Analog Devices Inc. ADR425BR

Overview

ADR425BR from Analog Devices is an ultraprecision XFET® voltage reference delivering a stable 5.000 V output with ±2 mV initial accuracy (B grade), 3 ppm/°C max temperature coefficient, 3.4 μV p-p (0.1 Hz to 10 Hz) low-frequency noise, and 10 mA output current capability. It operates from 7 V to 18 V supply and supports precision data acquisition in high-resolution ADC/DAC systems requiring metrology-grade stability.

For engineers reviewing the ADR425BR datasheet, ADR425BR pinout, ADR425BR application, or ADR425BR equivalent, this page delivers verified specifications, SOIC/MSOP package mapping, trim-adjustable architecture details, and real-world design context for optical network control, portable medical instrumentation, and industrial process monitoring circuits.

Technical Context

The ADR425BR uses patented XFET® technology-based on two matched JFETs with differential pinch-off voltage-to generate a ~0.5 V intrinsic reference, then applies PTAT-based curvature correction for ultra-low 3 ppm/°C drift. Its architecture avoids buried Zener complexity while achieving lower power and superior thermal hysteresis (40 ppm typical) versus band gap alternatives.

It features a dedicated TRIM pin enabling ±0.5% output adjustment without degrading temperature coefficient or long-term stability, and integrates internal circuitry optimized for operation across −40°C to +125°C with only 50 ppm/1000 hours long-term drift. Input headroom is fixed at ≥2 V, and load regulation remains ≤70 ppm/mA up to 10 mA.

Key Specifications

Pinout & Package

ADR425BR is available in both 8-lead SOIC (R) and 8-lead MSOP (RM) packages. Both share identical pinout and thermal characteristics (θJA = 130°C/W for SOIC, 190°C/W for MSOP).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultraprecision voltage reference applications.

Compared with REF5050IDR and LT6655IMS5-5, the ADR425BR uniquely balances 3.4 μV p-p noise, 10 mA drive, 500 μA IQ, and dual SOIC/MSOP packaging-making it optimal for space-constrained, low-power, high-accuracy industrial and medical converters where all four parameters are simultaneously critical.

Availability

ADR425BR is available at Aetrix Electronics and suitable for precision data acquisition systems, portable medical instruments, and industrial process control systems requiring stable component supply with guaranteed long-term availability and traceable lot-level documentation.

Supply support for ADR425BR 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, with R&D and manufacturing operations worldwide.

The ADR42x family-including ADR425BR-is designed specifically for ultraprecision voltage reference applications demanding low noise, exceptional thermal stability, and long-term reliability in test & measurement, medical, and industrial instrumentation.

FAQ

What is the maximum load current supported by the ADR425BR?

The ADR425BR supports up to 10 mA of continuous output current while maintaining specified load regulation of ≤70 ppm/mA across −40°C to +125°C. This enables direct driving of multiple op-amp reference buffers or high-resolution ADC reference inputs without external gain stages. Exceeding 10 mA risks violating output accuracy specs and increasing thermal drift; always verify junction temperature using PD × θJA + TA under actual operating conditions.

Can the ADR425BR operate from a 5 V supply rail?

No-the ADR425BR requires a minimum supply voltage of 7 V to ensure ≥2 V headroom above its 5.000 V output, as specified in the Absolute Maximum Ratings and Electrical Specifications tables. Attempting operation below 7 V results in dropout and unregulated output. For 5 V systems, consider the ADR421 (2.5 V output) or ADR423 (3.0 V output), both rated for lower VIN minima.

How does the TRIM pin on the ADR425BR function in practice?

The TRIM pin on the ADR425BR allows ±0.5% adjustment of the output voltage using an external resistor divider connected between VOUT and GND, with the wiper feeding TRIM. This tuning does not degrade temperature coefficient, long-term stability, or noise performance. Typical implementation uses a 10 kΩ potentiometer; full-scale adjustment range is ±25 mV around 5.000 V, enabling final-system calibration after soldering and layout effects.

Is an output capacitor required for stability with the ADR425BR?

No-ADR425BR is internally compensated and remains stable under all load conditions from 0 mA to 10 mA without any output capacitor. A 0.1 μF ceramic capacitor may be added to reduce broadband noise, and larger values (1–10 μF) improve load transient response, but they increase turn-on settling time. Unlike many references, instability or oscillation is not a risk with or without COUT.

What package options are available for the ADR425BR, and how do their thermal characteristics differ?

The ADR425BR is offered in both 8-lead SOIC (R) and 8-lead MSOP (RM) packages. SOIC has θJA = 130°C/W and θJC = 43°C/W; MSOP has θJA = 190°C/W and θJC = 44°C/W. While MSOP saves 30% board area, its higher θJA means greater junction temperature rise at the same power dissipation-requiring careful thermal layout (e.g., thermal vias, copper pour) in high-ambient or high-load applications.