Analog Devices Inc. AD5291BRUZ-50-RL7

Overview

AD5291BRUZ-50-RL7 from Analog Devices is a single-channel, 256-position digital potentiometer with 50 kΩ nominal resistance, ±1% end-to-end resistor tolerance in resistor performance mode, 20-times programmable nonvolatile memory, and SPI interface. It operates from +9 V to +33 V single supply or ±9 V to ±16.5 V dual supply, and is rated for −40°C to +105°C. It replaces mechanical potentiometers in precision gain/offset calibration circuits.

For engineers reviewing the AD5291BRUZ-50-RL7 datasheet, AD5291BRUZ-50-RL7 pinout, AD5291BRUZ-50-RL7 application, or AD5291BRUZ-50-RL7 equivalent, key selection criteria include guaranteed ±1% RAB tolerance in R-Perf mode, 35 ppm/°C rheostat tempco, wiper readback capability, 14-lead TSSOP package compatibility, and 20-TP memory retention without external programming voltage.

Technical Context

The AD5291BRUZ-50-RL7 implements a digitally controlled variable resistor using a segmented thin-film resistor ladder with CMOS switch matrix, supporting both rheostat (A–W or W–B) and potentiometer (A–W–B) configurations. Its 20-TP memory uses fuse-based OTP storage, enabling permanent wiper position retention after up to 20 programming cycles.

It features dual-mode operation: normal mode (±7% RAB tolerance, 8-bit resolution) and resistor performance mode (±1% RAB tolerance, restricted code range per Table 3), with separate temperature coefficients-35 ppm/°C for rheostat use and 5 ppm/°C for voltage divider applications. The SPI interface supports 50 MHz clocking, readback, and daisy-chain capability via SDO.

Key Specifications

Pinout & Package

AD5291BRUZ-50-RL7 is housed in a 14-lead TSSOP package (4.4 mm × 5.0 mm, 0.65 mm pitch), optimized for high-density PCB layouts and industrial thermal environments (−40°C to +105°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5291BRUZ-50-RL7, AD5292BRUZ-50-RL7 offers higher resolution at identical accuracy and memory endurance, while MAX5487ETE+T trades guaranteed tolerance and programmability for lower cost and simpler interface-making AD5291BRUZ-50-RL7 optimal for industrial calibration requiring both precision and field reprogrammability.

Availability

AD5291BRUZ-50-RL7 is available at Aetrix Electronics and suitable for instrumentation gain calibration, programmable power supply setpoint control, and sensor offset adjustment requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for AD5291BRUZ-50-RL7 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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD5291/AD5292 family was designed specifically for high-accuracy, high-voltage industrial calibration and trimming-emphasizing guaranteed resistor tolerance, nonvolatile memory endurance, and wide supply flexibility over generic digital potentiometer use cases.

FAQ

What is the guaranteed end-to-end resistance tolerance for AD5291BRUZ-50-RL7?

The AD5291BRUZ-50-RL7 guarantees ±1% nominal resistor tolerance in resistor performance mode, validated across −40°C to +105°C and confirmed in Table 1 of the datasheet. This applies specifically to the 50 kΩ version and requires operation within defined code ranges per Table 3. In normal mode, tolerance degrades to ±7%. The ±1% spec enables open-loop calibration without post-manufacturing trimming.

Does AD5291BRUZ-50-RL7 support dual-supply operation?

Yes, AD5291BRUZ-50-RL7 supports true dual-supply operation from ±9 V to ±16.5 V, allowing ground-referenced bipolar signal adjustment. Terminal A, B, and W have no polarity restrictions relative to each other, enabling configurations such as AC-coupled gain control or bidirectional current setting. The analog core remains functional with VSS negative and VDD positive, while VLOGIC (2.7 V to 5.5 V) operates independently.

How many times can the 20-TP memory of AD5291BRUZ-50-RL7 be programmed?

The 20-TP memory of AD5291BRUZ-50-RL7 supports exactly 20 permanent programming cycles-each cycle irreversibly blows a fuse to lock the wiper position. Unlimited volatile adjustments are allowed before committing to memory. Programming requires no external high-voltage supply; the internal charge pump generates necessary voltage using the EXT_CAP capacitor. After 20 cycles, further writes to memory are disabled.

What is the temperature coefficient of AD5291BRUZ-50-RL7 in voltage divider mode?

In voltage divider (potentiometer) mode, AD5291BRUZ-50-RL7 exhibits a guaranteed 5 ppm/°C temperature coefficient for the voltage division ratio, measured at half-scale code and specified in Table 1. This ensures minimal gain drift in feedback networks of precision amplifiers. By contrast, rheostat mode has a higher 35 ppm/°C tempco-confirming the device's optimization for divider-based applications requiring ultra-stable ratios.

Can AD5291BRUZ-50-RL7 wiper position be read back via SPI?

Yes, AD5291BRUZ-50-RL7 supports full wiper position readback via its SPI interface: the 8-bit code is returned on SDO during a dedicated read command. This enables closed-loop verification, fault detection (e.g., detecting unintended wiper movement), and diagnostic logging. Readback executes in ≤450 ns, and the RDY pin signals completion. The feature is fully supported in both normal and resistor performance modes.