Analog Devices Inc./Maxim Integrated MAX1325ECM+

Overview

The MAX1325ECM+ from Maxim Integrated is a 4-channel, 14-bit simultaneous-sampling analog-to-digital converter with ±10V input range, ±16.5V fault-tolerant inputs, 250ksps per channel throughput, and 48-pin LQFP package. It features independent track/hold per channel, internal +2.5V reference, and operates over -40°C to +85°C for precision power-grid synchronization and motor control systems.

For engineers reviewing the MAX1325ECM+ datasheet, MAX1325ECM+ pinout, MAX1325ECM+ application, or MAX1325ECM+ equivalent, key selection criteria include bipolar ±10V full-scale range, 50ps channel-to-channel T/H matching, 76.5dB SINAD at 100kHz, 14-bit parallel interface timing, and fault-tolerant analog input protection in industrial measurement systems.

Technical Context

This ADC employs independent track-and-hold amplifiers per channel to preserve phase coherence across all four inputs during simultaneous sampling. Its architecture supports both internal (10MHz) and external clocking up to 12.5MHz, with conversion initiated by CONVST rising edge and results output via 14-bit bidirectional parallel bus.

The device uses a switched-capacitor SAR core with on-chip reference buffering and supports unbuffered external reference input (2.0V–3.0V). Digital interface logic is powered separately (DVDD = 2.7V–5.25V), while analog section runs from AVDD = 4.75V–5.25V, enabling mixed-supply system integration.

Key Specifications

Pinout & Package

Package: 48-pin LQFP (7mm × 7mm footprint), RoHS-compliant, moisture-sensitive level 3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 14-bit simultaneous-sampling ADC applications.

Compared with AD7656ASTZ and ADS8588SIPM, the MAX1325ECM+ offers native 14-bit parallel interface timing, integrated +2.5V reference, and identical 48-LQFP footprint-reducing PCB redesign effort while maintaining phase-coherent 4-channel acquisition for legacy industrial controller upgrades.

Availability

MAX1325ECM+ is available at Aetrix Electronics and suitable for power-grid synchronization, multiphase motor control, and power-factor monitoring applications requiring stable component supply, long-term industrial lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX1325ECM+ 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 precision analog and mixed-signal ICs for industrial, automotive, and communications markets, emphasizing high reliability and performance under extreme conditions.

The MAX1316–MAX1326 family was developed specifically for high-fidelity, phase-coherent multichannel data acquisition in power quality analyzers, motor drives, and grid-edge intelligence systems where input protection and timing fidelity are critical.

FAQ

What is the maximum sample rate per channel for the MAX1325ECM+?

The MAX1325ECM+ achieves 250ksps per channel when all four channels are active. This throughput is maintained with either internal (10MHz) or external clocking up to 12.5MHz. The device completes conversion of all four channels in 3.7µs, enabling precise capture of fast transients in power electronics and motor control applications. The MAX1325ECM+ specification sheet confirms this value under "External-Clock Throughput Rate" with eight-channel operation at 250ksps/ch as baseline scaling.

Does the MAX1325ECM+ require external calibration for production use?

No, the MAX1325ECM+ does not require external calibration. It guarantees ±1.5 LSB integral nonlinearity (INL) and ±1 LSB differential nonlinearity (DNL) across temperature, with no missing codes. These specifications are factory-trimmed and verified per production test flow. The MAX1325ECM+ datasheet explicitly states "No Calibration Needed" in its features list and provides typical INL/DNL plots confirming monotonic behavior across full code range.

What is the purpose of the MSV pin on the MAX1325ECM+?

On the MAX1325ECM+, the MSV (Midscale Voltage) pin must be connected directly to AGND. This is required because the MAX1325ECM+ is a bipolar-input device (±10V range), unlike unipolar variants that require a 2.2µF + 0.1µF capacitor network from MSV to AGND. Connecting MSV to AGND establishes the correct common-mode reference for the internal analog front-end and ensures proper operation of the track/hold circuitry per the MAX1325ECM+ pin description table.

Can the MAX1325ECM+ operate with only an analog supply voltage?

No, the MAX1325ECM+ requires two independent supplies: AVDD (4.75V–5.25V) for the analog section and DVDD (2.7V–5.25V) for the digital interface. Both AVDD and DVDD must be present and properly bypassed. The MAX1325ECM+ datasheet specifies absolute maximum ratings and operating conditions for both rails, and functional operation is not guaranteed if DVDD is omitted-even if digital pins are left floating-because internal logic and output drivers depend on DVDD.

How does the fault-tolerance specification apply to the MAX1325ECM+ analog inputs?

The MAX1325ECM+ analog inputs (CH0–CH3) are rated for ±16.5V fault tolerance relative to AGND. This means each input can withstand transient overvoltages up to ±16.5V without damage or parametric shift, even when the device is unpowered. This protection is implemented via internal clamping structures and applies regardless of whether the input is actively sampled or in track mode. The MAX1325ECM+ datasheet lists this value explicitly in the Absolute Maximum Ratings table for "CH0–CH7, I.C. to AGND (MAX1324/MAX1325/MAX1326)".