256-Position, Ultralow Power
1.8 V Logic-Level Digital Potentiometer
AD5165
FEATURES
Ultralow standby power IDD = 50 nA typical
FUNCTIONAL BLOCK DIAGRAM
V
DD
256-position
End-to-end resistance 100 kΩ
Logic high voltage 1.8 V
Power supply 2.7 V to 5.5 V
Low temperature coefficient 35 ppm/°C
Compact thin 8-lead TSOT-8 (2.9 mm × 2.8 mm) package
Simple 3-wire digital interface
A
CS
3-WIRE
INTERFACE
SDI
W
B
CLK
WIPER
REGISTER
Wide operating temperature −40°C to +125°C
Pin-to-pin compatible to AD5160 with CS inverted
GND
APPLICATIONS
Figure 1.
Battery-operated electronics adjustment
Remote utilities meter adjustment
Mechanical potentiometer replacement
Transducer circuit adjustment
Automotive electronics adjustment
Gain control and offset adjustment
System calibration
PIN CONFIGURATION
1
2
3
4
W
8
7
6
5
A
V
AD5165
TOP VIEW
(Not to Scale)
B
DD
CS
GND
CLK
SDI
VCXO adjustment
Figure 2.
GENERAL OVERVIEW
The AD5165 provides a compact 2.9 mm × 2.8 mm packaged
solution for 256-position adjustment applications. These devices
perform the same electronic adjustment function as mechanical
potentiometers or variable resistors, with enhanced resolution,
solid-state reliability, and superior low temperature coefficient
performance. The AD5165’s supply voltage requirement is 2.7 V
to 5.5 V, but its logic voltage requirement is 1.8 V to VDD. The
AD5165 consumes very low quiescent power during standby
mode and is ideal for battery-operated applications.
TYPICAL APPLICATION
5V
V
= 1.8V MIN
OH
V
DD
3.3V
V
A
AD5165
WIDE TERMINAL
V
W
VOLTAGE RANGE:
DIGITAL
CONTROL
LOGIC OR
MICRO
CS
V
B
0V < V ,V ,V < 5V
A B W
CLK
SDI
Wiper settings are controlled through a simple 3-wire interface.
The interface is similar to the SPI® digital interface except for the
inverted chip-select function that minimizes logic power con-
sumption in the idling state. The resistance between the wiper
and either endpoint of the fixed resistor varies linearly with
respect to the digital code transferred into the wiper register.
GND
Figure 3.
Note:
Operating from a 2.7 V to 5.5 V power supply and consuming
less than 50 nA typical standby power allows use in battery-
operated portable or remote utility device applications.
The terms digital potentiometer, RDAC, and VR are used interchangeably.
Rev. 0
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