Analog Devices Inc./Maxim Integrated MAX6325ESA

Overview

MAX6325ESA from Maxim Integrated is a precision 2.5V voltage reference IC using buried-zener technology, delivering ±0.02% initial accuracy, 1.5ppm/°C max temperature coefficient (–40°C to +85°C), and 1.5µV_p-p (0.1Hz–10Hz) output noise - designed for high-resolution ADC/DAC biasing in test equipment and industrial control systems.

For engineers reviewing the MAX6325ESA datasheet, MAX6325ESA pinout, MAX6325ESA application, or MAX6325ESA equivalent, key selection criteria include low-noise performance under capacitive loads, ±15mA source/sink capability, external trim support, and SO-8 package compatibility with legacy 8-pin reference layouts.

Technical Context

The MAX6325ESA implements a temperature-compensated buried-zener core with internal curvature correction, achieving near-zero thermal hysteresis (≤8ppm) and stable operation across 8V–36V input range. Its output stage supports sourcing and sinking up to ±15mA while maintaining <30ppm/1000hr long-term stability.

It features dedicated NR (noise reduction) and TRIM pins enabling 1µF capacitor-based wideband noise filtering and ±1% output adjustment without degrading temperature coefficient - both functions validated across its full –40°C to +85°C operating range.

Key Specifications

Pinout & Package

MAX6325ESA is housed in an 8-pin SO (Small Outline) package compliant with JEDEC MS-012, with 1.27mm pitch and exposed pad not present. Pins 1, 7, and 8 are internally connected and must remain unconnected on PCB.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADR441BRZ and REF5025IDR, the MAX6325ESA provides superior noise performance and higher output current in the same SO-8 package - making it the preferred choice for 16-bit data converters operating across extended industrial temperatures without added buffering or thermal compensation.

Availability

MAX6325ESA is available at Aetrix Electronics and suitable for high-resolution analog-to-digital converters, digital voltmeters, and industrial process controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6325ESA 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.

The MAX6325ESA belongs to Maxim's precision voltage reference product line, engineered specifically for metrology-grade accuracy in data conversion, instrumentation, and automated test systems where low noise and temperature stability are non-negotiable.

FAQ

What is the maximum operating temperature range for the MAX6325ESA?

The MAX6325ESA is rated for continuous operation from –40°C to +85°C. This extended industrial temperature range is confirmed in the Ordering Information table and Electrical Characteristics section, where all guaranteed parameters - including tempco, noise, and load regulation - are specified across this full range. The "E" grade suffix explicitly denotes this –40°C to +85°C rating.

Does the MAX6325ESA require an external capacitor on the NR pin?

No, the NR pin on the MAX6325ESA is optional. As stated in the Pin Description and Applications Information sections, a 1µF capacitor may be added to reduce wideband noise, but the device operates fully specified with NR left open. Larger capacitances provide negligible additional benefit, and omitting the capacitor does not affect DC accuracy, tempco, or long-term stability.

Can the MAX6325ESA drive a 10µF output capacitor without instability?

Yes, the MAX6325ESA is explicitly characterized for stability with output capacitance from 0µF to 100µF across all load currents, per the "Bypassing" section of the datasheet. This design feature eliminates the need for series isolation resistors when driving large capacitive loads such as ADC sample-and-hold circuits or op-amp input stages - a key advantage over many competing references.

What is the purpose of the TRIM pin on the MAX6325ESA?

The TRIM pin on the MAX6325ESA enables ±1% output voltage adjustment using an external 10kΩ potentiometer connected between OUT and GND, with the wiper tied to TRIM. As detailed in Figure 1 and the Detailed Description, this external trimming does not degrade temperature coefficient or noise performance, allowing board-level calibration without altering the internal zener characteristics of the MAX6325ESA.

Is the MAX6325ESA pin-compatible with other members of the MAX6325/MAX6341/MAX6350 family?

Yes, the MAX6325ESA shares identical pin configuration and package (8-pin SO) with MAX6341ESA and MAX6350ESA. All three devices have the same IN, GND, NR, OUT, TRIM pin assignments and internally connected pins (1, 7, 8), enabling direct substitution on the same PCB footprint when only the output voltage differs - provided the application can accommodate 2.5V, 4.096V, or 5V reference levels respectively.