Analog Devices Inc./Maxim Integrated MAX1403CAI+

Overview

MAX1403CAI+ from Maxim Integrated is a low-power, 16-bit, multichannel sigma-delta analog-to-digital converter (ADC) with integrated programmable-gain amplifier (PGA), internal reference input, and serial SPI-compatible interface. It supports up to seven analog inputs (AIN1–AIN5, CALOFF, CALGAIN), operates from a 2.7V–3.6V supply, delivers 16-bit noise-free resolution at 60SPS with SINC3 filtering, and is designed for precision sensor signal conditioning in industrial data acquisition systems.

For engineers reviewing the MAX1403CAI+ datasheet, MAX1403CAI+ pinout, MAX1403CAI+ application, or MAX1403CAI+ equivalent, this page provides verified technical context, confirmed key specifications, validated package and pin mapping, real-world use cases, and two rigorously cross-checked alternative parts - all grounded in the official MAX1403 datasheet and evaluation kit documentation.

Technical Context

The MAX1403CAI+ implements a third-order sigma-delta modulator with selectable SINC1 or SINC3 digital filtering, enabling trade-offs between speed (up to 2.5kSPS) and resolution (16-bit noise-free at 60SPS). Its on-chip PGA offers gain settings of 1× to 128× in binary steps, and three independent transfer function registers (TF1–TF3) allow per-channel unipolar/bipolar range selection and offset correction.

It features dual calibration channels (CALOFF/CALGAIN), burnout current sources (0.1µA), input buffer enable, and flexible clocking via external ceramic resonator (e.g., 2.4576MHz) or crystal. Communication uses a 4-wire SPI-like interface (DIN, DOUT, SCLK, CS) with interrupt-ready signaling via the INT pin.

Key Specifications

Pinout & Package

MAX1403CAI+ is housed in a 28-pin SOIC (Small Outline Integrated Circuit) package with 300-mil body width and standard 1.27mm pitch. The package is RoHS-compliant and rated for surface-mount reflow assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution sigma-delta ADC applications.

Compared with ADS1248IPWR and AD7792BRUZ, the MAX1403CAI+ uniquely combines dedicated CALOFF/CALGAIN pins, external reference flexibility, and proven 16-bit noise-free performance in a 28-pin SOIC - making it optimal for industrial DAQ systems requiring field-serviceable calibration and mixed-sensor interfacing.

Availability

MAX1403CAI+ is available at Aetrix Electronics and suitable for industrial process monitoring, high-accuracy weigh scales, and portable data loggers requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for MAX1403CAI+ 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 high-performance analog, mixed-signal, and power-management ICs for industrial, medical, and communications applications.

The MAX1403CAI+ belongs to Maxim's precision data-acquisition ADC family, designed specifically for low-power, high-resolution sensor interfacing in harsh industrial environments where reliability, calibration flexibility, and small-footprint integration are critical.

FAQ

What is the maximum achievable noise-free resolution of the MAX1403CAI+ and under what conditions?

The MAX1403CAI+ achieves 16-bit noise-free resolution at 60 samples per second (SPS) when configured with the SINC3 digital filter and a stable 2.4576MHz master clock. This specification is measured with buffered inputs, internal reference enabled, and proper PCB layout per the MAX1403EVKIT design - confirming its suitability for precision weighing and industrial control applications demanding ±0.0015% full-scale accuracy. The MAX1403CAI+ maintains this performance across its 0°C to +70°C operating range.

Does the MAX1403CAI+ require an external crystal or can it operate with a ceramic resonator?

Yes, the MAX1403CAI+ is fully compatible with a 2.4576MHz ceramic resonator, as demonstrated on the official MAX1403EVKIT evaluation board using Murata CST2.45MGW040. No external crystal is required - the resonator connects directly to CLKIN/CLKOUT pins with appropriate load capacitors. This reduces BOM cost and improves robustness in vibration-prone industrial environments compared to crystal-based timing solutions.

How does the MAX1403CAI+ handle calibration, and are external components needed?

The MAX1403CAI+ supports hardware-assisted two-point calibration using dedicated CALOFF± and CALGAIN± pins, eliminating the need for external switches or multiplexers. When connected as specified (CALOFF± to GND, CALGAIN± to REFIN±), the device enables automatic offset and gain correction in software. The MAX1403CAI+ does not require external calibration DACs or precision resistors - all calibration logic resides in the host firmware using raw codes read from these pins.

Can the MAX1403CAI+ interface directly with a 3.3V microcontroller SPI port?

Yes, the MAX1403CAI+ supports direct 3.3V SPI interfacing: its DIN, DOUT, SCLK, and CS pins are CMOS-compatible with 3.3V logic levels, and the INT pin is open-drain with internal pull-up. No level-shifting circuitry is required when connecting to standard 3.3V MCUs such as ARM Cortex-M or Renesas RX series. The MAX1403CAI+ also tolerates 2.7V–3.6V DVDD, ensuring robust operation across typical 3.3V supply variations.

What is the purpose of the DS0 and DS1 pins on the MAX1403CAI+, and are they used in standard operation?

DS0 and DS1 are digital input pins on the MAX1403CAI+ that control internal multiplexer routing during calibration sequences - specifically enabling selection between CALOFF and CALGAIN channels when SCAN=1. They are not required for basic ADC operation and remain unused in default configurations. These pins are distinct to the MAX1403 (not present on MAX1401) and are documented in Table 1 of the MAX1403 datasheet under the COMMS register bit definitions.