AD8402AR100

Overview

The AD8402AR100 is a dual-channel, 256-position digitally controlled variable resistor (VR) from Analog Devices. It operates on a single 2.7 V to 5.5 V supply and features an SPI-compatible 3-wire serial interface for data loading at rates up to 10 MHz. The device provides two independent variable resistors with a nominal resistance of 100 kΩ and a linear taper. Each channel includes a volatile latch to maintain the programmed resistance value. Key electrical characteristics include a typical wiper resistance of 200 Ω at 3 V operation and a temperature coefficient of 500 ppm/°C. The component supports power shutdown modes with current consumption below 5 μA.

Feature Summary

• Dual-channel architecture with 256 programmable positions per channel
• SPI-compatible 3-wire serial interface supporting 10 MHz update rates
• Nominal resistance of 100 kΩ with ±1% channel-to-channel matching tolerance
• Power shutdown capability reducing supply current to less than 5 μA

Applications

• Mechanical potentiometer replacement in industrial systems
• Programmable filters, delays, and time constant adjustments
• Line impedance matching circuits
• Power supply voltage adjustment controls

Procurement Notes

Verify the specific package type and suffix requirements against the manufacturer's ordering guide, as the AD8402 family is available in multiple configurations including SOIC-14 and PDIP-14. Confirm that the selected variant meets the required thermal and environmental specifications for the intended application environment before finalizing procurement.

Selection Notes

Select the AD8402AR100 when a dual-channel digital solution with 100 kΩ nominal resistance is required. Ensure the system design accommodates the volatile memory nature of the latches, which lose settings upon power loss unless backed up. Verify that the serial interface timing constraints align with the microcontroller or DSP driving the SDI, CLK, and CS pins.

Part Context

The AD8402AR100 belongs to the AD8400/AD8402/AD8403 family of digital potentiometers. While the AD8400 offers a single channel and the AD8403 provides four channels, the AD8402 specifically addresses applications requiring two independent variable resistors in a compact form factor. This family replaces mechanical components in space-constrained designs.

Replacement Considerations

Direct functional replacements within the same family include the AD8402AN100 for through-hole DIP packaging or the AD8402ARUZ100 for thin TSSOP packaging. When substituting, verify that the pinout compatibility remains consistent between the SOIC-14 and alternative packages to ensure PCB layout integrity.