Analog Devices Inc./Maxim Integrated MAX6126AASA25+

Overview

MAX6126AASA25+ from Maxim Integrated is an ultra-high-precision, ultra-low-noise series voltage reference delivering 2.500V output with ±0.02% (max) initial accuracy, 3ppm/°C (max) temperature coefficient over –40°C to +125°C, and 1.45μV_P-P (0.1Hz–10Hz) flicker noise. It operates from 3.0V to 12.6V supply, supports ±10mA load current, and enables remote sensing via separate force (OUTF) and sense (OUTS) outputs - ideal for high-resolution ADC/DAC biasing in test equipment and industrial control.

For engineers reviewing the MAX6126AASA25+ datasheet, MAX6126AASA25+ pinout, MAX6126AASA25+ application, or MAX6126AASA25+ equivalent, key selection criteria include its 200mV (max) dropout voltage at 10mA, 380μA quiescent current, 0.1μF–10μF capacitive-load stability, and Kelvin-sensing capability for sub-25μV/mA load regulation error in precision metrology systems.

Technical Context

The MAX6126AASA25+ employs curvature-corrected bandgap architecture with laser-trimmed thin-film resistors to achieve 3ppm/°C max tempco and ±0.02% initial accuracy. Its proprietary low-noise design separates noise-sensitive reference core from output buffer, enabling 1.45μV_P-P (0.1Hz–10Hz) and 75nV/√Hz (1kHz, no NR cap) without elevated supply current.

It implements true 4-terminal Kelvin sensing: OUTF supplies load current while OUTS and GNDS form a high-impedance feedback path to regulate voltage at the load node, eliminating IR drop errors in long traces or PCB copper resistance. The NR pin accepts a 0.1μF capacitor to reduce wideband noise to 45nV/√Hz and 0.9μV_P-P (0.1Hz–10Hz).

Key Specifications

Pinout & Package

MAX6126AASA25+ is housed in an 8-pin SO package (SOIC-8), RoHS-compliant, with exposed pad for thermal performance. Pin 1 is NR (Noise Reduction), Pin 2 is IN, Pin 3 is GND, Pin 4 is GNDS, Pins 5 & 8 are internally connected (NC), Pin 6 is OUTS, and Pin 7 is OUTF.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADR4525BRZ and REF5025IDR, MAX6126AASA25+ uniquely combines Kelvin force/sense outputs, 0.1μF–10μF stability, and NR-capable noise reduction - making it the only option for sub-10μV/mA load regulation and <1μV_P-P flicker noise in compact, high-accuracy systems.

Availability

MAX6126AASA25+ is available at Aetrix Electronics and suitable for high-resolution A/D converters, automated test equipment, and digital voltmeters requiring stable component supply with guaranteed automotive-grade (-40°C to +125°C) performance and long-term calibration integrity.

Supply support for MAX6126AASA25+ 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

Maxim Integrated (now part of Analog Devices) designs high-performance analog and mixed-signal ICs for precision, power, and interface applications - with emphasis on reliability, low noise, and automotive qualification.

The MAX6126 family delivers ultra-stable voltage references for metrology-grade systems, targeting applications demanding <±0.02% accuracy, <3ppm/°C tempco, and sub-2μV_P-P flicker noise in harsh thermal environments.

FAQ

What is the maximum load current supported by MAX6126AASA25+ while maintaining specified accuracy?

MAX6126AASA25+ supports ±10mA sink/source current with guaranteed load regulation error ≤25μV/mA. At ±10mA, total output voltage shift remains ≤±250μV - well within its ±0.02% (±500μV) initial accuracy band. This enables direct drive of op-amp inputs, ADC references, and precision current sources without external buffers.

Can MAX6126AASA25+ operate from a 2.7V supply?

No - MAX6126AASA25+ requires minimum 3.0V supply per its 2.5V output specification (V_IN ≥ V_OUT + 200mV). While the general MAX6126 family supports 2.7V for 2.048V variants, the 2.500V version (MAX6126AASA25+) specifies 3.0V to 12.6V input range to ensure full accuracy and noise performance across temperature.

How does the NR pin improve noise performance in MAX6126AASA25+?

The NR pin on MAX6126AASA25+ accepts a 0.1μF capacitor to reduce 1kHz wideband noise from 75nV/√Hz to 45nV/√Hz and 0.1Hz–10Hz flicker noise from 1.45μV_P-P to 0.9μV_P-P. This external RC filter suppresses internal amplifier noise without increasing quiescent current - a key differentiator versus conventional low-noise references.

What is the purpose of separate OUTF and OUTS pins on MAX6126AASA25+?

OUTF delivers load current while OUTS provides high-impedance feedback to the internal regulator - enabling true 4-wire Kelvin sensing. When paired with GNDS, this configuration cancels voltage drop across PCB traces and connectors, achieving <±25μV/mA load regulation error even with 100mΩ path resistance - critical for metrology-grade accuracy.

Is MAX6126AASA25+ qualified for automotive applications?

Yes - MAX6126AASA25+ is rated for the full automotive temperature range (–40°C to +125°C), features AEC-Q100 stress testing compliance, and guarantees 3ppm/°C max tempco and ±0.02% initial accuracy across that range. Its SO package with exposed pad also supports enhanced thermal dissipation required in under-hood modules.