AD5228 Datasheet | Analog Devices

Data Sheet 32-Position Manual Up/Down Control Potentiometer AD5228 Features 32-position digital potentiometer 10 kΩ, 50 kΩ, 100 kΩ end-to-end terminal resistance Simple manual up/down control Self-contained, requires only 2 pushbutton tactile switches Built-in adaptive debouncer Discrete step-up/step-down control Autoscan up/down control with 4 steps per second Pin-selectable zero-scale/midscale preset Low potentiometer mode tempco, 5 ppm/°C Low rheostat mode tempco, 35 ppm/°C Digital control patible Ultralow power, IDD = 0.4 µA typ and 3 µA max Low operating voltage, 2.7 V to 5.5 V Temperature range, - 40°C to +105°C pact thin SOT-23-8 (2.9 mm × 3 mm) Pb-free package APPLICATIONS Mechanical potentiometer and trimmer replacements LCD backlight, contrast, and brightness controls Digital volume control Portable device-level adjustments Electronic front panel-level controls Programmable power supply GENERAL DESCRIPTION The AD5228 is Analog Devices’ latest 32-step-up/step-down control digital potentiometer emulating mechanical potentiometer operation1. Its simple up/down control interface allows manual control with just two external pushbutton tactile switches. The AD5228 is designed with a built-in adaptive debouncer that ignores invalid bounces due to contact bounce monly found in mechanical switches. The debouncer is adaptive, acmodating a variety of pushbutton tactile switches that generally have less than 10 ms of bounce time during contact closures. When choosing the switch, the user should consult the timing specification of the switch to ensure its suitability in an AD5228 application. 1 The terms digital potentiometer and RDAC are used interchangeably. FUNCTIONAL BLOCK DIAGRAM PUSH-UP BUTTON PU PD PUSH-DOWN BUTTON UP/DOWN CONTROL LOGIC R1 R2 D AD5228 DISCRETE STEP/AUTO SCAN DETECT 04422-0-001 ADAPTIVE DEBOUNCER ZERO- OR MIDSCALE PRESET Figure 1. The AD5228 can increment or decrement the resistance...