Analog Devices Inc. AD5242BRU1M

Overview

AD5242BRU1M from Analog Devices is a dual-channel, I²C-compatible 256-position digital potentiometer with 1 MΩ end-to-end resistance, 30 ppm/°C temperature coefficient, and operation from 2.7 V to 5.5 V single supply or ±2.7 V dual supply. It replaces mechanical potentiometers in precision gain/offset adjustment circuits where channel-to-channel matching (±1%) and stable voltage-divider ratio accuracy are required.

For engineers reviewing the AD5242BRU1M datasheet, AD5242BRU1M pinout, AD5242BRU1M application, or AD5242BRU1M equivalent, key selection criteria include dual-channel 1 MΩ rheostat/potentiometer configuration, programmable logic outputs O1/O2, shutdown functionality via SHDN pin or SD bit, and guaranteed −40°C to +105°C operation in TSSOP-16 package.

Technical Context

The AD5242BRU1M implements two independent 8-bit digitally controlled resistor ladders, each with 256 tap points and fixed 1 MΩ A–B resistance. Its I²C interface supports up to 4 devices on one bus using AD0/AD1 address pins, and includes readback capability for both RDAC registers.

It features dual programmable logic outputs (O1, O2) driven by push-pull MOSFET stages capable of sourcing/sinking ≥1.6 mA, plus an active-low SHDN pin that shorts W to B while opening A - preserving register contents during low-power mode.

Key Specifications

Pinout & Package

AD5242BRU1M is housed in a 16-lead TSSOP package (4.4 mm × 5.0 mm, 0.65 mm pitch), optimized for space-constrained industrial and instrumentation PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital potentiometer applications.

Compared with AD5242BRU100 and MCP42100-I/SL, the AD5242BRU1M uniquely combines 1 MΩ resistance, dual-channel matching, I²C readback, and 5 ppm/°C voltage-divider tempco - making it optimal for high-precision, ratiometric, and thermally stable applications where impedance level and tracking are critical.

Availability

AD5242BRU1M is available at Aetrix Electronics and suitable for industrial instrumentation, audio equipment, sensor signal conditioning, and fieldbus interface designs requiring stable component supply across extended temperature and long production lifecycles.

Supply support for AD5242BRU1M includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets since 1965.

The AD5242BRU1M belongs to the AD5241/AD5242 family of I²C-compatible digital potentiometers designed specifically for replacing mechanical trimmers in precision analog systems where reliability, temperature stability, and programmability are essential.

FAQ

What is the maximum operating temperature range for the AD5242BRU1M?

The AD5242BRU1M is fully specified and guaranteed to operate from −40°C to +105°C. This extended temperature range is validated across all electrical parameters including resistance tolerance, tempco, and I²C timing, making it suitable for under-hood automotive modules and industrial control cabinets without derating.

Does the AD5242BRU1M support dual-supply operation, and what are the limits?

Yes, the AD5242BRU1M supports true dual-supply operation with VDD = +2.7 V and VSS = −2.7 V (±2.7 V). The absolute maximum rating allows VDD to VSS ≤ 7 V, and resistor terminals (A, B, W) tolerate voltages from VSS to VDD - enabling ac-coupled and bipolar signal conditioning applications not possible with single-supply-only digital pots.

How does the AD5242BRU1M handle power-on initialization?

The AD5242BRU1M features an internal power-on reset circuit that automatically loads code 0x80 (midscale) into both RDAC registers at power-up. This behavior is independent of I²C activity and ensures a known, safe resistance state (500 kΩ per channel) without requiring host firmware initialization - critical for fail-safe analog subsystems.

Can both channels of the AD5242BRU1M be updated simultaneously via I²C?

No - the AD5242BRU1M requires sequential updates: the A/B bit in the instruction byte selects either RDAC1 (A/B = 0) or RDAC2 (A/B = 1), and only the selected channel is written or read per transaction. Simultaneous update is not supported; however, back-to-back writes with identical instruction bytes (only changing data) minimize latency between channel settings.

What is the purpose of the O1 and O2 pins on the AD5242BRU1M?

The O1 and O2 pins are programmable logic outputs controlled via bits in the I²C instruction byte. Each can be independently set to logic high (VDD/VSS rail) or low, sourcing/sinking ≥1.6 mA. They eliminate external GPIOs for tasks like enabling LED status indicators, gating analog switches, or synchronizing auxiliary circuitry - all while sharing the same I²C bus and timing as the potentiometer control.