Analog Devices Inc./Maxim Integrated MAX71071+

Overview

MAX71071+ from Maxim Integrated is a dual-channel isolated metrology ADC designed for high-accuracy current and voltage measurement in energy metering systems. It features 24-bit resolution, 0.1% accuracy over 2000:1 current range, compatibility with 50µΩ shunt resistors, and operates from power delivered via pulse transformer from a MAX71xxx host controller - enabling CT-free, compact meter designs.

For engineers reviewing the MAX71071+ datasheet, MAX71071+ pinout, MAX71071+ application, or MAX71071+ equivalent, key selection considerations include isolated power delivery architecture, IEC 62053/ANSI C12.20 compliance, on-chip temperature sensor for host-based digital compensation, and µMAX-10 package integration in space-constrained meter PCBs.

Technical Context

The MAX71071+ implements two independent 24-bit sigma-delta ADC channels with galvanic isolation achieved via integrated pulse transformer coupling - not optocouplers or capacitive isolators. Its isolated data, clock, and power path eliminates external isolation components while maintaining ±0.1% gain error and <±5ppm/°C gain drift across –40°C to +85°C.

It requires a compatible MAX71xxx host (e.g., MAX71070) to supply regulated power through the transformer and execute command-driven configuration. On-chip power monitoring and temperature sensing are digitized and transmitted to the host for real-time calibration correction.

Key Specifications

Pinout & Package

MAX71071+ is housed in a 10-pin µMAX® package (3mm × 3mm, 0.5mm pitch), thermally enhanced with exposed pad. Pin functions are defined relative to isolated primary (host-facing) and secondary (measurement-facing) sides.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar isolated metrology ADC applications.

Compared with ADE9153A and AMC1306M25, the MAX71071+ uniquely combines dual-channel 24-bit conversion, transformer-powered isolation, and host-coordinated digital compensation - offering optimal balance of integration, accuracy, and system-level design control for certified meter platforms.

Availability

MAX71071+ is available at Aetrix Electronics and suitable for industrial energy meters, residential smart meters, and smart grid monitoring systems requiring stable component supply, long-lifecycle support, and certified metrology performance.

Supply support for MAX71071+ 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) is a semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX71071+ belongs to the MAX71xx metrology ADC family, engineered specifically for revenue-grade, CT-free energy measurement in utility-grade meters - emphasizing accuracy, isolation integrity, and host-managed calibration.

FAQ

What is the isolation rating of the MAX71071+?

The MAX71071+ achieves galvanic isolation via an integrated pulse transformer, rated to withstand ≥5kV RMS per IEC 61000-4-5 surge testing. It does not specify a continuous working voltage like optocouplers or capacitive isolators; instead, its isolation integrity is validated within the full MAX71xxx host system architecture. The MAX71071+ relies on transformer-coupled power and data transfer - eliminating need for external isolation components while meeting safety standards for metering applications.

Does the MAX71071+ require an external voltage reference?

No, the MAX71071+ integrates a precision internal voltage reference optimized for metrology accuracy. This reference is factory-trimmed and temperature-compensated, supporting the ±0.1% gain accuracy over temperature and linearity. External references are neither required nor supported - all calibration and compensation are performed by the host using the on-chip temperature sensor and known shunt characteristics. The MAX71071+ delivers fully scaled 24-bit digital results directly to the host.

Can the MAX71071+ operate without a MAX71xxx host controller?

No, the MAX71071+ cannot operate autonomously. It depends entirely on a compatible MAX71xxx host (e.g., MAX71070) for power delivery via pulse transformer, clock generation, command sequencing, and data readout. The MAX71071+ contains no internal oscillator, regulator, or nonvolatile memory - it functions strictly as a slave metrology front-end. Without the host, the MAX71071+ remains unpowered and nonfunctional.

What is the role of the PWRMON pin on the MAX71071+?

On the MAX71071+, the PWRMON pin outputs a logic-level signal indicating valid operation of the pulse-transformer power delivery. When asserted, it confirms that sufficient energy is being coupled from the host to sustain ADC conversion and internal circuitry. Host firmware uses PWRMON to detect transformer coupling faults, open-circuit conditions, or insufficient drive - enabling early failure detection before measurement corruption occurs. This diagnostic capability is unique to the MAX71071+ among isolated metrology ADCs.

How does the on-chip temperature sensor in the MAX71071+ improve meter accuracy?

The MAX71071+ integrates a calibrated on-die temperature sensor whose analog output is digitized and transmitted to the host. The host uses this value - combined with known thermal coefficients of the shunt resistor and internal gain stages - to apply real-time digital compensation to voltage and current measurements. This eliminates need for external temperature sensors and associated layout complexity, directly improving long-term accuracy stability across –40°C to +85°C. The MAX71071+'s temperature sensor enables localized, per-device correction unmatched by board-level sensing.