Single Channel, 1% Resistor tolerance,
1024/256-Position Digital Variable Resistor
Preliminary Technical Data
AD5270/AD5271
FUNCTIONAL BLOCK DIAGRAM
FEATURES
Single-channel, 1,024/256-position resolution
20 kΩ, 50 kΩ and 100 kΩ nominal resistance
Calibrated 1% Nominal Resistor Tolerance
Multiple-time programmable set-and-forget resistance
setting allows 50 time permanent programming
Rheostat mode temperature coefficient: 35 ppm/°C
2.7V to 5.5V single-supply operation
2.5V to 2.75V dual-supply operation for AC or Bipolar
Operations
SPI compatible interface
Wiper setting readback
Power-on refreshed from 50-TP memory
Thin LFCSP(SON)-10 (3 mm x 3 mm x 0.8 mm) package
Compact MSOP-10 (3 mm × 4.9 mm x 1.1mm) package
APPLICATIONS
Mechanical potentiometer replacement
Instrumentation: gain, offset adjustment
Programmable voltage to current conversion
Programmable filters, delays, time constants
Programmable power supply
Figure 1. Block Diagram
Sensor calibration
the SPI compatible digital interface. Unlimited adjustments are
allowed before programming the resistance value into the 50-
TP (Fifty Time Programmable) memory. The AD5270/1 do not
require any external voltage supply to facilitate fuse blow and
there are 50 opportunities for permanent programming. During
50-TP activation, a permanent blow fuse command freezes the
wiper position (analogous to placing epoxy on a mechanical
trimmer).
GENERAL DESCRIPTION
The AD5270/1 are single-channel, 1024/256-positions digitally
controlled resistors1 with less than 1% end-to-end Resistor
Tolerance error and 50-Time Programmable Memory. The
AD5270/1 perform the same electronic adjustment function as
a mechanical rheostat with enhanced resolution, solid state
reliability, and superior low temperature coefficient perform-
ance.
The AD5270/1 offer guaranteed industry leading low resistor
tolerance errors of 1% with a nominal temperature coefficient
of 35 ppm/ºC. The low resistor tolerance feature simplifies
open-loop applications as well as precision calibration and
tolerance matching applications
The AD5270 and AD5271 are available in a thin 3mmX3mm
LFCSP package and in a compact 10ld MSOP package. The
parts are guaranteed to operate over the extended industrial
temperature range of −40°C to +105°C.
1 The terms programmable resistor and RDAC are used interchangeably.
The AD5270/1 device wiper settings are controllable through
Rev. PrA
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