DT
VAB = VDD, Wiper = No Connect
Wiper Resistance
RW
IW = VDD /R, VDD = 3 V or 5 V
Min
Typ1 Max
Unit
–1
–2
–30
–30
± 0.4
± 0.5
+1
+2
+30
+50
30
60
120
LSB
LSB
%
%
ppm/°C
Ω
DC CHARACTERISTICS, POTENTIOMETER DIVIDER MODE (Specifications apply to all VRs.)
Resolution
N
8
DNL
–1
Differential Nonlinearity3
INL
–2
Integral Nonlinearity3
Voltage Divider Temperature
Code = 80H
Coefficient
DVW/DT
Code = FFH
–1
Full-Scale Error
VWFSE
Zero-Scale Error
VWZSE
Code = 00H
0
± 0.4
± 0.5
+1
+2
Bits
LSB
LSB
5
–0.5
0.5
0
1
ppm/°C
LSB
LSB
RESISTOR TERMINALS
Voltage Range4
Capacitance5 A, B
Capacitance5 W
Common-Mode Leakage
VA, B, W
CA, B
CW
ICM
45
60
1
DIGITAL INPUTS
Input Logic High (SDA and SCL)
Input Logic Low (SDA and SCL)
Input Logic High (AD0 and AD1)
Input Logic Low (AD0 and AD1)
Input Logic High
Input Logic Low
Input Current
Input Capacitance5
VIH
VIL
VIH
VIL
VIH
VIL
IIL
CIL
DIGITAL OUTPUT
Output Logic Low (SDA)
Output Logic Low (O1 and O2)
Output Logic High (O1 and O2)
Three-State Leakage Current (SDA)
Output Capacitance5
VOL
VOL
VOL
VOH
IOZ
COZ
IOL = 3 mA
IOL = 6 mA
ISINK = 1.6 mA
ISOURCE = 40 µA
VIN = 0 V or 5 V
POWER SUPPLIES
Power Single-Supply Range
Power Dual-Supply Range
Positive Supply Current
Negative Supply Current
Power Dissipation6
Power Supply Sensitivity
VDD RANGE
VDD/SS RANGE
IDD
ISS
PDISS
PSS
VSS = 0 V
± 2.3
VIH = 5 V or VIL = 0 V
VSS = –2.5 V, VDD = +2.5 V
VIH = 5 V or VIL = 0 V, VDD = 5 V
DYNAMIC CHARACTERISTICS5, 7, 8
Bandwidth –3 dB
BW_10 kΩ
BW_100 kΩ
BW_1 MΩ
Total Harmonic Distortion
THDW
VW Settling Time
tS
Resistor Noise Voltage
eN_WB
VSS
f = 1 MHz, Measured to GND, Code = 80H
f = 1 MHz, Measured to GND, Code = 80H
VA = VB = VW
VDD = 5 V
VDD = 5 V
VDD = 3 V
VDD = 3 V
VIN = 0 V or 5 V
0.7 VDD
–0.5
2.4
0
2.1
0
VDD
V
pF
pF
nA
VDD + 0.5
+0.3 VDD
VDD
0.8
VDD
0.6
1
V
V
V
V
V
V
µA
pF
0.4
0.6
0.4
V
V
V
V
µA
pF
3
4
3
RAB = 10 kΩ, Code = 80H
RAB = 100 kΩ, Code = 80H
RAB = 1 MΩ, Code = 80H
VA = 1 V rms + 2 V dc,
VB = 2 V dc, f = 1 kHz
VA = VDD, VB = 0 V, ± 1 LSB Error Band,
RAB = 10 kΩ
RWB = 5 kΩ, f = 1 kHz
–2–
2.7
±1
8
5.5
± 2.7
0.1
50
+0.1 –50
0.5
250
–0.01 +0.002 +0.01
V
V
µA
µA
µW
%/%
650
69
6
0.005
kHz
kHz
kHz
%
2
µs
14
nV√Hz
REV. B
AD5241/AD5242
Parameter
Symbol
Conditions
INTERFACE TIMING CHARACTERISTICS (Applies to all parts.5, 9)
SCL Clock Frequency
fSCL
t1
tBUF Bus Free Time between
STOP and START
t2
After this period, the first clock
tHD; STA Hold Time (Repeated START)
pulse is generated.
tLOW Low Period of SCL Clock
t3
t4
tHIGH High Period of SCL Clock
tSU; STA Setup Time for Repeated
START Condition
t5
t6
tHD; DAT Data Hold Time
tSU; DAT Data Setup Time
t7
t8
tR Rise Time of Both
SDA and SCL Signals
tF Fall Time of Both SDA and SCL Signals t9
tSU; STO Setup Time for STOP Condition
t10
Min
0
1.3
Typ1 Max
400
600
1.3
0.6
Unit
kHz
µs
ns
50
600
µs
µs
300
ns
ns
ns
ns
300
ns
900
100
NOTES
1
Typicals represent average readings at 25°C, 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. See Test Circuits.
3
INL and DNL are measured at V W with the RDAC configured as a potentiometer divider similar to a voltage output D/A converter. V A = VDD and VB = 0 V.
DNL specification limits of ± 1 LSB maximum are guaranteed monotonic operating conditions. See Figure 10.
4
Resistor terminals A, B, W have no limitations on polarity with respect to each other.
5
Guaranteed by design and not subject to production test.
6
PDISS is calculated from (I DD × VDD). CMOS logic level inputs result in minimum power dissipation.
7
Bandwidth, noise, and settling time are dependent on the terminal resistance value chosen. The lowest R value results in the fastest settling time and highest bandwidth. The highest R value results in the minimum overall power consumption.
8
All dynamic characteristics use V DD = 5 V.
9
See timing diagram for location of measured values.
Specifications subject to change without notice.
REV. B
–3–
AD5241/AD5242
Thermal Resistance θJA
SOIC (SOIC-14) . . . . . . . . . . . . . . . . . . . . . . . . . 158°C/W
SOIC (SOIC-16) . . . . . . . . . . . . . . . . . . . . . . . . . . 73°C/W
TSSOP-14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206°C/W
TSSOP-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180°C/W
Maximum Junction Temperature (TJ max) . . . . . . . . . . 150°C
Package Power Dissipation PD = (TJ max – TA)/θJA
Storage Temperature . . . . . . . . . . . . . . . . . . –65°C to +150°C
Lead Temperatures
R-14, R-16A, RU-14, RU-16 (Vapor Phase, 60 sec) . 215°C
R-14, R-16A, RU-14, RU-16 (Infrared, 15 sec) . . . . . 220°C
ABSOLUTE MAXIMUM RATINGS *
(TA = 25°C, unless otherwise noted.)
VDD to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V, +7 V
VSS to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 V , –7 V
VDD to VSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
VA, VB, VW to GND . . . . . . . . . . . . . . . . . . . . . . . . . . VSS, VDD
AX–BX, AX–WX, BX–WX at 10 kΩ in TSSOP-14 . . . ± 5.0 mA*
AX–BX, AX–WX, BX–WX at 100 kΩ in TSSOP-14 . . ± 1.5 mA*
AX–BX, AX–WX, BX–WX at 1 MΩ in TSSOP-14 . . . ± 0.5 mA*
Digital Input Voltage to GND . . . . . . . . . . . . . . . . . . 0 V, 7 V
Operating Temperature Range . . . . . . . . . . –40°C to +105°C
*Max current increases at lower resistance and different packages.
ORDERING GUIDE
Model
Number of
Channels
End to End
RAB ()
Temperature
Range (C)
Package
Description
Package
Option
Number of
Devices per
Container
AD5241BR10
AD5241BR10-REEL7
AD5241BRU10-REEL7
AD5241BR100
AD5241BR100-REEL7
AD5241BRU100-REEL7
AD5241BR1M
AD5241BRU1M-REEL7
AD5242BR10
AD5242BR10-REEL7
AD5242BRU10-REEL7
AD5242BR100
AD5242BR100-REEL7
AD5242BRU100-REEL7
AD5242BR1M
AD5242BRU1M-REEL7
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
10 k
10 k
10 k
100 k
100 k
100 k
1M
1M
10 k
10 k
10 k
100 k
100 k
100 k
1M
1M
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
–40 to +105
SOIC-14
SOIC-14
TSSOP-14
SOIC-14
SOIC-14
TSSOP-14
SOIC-14
TSSOP-14
SOIC-16
SOIC-16
TSSOP-16
SOIC-16
SOIC-16
TSSOP-16
SOIC-16
TSSOP-16
R-14
R-14
RU-14
R-14
R-14
RU-14
R-14
RU-14
R-16A
R-16A
RU-16
R-16A
R-16A
RU-16
R-16A
RU-16
56
1000
1000
56
1000
1000
56
1000
48
1000
1000
48
1000
1000
48
1000
NOTES
1
The AD5241/AD5242 die size is 69 mil × 78 mil, 5,382 sq. mil. Contains 386 transistors for each channel. Patent Number 5495245 applies.
2
TSSOP packaged units are only available in 1,000-piece quantity Tape and Reel.
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
the AD5241/AD5242 feature 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.
–4–
WARNING!
ESD SENSITIVE DEVICE
REV. B
AD5241/AD5242
AD5241 PIN CONFIGURATION
AD5242 PIN CONFIGURATION
A1 1
14
O1
O1 1
16
A2
W1 2
13
NC
A1 2
15
W2
12
O2
W1 3
14
B2
11
VSS
10
DGND
B1 3
VDD 4
SHDN 5
AD5241
TOP VIEW
(Not to Scale)
AD5242
O2
TOP VIEW
VDD 5 (Not to Scale) 12 VSS
B1 4
13
SCL 6
9
AD1
SHDN 6
11
DGND
SDA 7
8
AD0
SCL 7
10
AD1
SDA 8
9
AD0
NC = NO CONNECT
AD5241 PIN FUNCTION DESCRIPTIONS
AD5242 PIN FUNCTION DESCRIPTIONS
Pin
Mnemonic
Description
Pin
Mnemonic
Description
1
2
3
4
A1
W1
B1
VDD
1
2
3
4
5
SHDN
O1
A1
W1
B1
VDD
5
Resistor Terminal A1
Wiper Terminal W1
Resistor Terminal B1
Positive power supply, specified for operation from 2.2 V to 5.5 V.
Active low, asynchronous connection of
Wiper W to Terminal B, and open circuit
of Terminal A. RDAC register contents
unchanged. SHDN should tie to VDD if
not used.
Serial Clock Input
Serial Data Input/Output
Programmable address bit for multiple
package decoding. Bits AD0 and AD1
provide four possible addresses.
Programmable address bit for multiple
package decoding. Bits AD0 and AD1
provide four possible addresses.
Common Ground
Negative power supply, specified for
operation from 0 V to –2.7 V.
Logic Output Terminal O2
No Connect
Logic Output Terminal O1
6
SHDN
7
8
9
SCL
SDA
AD0
10
AD1
11
12
DGND
VSS
13
14
15
16
O2
B2
W2
A2
Logic Output Terminal O1
Resistor Terminal A1
Wiper Terminal W1
Resistor Terminal B1
Positive power supply, specified for operation from 2.2 V to 5.5 V.
Active low, asynchronous connection of
Wiper W to Terminal B, and open circuit
of Terminal A. RDAC register contents
unchanged. SHDN should tie to VDD if
not used.
Serial Clock Input
Serial Data Input/Output
Programmable address bit for multiple
package decoding. Bits AD0 and AD1
provide four possible addresses.
Programmable address bit for multiple
package decoding. Bits AD0 and AD1
provide four possible addresses.
Common Ground
Negative power supply, specified for
operation from 0 V to –2.7 V.
Logic Output Terminal O2
Resistor Terminal B2
Wiper Terminal W2
Resistor Terminal A2
6
7
8
SCL
SDA
AD0
9
AD1
10
11
DGND
VSS
12
13
14
O2
NC
O1
REV. B
–5–
AD5241/AD5242
t8
SDA
t1
t8
t9
t2
SCL
t4
t2
P
t3
S
t7
t5
t 10
S
t6
P
Figure 1. Detail Timing Diagram
Data of AD5241/AD5242 is accepted from the I2C bus in the following serial format:
S
0
1
0
1
1
AD1 AD0 R/W
A
A/B RS
SD
SLAVE ADDRESS BYTE
O1
O2
X
X
X
A
D7
D6
D5
INSTRUCTION BYTE
D4
D3
D2
D1
D0
A
P
DATA BYTE
where:
S = Start Condition
P = Stop Condition
A = Acknowledge
X = Don’t Care
AD1, AD0 = Package pin programmable address bits. Must be matched with the logic states at Pins AD1 and AD0.
R/W = Read Enable at High and output to SDA. Write Enable at Low.
A/B = RDAC subaddress select. ‘0’ for RDAC1 and ‘1’ for RDAC2.
RS = Midscale reset, active high.
SD = Shutdown in active high. Same as SHDN except inverse logic.
O1, O2 = Output logic pin latched values.
D7, D6, D5, D4, D3, D2, D1, D0 = Data Bits.
9
1
1
9
1
9
SCL
SDA
0
1
0
1
1
AD1
AD0
A/B
R/W
RS
SD
O1
O2
X
X
X
ACK BY
AD5241
START BY
MASTER
D7
D6
D5
D4
D3
D2
ACK BY
AD5241
FRAME 1
SLAVE ADDRESS BYTE
FRAME 2
INSTRUCTION BYTE
FRAME 3
DATA BYTE
D1
D0
ACK BY
AD5241
STOP BY
MASTER
Figure 2. Writing to the RDAC Serial Register
9
1
1
9
SCL
SDA
0
1
0
1
1
AD1
AD0
R/W
D7
D6
D5
D4
D3
D2
D1
D0
ACK BY
AD5241
START BY
MASTER
NO ACK BY
MASTER
STOP BY
FRAME 2
MASTER
DATA BYTE FROM PREVIOUSLY SELECTED
RDAC REGISTER IN WRITE MODE
FRAME 1
SLAVE ADDRESS BYTE
Figure 3. Reading Data from a Previously Selected RDAC Register in Write Mode
–6–
REV. B
Typical Performance Characteristics–AD5241/AD5242
0.50
VDD = +2.7V
VDD = +5.5V
VDD = 2.7V
0.5
VDD /VSS = +2.7V/0V
0
–0.5
VDD = +2.7V
VDD = +5.5V
VDD = 2.7V
POTENTIOMETER MODE
INTEGRAL NONLINEARITY – LSB
RHEOSTAT MODE DIFFERENTIAL
NONLINEARITY – LSB
1.0
VDD /VSS = +5.5V/0V, 2.7V
0.25
VDD /VSS = 2.7V
0
VDD /VSS = +2.7V/0V, +5.5V/0V
–0.25
–1.0
–0.50
0
32
64
96
128
160
CODE – Decimal
192
224
256
0
32
128
160
224
192
256
TPC 4. INL vs. Code
1.0
10000
VDD = 2.7V
TA = 25C
VDD /VSS = +2.7V/0V
NOMINAL RESISTANCE – k
VDD = +2.7V
VDD = +5.5V
VDD = 2.7V
0.5
0
VDD /VSS = +5.5V/0V, 2.7V
–0.5
0
32
64
96
128
160
192
224
1M
1000
100k
100
10k
10
1
–40
–1.0
256
–20
0
CODE – Decimal
TPC 2. RINL vs. Code
40
20
TEMPERATURE – C
80
60
TPC 5. Nominal Resistance vs. Temperature
10000
0.25
VDD = +2.7V
VDD = +5.5V
VDD = 2.7V
IDD - SUPPLY CURRENT – A
POTENTIOMETER MODE
DIFFERENTIAL NONLINEARITY – LSB
96
CODE – Decimal
TPC 1. RDNL vs. Code
RHEOSTAT MODE INTEGRAL
NONLINEARITY – LSB
64
0.13
VDD /VSS = +2.7V/0V, +5.5V/0V, 2.7V
0
–0.13
VDD = 5V
1000
VDD = 3V
100
10
VDD = 2.5V
–0.25
1
0
32
64
96
128
160
CODE – Decimal
192
224
256
0
TPC 3. DNL vs. Code
REV. B
1
2
3
INPUT LOGIC VOLTAGE – V
4
TPC 6. Supply Current vs. Input Logic Voltage
–7–
5
AD5241/AD5242
100
0.1
TA = 25C
RAB = 10k
VDD = 5.5V
90
WIPER RESISTANCE – SHUTDOWN CURRENT – A
80
0.01
VDD /VSS = +2.7V/0V
70
60
50
VDD /VSS = 2.7V/0V
40
30
VDD /VSS = +5.5V/0V
20
0.001
–40
10
0
–20
20
40
60
–3
80
–2
–1
TPC 7. Shutdown Current vs. Temperature
2
3
4
6
5
300
VDD /VSS = 2.7V/0V
TA = 25C
60
10M VERSION
A – VDD /V S S = 5.5V/0V
CODE = FF
250
50
IDD – SUPPLY CURRENT A
POTENTIOMETER MODE TEMPCO – ppm/ C
1
TPC 10. Incremental Wiper Contact vs. VDD/VSS
70
10k VERSION
40
100k VERSION
30
20
10
0
–10
D
B – VDD /V SS = 3.3V/0V
CODE = FF
200
A
C – VDD /V SS = 2.5V/0V
CODE = FF
150
D – VDD /V SS = 5.5V/0V
CODE = 55
E – VDD /V SS = 3.3V/0V
CODE = 55
100
E
B
F – VDD /V SS = 2.5V/0V
CODE = 55
50
F
C
–20
–30
0
32
64
96
128
160
192
224
0
10
256
100
FREQUENCY – kHz
CODE – Decimal
TPC 8. ⌬VWB/⌬T Potentiometer Mode Tempco
1000
TPC 11. Supply Current vs. Frequency
120
6
VDD /VSS = 2.7V/0V
TA = 25C
100
100k VERSION
FFH
0
80
–6
60
–12
40
–18
GAIN – dB
RHEOSTAT MODE TEMPCO – ppm/ C
0
COMMON MODE – V
TEMPERATURE – C
20
0
80H
40H
20H
10H
–24
08H
–30
04H
–20
–36
02H
10k VERSION
–40
–42
01H
10M VERSION
–60
–48
–80
0
32
64
96
128
160
192
224
–54
100
256
CODE – Decimal
TPC 9. ⌬RWB/⌬T Rheostat Mode Tempco
1k
10k
FREQUENCY – Hz
100k
1M
TPC 12. AD5242 10 kΩ Gain vs. Frequency vs. Code
–8–
REV. B
AD5241/AD5242
6
6
FFH
0
80H
–6
GAIN – dB
GAIN – dB
10H
–24
08H
–30
04H
–36
20H
–18
10H
–24
08H
–30
04H
–36
02H
–42
40H
–12
20H
–18
80H
–6
40H
–12
FFH
0
02H
–42
01H
–48
01H
–48
–54
100
1k
10k
FREQUENCY – Hz
–54
100
100k
TPC 13. AD5242 100 kΩ Gain vs. Frequency vs. Code
OPERATION
The AD5241/AD5242 provide a single-/dual-channel, 256position digitally controlled variable resistor (VR) device. The
terms VR, RDAC, and programmable resistor are commonly
used interchangeably to refer to digital potentiometer.
To program the VR settings, refer to the Digital Interface section. Both parts have an internal power ON preset that places
the wiper in midscale during power-on, which simplifies the
fault condition recovery at power-up. In addition, the shutdown
SHDN Pin of AD5241/AD5242 places the RDAC in an almost
zero power consumption state where Terminal A is open circuited
and Wiper W is connected to Terminal B, resulting in only
leakage current being consumed in the VR structure. During
shutdown, the VR latch contents are maintained when the RDAC
is inactive. When the part is returned from shutdown, the stored
VR setting will be applied to the RDAC.
A
SHDN
SWSHDN
D7
D6
D5
D4
D3
D2
D1
D0
R
N
SW 2–1
R
N
SW 2–2
10k
FREQUENCY – Hz
100k
TPC 14. AD5242 1 MΩ Gain vs. Frequency vs. Code
PROGRAMMING THE VARIABLE RESISTOR
Rheostat Operation
The nominal resistance of the RDAC between Terminals A and
B is available in 10 kΩ, 100 kΩ, and 1 MΩ. The final two or
three digits of the part number determine the nominal resistance
value, e.g., 10 kΩ = 10; 100 kΩ = 100; 1 MΩ = 1 M. The
nominal resistance (RAB ) of the VR has 256 contact points
accessed by the Wiper Terminal, plus the B Terminal contact. The 8-bit data in the RDAC latch is decoded to select
one of the 256 possible settings. Assume a 10 kΩ part is used;
the wiper’s first connection starts at the B Terminal for data
00H. Since there is a 60 Ω wiper contact resistance, such connection yields a minimum of 60 Ω resistance between Terminals
W and B. The second connection is the first tap point that corresponds to 99 Ω (RWB = RAB /256 + RW = 39 + 60) for data
01H. The third connection is the next tap point representing
138 Ω (39 × 2 + 60) for data 02H, and so on. Each LSB data
value increase moves the wiper up the resistor ladder until the
last tap point is reached at 10021 Ω [RAB – 1 LSB + RW].
Figure 4 shows a simplified diagram of the equivalent RDAC
circuit where the last resistor string will not be accessed; therefore, there is 1 LSB less of the nominal resistance at full scale in
addition to the wiper resistance.
The general equation determining the digitally programmed
resistance between W and B is:
W
RWB ( D ) = D × R AB + RW
256
SW1
R
RDAC
LATCH
AND
DECODER
1k
R
R
RAB
/2N
SW0
where:
D
B
(1)
DIGITAL CIRCUITRY
OMITTED FOR CLARITY
is the decimal equivalent of the binary code between 0
and 255, which is loaded in the 8-bit RDAC register.
RAB is the nominal end-to-end resistance.
Figure 4. Equivalent RDAC Circuit
RW is the wiper resistance contributed by the on resistance
of the internal switch.
Again, if RAB = 10 kΩ and the A Terminal can be either open
circuit or tied to W, the following output resistance at RWB will
be set for the following RDAC latch codes.
REV. B
–9–
AD5241/AD5242
which can be simplified to
D
(DEC)
RWB
()
Output State
255
128
1
0
10021
5060
99
60
Full-Scale (RWB – 1 LSB + RW)
Midscale
1 LSB
Zero-Scale (Wiper Contact Resistance)
Note that in the zero-scale condition, a finite wiper resistance of
60 Ω is present. Care should be taken to limit the current flow
between W and B in this state to a maximum current of no more
than ± 20 mA. Otherwise, degradation or possible destruction of
the internal switch contact can occur.
For RAB = 10 kΩ, and the B Terminal can be either open circuit
or tied to W. The following output resistance RWA will be set for
the following RDAC latch codes.
RWA
()
Output State
255
128
1
0
99
5060
10021
10060
Full-Scale
Midscale
1 LSB
Zero-Scale
where D is the decimal equivalent of the binary code between 0
to 255 that is loaded in the 8-bit RDAC register.
For more accurate calculation including the effects of wiper
resistance, VW can be found as:
VW (D )=
(5)
DIGITAL INTERFACE
2-Wire Serial Bus
The AD5241/AD5242 are controlled via an I2C compatible
serial bus. The RDACs are connected to this bus as slave devices.
Referring to Figures 2 and 3, the first byte of AD5241/AD5242
is a Slave Address Byte. It has a 7-bit slave address and an R/W
Bit. The 5 MSBs are 01011 and the following two bits are
determined by the state of the AD0 and AD1 Pins of the device.
AD0 and AD1 allow users to use up to four of these devices on
one bus.
1. The master initiates data transfer by establishing a START
condition, which is when a high-to-low transition on the SDA
line occurs while SCL is high (Figure 2). The following byte
is the Slave Address Byte, Frame 1, which consists of the
7-bit slave address followed by an R/W Bit (this bit determines whether data will be read from or written to the
slave device).
The slave whose address corresponds to the transmitted
address will respond by pulling the SDA line low during the
ninth clock pulse (this is termed the Acknowledge Bit). At
this stage, all other devices on the bus remain idle while the
selected device waits for data to be written to or read from its
serial register. If the R/W Bit is high, the master will read
from the slave device. If the R/W Bit is low, the master will
write to the slave device.
PROGRAMMING THE POTENTIOMETER DIVIDER
Voltage Output Operation
The digital potentiometer easily generates output voltages at
wiper-to-B and wiper-to-A to be proportional to the input voltage at A-to-B. Unlike the polarity of VDD – VSS, which must be
positive, voltage across A–B, W–A, and W–B can be at either
polarity provided that VSS is powered by a negative supply.
If ignoring the effect of the wiper resistance for approximation,
connecting the A Terminal to 5 V and the B Terminal to ground
produces an output voltage at the wiper-to-B starting at 0 V up
to 1 LSB less than 5 V. Each LSB of voltage is equal to the voltage
applied across Terminal AB divided by the 256 positions of the
potentiometer divider. Since AD5241/AD5242 can be supplied by dual supplies, the general equation defining the output
voltage at VW with respect to ground for any valid input voltage
applied to Terminals A and B is:
D
256 − D
VA +
VB
256
256
RWB (D )
RWA (D )
VA +
VB
RAB
RAB
The 2-wire I2C serial bus protocol operates as follows:
The typical distribution of the nominal resistance RAB from
channel to channel matches within ± 1% for AD5242. Deviceto-device matching is process lot dependent and it is possible to
have ± 30% variation. Since the resistance element is processed
in thin film technology, the change in RAB with temperature has
no more than a 30 ppm/°C temperature coefficient.
VW (D) =
(4)
Operation of the digital potentiometer in the Divider Mode results
in a more accurate operation over temperature. Unlike the
Rheostat Mode, the output voltage is dependent on the ratio
of the internal resistors RWA and RWB, and not the absolute
values; therefore, the temperature drift reduces to 5 ppm/°C.
(2)
D
(DEC)
D
VAB + VB
256
where RWB(D) and RWA(D) can be obtained from Equations 1
and 2.
Similar to the mechanical potentiometer, the resistance of the
RDAC between Wiper W and Terminal A also produces a digitally controlled resistance, RWA. When these terminals are used,
the B Terminal can be opened or tied to the Wiper Terminal.
Setting the resistance value for RWA starts at a maximum value
of resistance and decreases as the data loaded in the latch
increases in value. The general equation for this operation is:
RWA ( D ) = 256 – D × R AB + RW
256
VW (D) =
(3)
2. A Write operation contains an extra Instruction Byte more
than the Read operation. This Instruction Byte, Frame 2,
in Write Mode follows the Slave Address Byte. The MSB of
the Instruction Byte labeled A/B is the RDAC subaddress
select. A “low” selects RDAC1 and a “high” selects RDAC2
for the dual-channel AD5242. Set A/B to low for AD5241.
The second MSB, RS, is the midscale reset. A logic high of
this bit moves the wiper of a selected RDAC to the center tap
where RWA = RWB. The third MSB, SD, is a shutdown bit. A
logic high on SD causes the RDAC open circuit at Terminal A
while shorting the wiper to Terminal B. This operation yields
almost a 0 Ω in Rheostat Mode or 0 V in Potentiometer
Mode. This SD Bit serves the same function as the SHDN
–10–
REV. B
AD5241/AD5242
Pin except that SHDN Pin reacts to active low. The following two bits are O 2 and O1. They are extra programmable
logic outputs that users can use to drive other digital loads,
logic gates, LED drivers, analog switches, and the like. The
three LSBs are Don’t Care. See Figure 2.
3. After acknowledging the Instruction Byte, the last byte in
Write Mode is the Data Byte, Frame 3. Data is transmitted
over the serial bus in sequences of nine clock pulses (eight
data bits followed by an Acknowledge Bit). The transitions
on the SDA line must occur during the low period of SCL
and remain stable during the high period of SCL (Figure 2).
4. Unlike the Write Mode, the Data Byte follows immediately
after the acknowledgment of the Slave Address Byte in Read
Mode, Frame 2. Data is transmitted over the serial bus
in sequences of nine clock pulses (slightly different than the
Write Mode, there are eight data bits followed by a No
Acknowledge logic 1 Bit in Read Mode). Similarly, the transitions on the SDA line must occur during the low period of
SCL and remain stable during the high period of SCL. See
Figure 3.
5. When all Data Bits have been read or written, a STOP condition is established by the master. A STOP condition is
defined as a low-to-high transition on the SDA line while
SCL is high. In Write Mode, the master will pull the SDA line
high during the tenth clock pulse to establish a STOP condition (see Figure 2). In Read Mode, the master will issue a
No Acknowledge for the ninth clock pulse (i.e., the SDA
line remains high). The master will then bring the SDA
line low before the tenth clock pulse, which goes high to
establish a STOP condition (see Figure 3).
A repeated Write function gives the user flexibility to update the
RDAC output a number of times after addressing and instructing the part only once. During the Write cycle, each Data Byte
will update the RDAC output. For example, after the RDAC
has acknowledged its Slave Address and Instruction Bytes, the
RDAC output will be updated. If another byte is written to the
RDAC while it is still addressed to a specific slave device with
the same instruction, this byte will update the output of the
selected slave device. If different instructions are needed, the
Write Mode has to start a whole new sequence with a new Slave
Address, Instruction, and Data Bytes transferred again. Similarly, a repeated Read function of the RDAC is also allowed.
each device to be written to or read from independently. The
master device output bus line drivers are open-drain pulldowns in a fully I2C compatible interface. Note, a device will be
addressed properly only if the bit information of AD0 and
AD1 in the Slave Address Byte matches with the logic inputs at
pins AD0 and AD1 of that particular device.
5V
RP
RP
SDA
MASTER
SCL
VDD
SDA SCL
SDA SCL
VDD
VDD
SDA SCL
SDA SCL
AD1
AD1
AD1
AD1
AD0
AD0
AD0
AD0
AD5242
AD5242
AD5242
AD5242
Figure 5. Multiple AD5242 Devices on One Bus
LEVEL-SHIFT FOR BIDIRECTIONAL INTERFACE
While most old systems may be operated at one voltage, a new
component may be optimized at another. When they operate the
same signal at two different voltages, a proper method of levelshifting is needed. For instance, one can use a 3.3 V E2PROM
to interface with a 5 V digital potentiometer. A level-shift scheme
is needed in order to enable a bidirectional communication so
that the setting of the digital potentiometer can be stored to and
retrieved from the E2PROM. Figure 6 shows one of the techniques. M1 and M2 can be N-Ch FETs 2N7002 or low threshold
FDV301N if VDD falls below 2.5 V.
VDD2 = 5V
VDD2 = 3.3V
RP
G
RP
S
RP
RP
D
SDA1
S
SCL1
SDA2
G
M1
D
SCL2
M2
3.3V
E2PROM
5V
AD5242
Figure 6. Level-Shift for Different Voltage Devices Operation
VDD
MP
READBACK RDAC VALUE
Specific to the AD5242 dual-channel device, the channel of interest is the one that was previously selected in the Write Mode.
In addition, to read both RDAC values consecutively, users
have to perform two write-read cycles. For example, users may
first specify the RDAC1 subaddress in the Write Mode (it is not
necessary to issue the Data Byte and the STOP condition), then
change to the Read Mode and read the RDAC1 value. To continue reading the RDAC2 value, users have to switch back to
the Write Mode and specify the subaddress, then switch once
again to the Read Mode and read the RDAC2 value. It is not
necessary to issue the Write Mode Data Byte or the first stop
condition for this operation. Users should refer to Figures 2 and
3 for the programming format.
MULTIPLE DEVICES ON ONE BUS
Figure 5 shows four AD5242 devices on the same serial bus.
Each has a different slave address since the state of their AD0
and AD1 Pins are different. This allows each RDAC within
REV. B
IN
1
2
O1 DATA IN FRAME 2
OF WRITE MODE
O1
MN
VSS
Figure 7. Output Stage of Logic Output O1
ADDITIONAL PROGRAMMABLE LOGIC OUTPUT
AD5241/AD5242 feature additional programmable logic outputs, O1 and O2, that can be used to drive digital load, analog
switches, and logic gates. They can also be used as self-contained shutdown as preset to logic 0 feature which will be
explained later. O1 and O2 default to logic 0 during power-up.
The logic states of O1 and O2 can be programmed in Frame 2
under the Write Mode (see Figure 2). Figure 7 shows the output stage of O1 which employs large P and N channel MOSFETs
in push-pull configuration. As shown, the output will be equal to
VDD or VSS, and these logic outputs have adequate current driving
capability to drive milliamperes of load.
–11–
AD5241/AD5242
Users can also activate O1 and O2 in three different ways without affecting the wiper settings.
O1
SHDN
1. Start, Slave Address Byte, Acknowledge, Instruction Byte
with O1 and O2 specified, Acknowledge, Stop.
RPD
2. Complete the write cycle with Stop, then Start, Slave Address
Byte, Acknowledge, Instruction Byte with O1 and O2 specified, Acknowledge, Stop.
SDA
SCL
3. Do not complete the write cycle by not issuing the Stop, then
Start, Slave Address Byte, Acknowledge, Instruction Byte
with O1 and O2 specified, Acknowledge, Stop.
All digital inputs are protected with a series input resistor and
parallel Zener ESD structures shown in Figure 9. This applies
to digital input Pins SDA, SCL, and SHDN.
Figure 8. Shutdown by Internal Logic Output
340
LOGIC
VSS
Figure 9. ESD Protection of Digital Pins
SELF-CONTAINED SHUTDOWN FUNCTION
Shutdown can be activated by strobing the SHDN Pin or programming the SD Bit in the Write Mode Instruction Byte. In
addition, shutdown can even be implemented with the device
digital output as shown in Figure 8. In this configuration, the
device will be shut down during power-up, but users are allowed
to program the device. Thus when O1 is programmed high, the
device will exit from the shutdown mode and respond to the
new setting. This self-contained shutdown function allows absolute shutdown during power-up, which is crucial in hazardous
environments without adding extra components.
–12–
A,B,W
VSS
Figure 10. ESD Protection of Resistor Terminals
REV. B
AD5241/AD5242
Test Circuits
Test Circuits 1 to 9 define the test conditions used in the product
specifications table.
5V
OP279
V+ = VDD
1LSB = V+/2N
DUT
A
V
VIN
W
OFFSET
GND
B
W
A
VMS
DUT
Test Circuit 6. Noninverting Gain
A
NO CONNECT
+15V
W
DUT
VIN
IW
DUT
OP42
W
OFFSET
GND
2.5V
VMS
–15V
Test Circuit 7. Gain vs. Frequency
Test Circuit 2. Resistor Position Nonlinearity Error (Rheostat Operation; R-INL, R-DNL)
RSW =
DUT
VMS2
0.1V
ISW
CODE =
DUT
W
H
W
I W = VDD /R NOMINAL
VW
VOUT
B
B
A
B
OFFSET
BIAS
Test Circuit 1. Potentiometer Divider Nonlinearity Error
(INL, DNL)
A
VOUT
B
0.1V
ISW
B
VMS1
RW = [VMS1 – VMS2]/I W
VSS TO VDD
Test Circuit 8. Incremental ON Resistance
Test Circuit 3. Wiper Resistance
VA
NC
V+ = VDD 10%
VDD
PSRR (dB) = 20 LOG
A
V+
W
PSS (%/%) =
B
VMS%
VMS
( VDD )
VDD
DUT
VDD%
VSS
A
GND
B
VMS
W
ICM
VCM
NC
Test Circuit 9. Common-Mode Leakage Current
Test Circuit 4. Power Supply Sensitivity (PSS, PSRR)
A
DUT
B
5V
W
OP279
OFFSET
GND
VOUT
OFFSET
BIAS
Test Circuit 5. Inverting Gain
REV. B
–13–
AD5241/AD5242
DIGITAL POTENTIOMETER SELECTION GUIDE
Part
Number
Number
of VRs
Terminal
per
Voltage
Package1 Range
Interface
Data
Control2
Nominal
Resistance
(k)
Resolution
(Number
of Wiper
Positions)
Power
Supply
Current
(IDD)
Packages
Comments
AD5201
1
± 3 V, +5.5 V
3-Wire
10, 50
33
40 µA
MSOP-10
Full AC Specs, Dual Supply,
Power-On-Reset, Low Cost
AD5220
1
5.5 V
Up/Down
10, 50, 100
128
40 µA
PDIP, SO-8, MSOP-8
No Rollover, Power-On-Reset
AD7376
1
± 15 V, +28 V
3-Wire
10, 50, 100, 1000
128
100 µA
PDIP-14, SOL-16,
TSSOP-14
Single 28 V or Dual ± 15 V
Supply Operation
AD5200
1
± 3 V, +5.5 V
3-Wire
10, 50
256
40 µA
MSOP-10
Full AC Specs, Dual Supply,
Power-On-Reset
AD8400
1
5.5 V
3-Wire
1, 10, 50, 100
256
5 µA
SOIC-8
Full AC Specs
AD5241
1
± 3 V, +5.5 V
2-Wire
10, 100, 1000
256
50 µA
SOIC-14, TSSOP-14
I2C Compatible, TC
< 50 ppm/°C
AD5231
1
±2.75 V, +5.5 V 3-Wire
10, 50, 100
1024
10 µA
TSSOP-16
Nonvolatile Memory, Direct
Program, I/D, ± 6 dB Settability
AD5260
1
± 5 V, +15 V
3-Wire
20, 50, 200
256
60 µA
TSSOP-14
TC < 50 ppm/°C
AD5207
2
± 3 V, +5.5 V
3-Wire
10, 50, 100
256
40 µA
TSSOP-14
Full AC Specs, SVO
AD5222
2
± 3 V, +5.5 V
Up/Down
10, 50, 100, 1000
128
80 µA
SOIC-14, TSSOP-14
No Rollover, Stereo, Power-OnReset, TC < 50 ppm/°C
AD8402
2
5.5 V
3-Wire
1, 10, 50, 100
256
5 µA
PDIP, SOIC-14,
TSSOP-14
Full AC Specs, nA
Shutdown Current
AD5232
2
±2.75 V, +5.5 V 3-Wire
10, 50, 100
256
10 µA
TSSOP-16
Nonvolatile Memory, Direct
Program, I/D, ± 6 dB Settability
AD5235
2
±2.75 V, +5.5 V 3-Wire
25, 250
1024
5 µA
TSSOP-16
Nonvolatile Memory,
TC < 50 ppm/°C
AD5242
2
± 3 V, +5.5 V
2-Wire
10, 100, 1000
256
50 µA
SOIC-16, TSSOP-16
I2C Compatible, TC
< 50 ppm/°C
AD5262
2
± 5 V, +12 V
3-Wire
20, 50, 200
256
60 µA
TSSOP-16
Medium Voltage Operation,
TC < 50 ppm/°C
AD5203
4
5.5 V
3-Wire
10, 100
64
5 µA
PDIP, SOL-24,
TSSOP-24
Full AC Specs, nA
Shutdown Current
AD5233
4
±2.75 V, +5.5 V 3-Wire
10, 50, 100
64
10 µA
TSSOP-24
Nonvolatile Memory, Direct
Program, I/D, ± 6 dB Settability
AD5204
4
± 3 V, +5.5 V
3-Wire
10, 50, 100
256
60 µA
PDIP, SOL-24,
TSSOP-24
Full AC Specs, Dual Supply,
Power-On-Reset
AD8403
4
5.5 V
3-Wire
1, 10, 50, 100
256
5 µA
PDIP, SOL-24,
TSSOP-24
Full AC Specs, nA
Shutdown Current
AD5206
6
± 3 V, +5.5 V
3-Wire
10, 50, 100
256
60 µA
PDIP, SOL-24,
TSSOP-24
Full AC Specs, Dual Supply,
Power-On-Reset
NOTES
1
VR stands for variable resistor. This term is used interchangeably with RDAC, programmable resistor, and digital potentiometer.
2
3-wire interface is SPI and Microwire compatible. 2-wire interface is I 2C compatible.
–14–
REV. B
AD5241/AD5242
OUTLINE DIMENSIONS
14-Lead Thin Shrink Small Outline Package [TSSOP]
(RU-14)
16-Lead Thin Shrink Small Outline Package [TSSOP]
(RU-16)
Dimensions shown in millimeters
Dimensions shown in millimeters
5.10
5.00
4.90
5.10
5.00
4.90
14
16
8
4.50
4.40
4.30
4.50
4.40
4.30
6.40
BSC
1
8
PIN 1
0.65
BSC
1.20
MAX
COPLANARITY
6.40
BSC
1
7
PIN 1
1.05
1.00
0.80
9
0.15
0.05
0.30
0.19
SEATING
PLANE
0.20
0.09
0.75
0.60
0.45
8
0
COPLANARITY
0.15
0.05
1.20
MAX
0.65
BSC
SEATING
PLANE
0.20
0.09
8
0
COMPLIANT TO JEDEC STANDARDS MO-153AB
COMPLIANT TO JEDEC STANDARDS MO-153AB-1
14-Lead Standard Small Outline Package [SOIC]
Narrow Body
(R-14)
16-Lead Standard Small Outline Package [SOIC]
Narrow Body
(R-16A)
Dimensions shown in millimeters and (inches)
Dimensions shown in millimeters and (inches)
8.75 (0.3445)
8.55 (0.3366)
4.00 (0.1575)
3.80 (0.1496)
PIN 1
0.75
0.60
0.45
10.00 (0.3937)
9.80 (0.3858)
14
8
1
7
1.27 (0.0500)
BSC
1.75 (0.0689)
1.35 (0.0531)
6.20 (0.2441)
5.80 (0.2283)
COPLANARITY
0.25 (0.0098)
0.10 (0.0039)
0.51 (0.0201)
0.33 (0.0130)
SEATING
PLANE
4.00 (0.1575)
3.80 (0.1496)
16
9
1
8
6.20 (0.2441)
5.80 (0.2283)
PIN 1 1.27 (0.0500) 1.75 (0.0689)
0.50 (0.0197)
45
BSC
1.35 (0.0531)
0.25 (0.0098)
COPLANARITY
0.25 (0.0098)
0.10 (0.0039)
8
0.51 (0.0201) SEATING
0.25 (0.0098) 0 1.27 (0.0500)
PLANE
0.33 (0.0130)
0.40 (0.0157)
0.19 (0.0075)
0.50 (0.0197)
45
0.25 (0.0098)
8
0.25 (0.0098) 0 1.27 (0.0500)
0.40 (0.0157)
0.19 (0.0075)
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN
CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS
(IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN
COMPLIANT TO JEDEC STANDARDS MS-012 AB
COMPLIANT TO JEDEC STANDARDS MS-012 AC
REV. B
–15–
AD5241/AD5242
Revision History
Location
Page
8/02—Data Sheet changed from REV. A to REV. B.
Changes to GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Changes to SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Changes to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Additions to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Changes to TPC 8 and TPC 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
C00926–0–8/02(B)
Additions to FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Changes to READBACK RDAC VALUE section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Changes to ADDITIONAL PROGRAMMABLE LOGIC OUTPUT section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Added SELF-CONTAINED SHUTDOWN section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Added new Figure 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Changes to DIGITAL POTENTIOMETER SELECTION GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2/02—Data Sheet changed from REV. 0 to REV. A.
Edits to FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Edits to FUNCTIONAL BLOCK DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Edits to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Changes to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Edits to PIN FUNCTION DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Edits to Figures 1, 2, 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Addition of Readback RDAC Value and Additional Programmable Logic Output sections, and addition of new Figure 7
(which changed succeeding figure numbers) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
PRINTED IN U.S.A.
Additions/edits to DIGITAL POTENTIOMETER SELECTION GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
–16–
REV. B