Single/Dual, +15 V/±5 V, 256-Position,
I2C-Compatible Digital Potentiometer
AD5280/AD5282
Rev. C
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibilityis assumedbyAnalogDevicesforitsuse,norforanyinfringementsof patentsorother
rightsofthirdpartiesthatmayresultfromitsuse.Specificationssubjecttochangewithoutnotice.No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarksandregisteredtrademarksarethepropertyoftheirrespectiveowners.
One Te
U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
2002–2009 Analog Devices, Inc. All rights reserved.
chnology Way, P.O. Box 9106, Norwood, MA 02062-9106,
FEATURES
AD5280: 1 channel
AD5282: 2 channels
256 positions
+10 V to +15 V single supply; ±5.5 V dual-supply operation
Fixed terminal resistance: 20 kΩ, 50 kΩ, 200 kΩ
Low temperature coefficient: 30 ppm/°C
Power-on midscale preset1 Programmable reset
Operating temperature: 40oC to +85oC
I2C-compatible interface
APPLICATIONS
Multimedia, video, and audio
Communications
Mechanical potentiometer replacement
Instrumentation: gain, offset adjustment
Programmable voltage source
Programmable current source
Line impedance matching
GENERAL DESCRIPTION
The AD5280/AD5282 are single-channel and dual-channel,
256-position, digitally controlled variable resistors (VRs)
2.
The 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. The
fixed A-to-B terminal resistance of 20 kΩ, 50 kΩ, or 200 kΩ has
a 1% channel-to-channel matching tolerance. The nominal
temperature coefficient of both parts is 30 parts per million/
degrees centigrade (ppm/°C). Another key feature is that the
parts can operate up to +15 V or ±5 V.
Wiper position programming defaults to midscale at system
power-on. When powered, the VR wiper position is programmed
by an I2C-compatible, 2-wire serial data interface. The AD5280/
AD5282 feature sleep mode programmability. This allows any
level of preset in power-up and is an alternative to a costly
EEPROM solution. Both parts have additional programmable
logic outputs that enable users to drive digital loads, logic gates,
LED drivers, and analog switches in their system.
1 Assert shutdown and program the device during power-up, then deassert
the shutdown to achieve the desired preset level.
2 The terms digital potentiometer, VR, and RDAC are used interchangeably.
The AD5280/AD5282 are available in thin, surface-mounted
14-lead TSSOP and 16-lead TSSOP. All parts are guaranteed to
operate over the extended industrial temperature range of
40°C to +85°C. For 3-wire SPI-compatible interface applica-
www.analog.com.
FUNCTIONAL BLOCK DIAGRAMS
A
WB
O1
O2
RDAC REGISTER
OUTPUT REGISTER
SERIAL INPUT REGISTER
AD5280
SHDN
VDD
VSS
SDA
SCL
GND
AD0
AD1
ADDRESS
CODE
PWR ON
RESET
VL
8
02
92
9-
07
0
Figure 1. AD5280
A1
W1
B1
O1
RDAC1 REGISTER
RDAC2 REGISTER
OUTPUT
REGISTER
SERIAL INPUT REGISTER
AD5282
SHDN
VDD
SDA
SCL
GND
AD0
AD1
A2
W2
B2
ADDRESS
CODE
PWR ON
RESET
8
02
92
9-
0
1
VDD
VSS
VL
Figure 2. AD5282