64-Position Up/Down

Control Digital Potentiometer

AD5227

Rev. B

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FEATURES

64-position digital potentiometer

10 kΩ, 50 kΩ, 100 kΩ end-to-end terminal resistance

Simple up/down digital or manual configurable control

Midscale preset

Low potentiometer mode tempco = 10 ppm/°C

Low rheostat mode tempco = 35 ppm/°C

Fast adjustment time, ts = 1 μs

Chip select enable multiple device operation

Low operating voltage, 2.7 V to 5.5 V

Automotive temperature range, −40°C to +105°C

Compact thin SOT-23-8 (2.9 mm × 3 mm) Pb-free package

APPLICATIONS

Mechanical potentiometer and trimmer replacements

LCD backlight, contrast, and brightness controls

Portable electronics level adjustment

Programmable power supply

Digital trimmer replacements

Automatic closed-loop control

FUNCTIONAL BLOCK DIAGRAM

CS

U/D

CLK

GND

6-BIT UP/DOWN

CONTROL

LOGIC

POR

MIDSCALE

WIPER

REGISTER

A

W

B

AD5227

Figure 1.

GENERAL DESCRIPTION

The AD5227 is Analog Devices’ latest 64-step up/down control

adjustment function as a 5 V potentiometer or variable resistor.

Its simple 3-wire up/down interface allows manual switching or

high speed digital control. The AD5227 presets to midscale at

power-up. When CS is enabled, the devices changes step at

every clock pulse. The direction is determined by the state of

the U/D pin (see

). The interface is simple to activate by

any host controller, discrete logic, or manually with a rotary

encoder or pushbuttons. The AD5227’s 64-step resolution, small

footprint, and simple interface enable it to replace mechanical

potentiometers and trimmers with typically 6× improved

resolution, solid-state reliability, and design layout flexibility,

resulting in a considerable cost savings in end users’ systems.

Table 1

The AD5227 is available in a compact thin SOT-23-8 (TSOT-8)

Pb-free package. The part is guaranteed to operate over the

automotive temperature range of −40°C to +105°C.

Users who consider EEMEM potentiometers should refer to

some recommendations in the Applications section.

Table 1. Truth Table

CS

CLK

U/D

Operation1

0

↓

0

0

↓

1

1

X

X

No Operation