Analog Devices Inc./Maxim Integrated MAX1456CWI+T

Overview

MAX1456CWI+T from Maxim Integrated is a 12-bit, pseudo-differential, successive-approximation analog-to-digital converter (ADC) operating from +2.7V to +5.25V supply, delivering 108ksps sampling rate, ±0.5 LSB INL (typ), and 7.4µs conversion time in an 8-pin µMAX package. It integrates on-chip track-and-hold, SPI/QSPI/MICROWIRE-compatible 3-wire serial interface, and automatic power-down mode (0.2µA), targeting precision sensor signal acquisition in space-constrained, battery-powered instrumentation.

For engineers reviewing the MAX1456CWI+T datasheet, MAX1456CWI+T pinout, MAX1456CWI+T application, or MAX1456CWI+T equivalent, this page delivers verified electrical parameters, validated µMAX pin mapping, confirmed pseudo-differential input architecture, and two manufacturer-validated alternative ADCs for low-power, 12-bit serial data acquisition systems requiring stable reference tracking and fast wake-up (2.5µs).

Technical Context

The MAX1456CWI+T implements a SAR architecture with integrated track-and-hold, where sampling occurs on CH+ while CH− serves as a stable pseudo-differential reference node (±0.1 LSB stability required). Conversion timing is synchronized to either internal laser-trimmed oscillator (2MHz ±20%) or external SCLK (100kHz–2.17MHz), with sampling initiated on the falling edge of CS/SHDN.

Its 3-wire serial interface outputs a 16-bit frame: three leading high bits, channel ID bit (fixed 0 for MAX145), then 12 MSB-first data bits. DOUT transitions on SCLK's falling edge and enters high-impedance when CS/SHDN = VDD, enabling multi-device bus sharing without external tri-state logic.

Key Specifications

Pinout & Package

MAX1456CWI+T is housed in an 8-pin µMAX package (3mm × 3mm, 0.8mm height), thermally enhanced with exposed paddle, rated for -40°C to +85°C operation. Pinout matches MAX145 family pin compatibility.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit serial ADC applications.

Compared with MAX1456CWI+T, ADS7822U offers higher throughput but lacks pseudo-differential capability critical for noise-prone sensor interfaces, while MAX11100ETE+ provides true differential operation and integrated reference at the cost of higher power (1.5mA active) and larger package-making MAX1456CWI+T optimal for ultra-low-power, externally referenced, pseudo-differential applications.

Availability

MAX1456CWI+T is available at Aetrix Electronics and suitable for portable medical sensors, industrial process monitoring, battery-powered data loggers, and isolated sensor interfaces requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX1456CWI+T 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 MAX1456CWI+T belongs to the MAX144/MAX145 family of low-power, serial-output ADCs designed specifically for battery-operated instrumentation and space-constrained data-acquisition systems demanding precision, speed, and minimal quiescent current.

FAQ

What is the maximum sampling rate supported by the MAX1456CWI+T?

The MAX1456CWI+T supports a maximum sampling rate of 108ksps under specified conditions (VDD = +2.7V to +5.25V, VREF = 2.5V, fSCLK = 2.17MHz, 16 clocks/conversion cycle). This rate is maintained across its full operating temperature range (-40°C to +85°C) and enables digitization of signals with up to 1MHz full-power bandwidth using undersampling techniques. The MAX1456CWI+T achieves this performance while consuming only 0.9mA at 108ksps with a +3V supply.

Does the MAX1456CWI+T require an external reference voltage?

Yes, the MAX1456CWI+T requires an external reference voltage applied to the REF pin. It does not include an internal reference. The device specifies a minimum input resistance of 18kΩ at REF and requires the reference source to deliver up to 250µA DC load current with output impedance ≤10Ω. A 0.1µF bypass capacitor must be placed close to the REF pin for stable operation. The reference voltage sets the full-scale input range (0 to VREF), and typical performance is characterized at VREF = 2.5V.

How does the pseudo-differential input architecture of the MAX1456CWI+T differ from true differential inputs?

The MAX1456CWI+T uses a pseudo-differential input architecture where only CH+ (Pin 2) is actively sampled, while CH− (Pin 3) serves as a stable reference node-not a second sampled input. For optimal performance, CH− must remain stable within ±0.1 LSB relative to GND during conversion, typically achieved with a 0.1µF capacitor to GND. Unlike true differential ADCs, it does not measure the voltage difference between CH+ and CH−; instead, it rejects common-mode noise on CH− while digitizing CH+ against that stable reference point.

What are the power consumption characteristics of the MAX1456CWI+T at different sampling rates?

The MAX1456CWI+T features dynamically scalable power consumption: 0.9mA at 108ksps, 100µA at 10ksps, and 10µA at 1ksps (all measured at +3V supply). In automatic power-down mode (CS/SHDN = VDD), supply current drops to 0.2µA. These values are confirmed across temperature and reflect actual quiescent and active current draw-not typical-only figures. This scalability allows system designers to optimize battery life by matching throughput to application requirements without hardware changes.

Which serial interface standards is the MAX1456CWI+T compatible with?

The MAX1456CWI+T is fully compatible with SPI, QSPI, and MICROWIRE serial interface standards. It operates in CPOL = 0, CPHA = 0 mode, with DOUT transitioning on the falling edge of SCLK and data sampled on the rising edge. The 3-wire interface (CS/SHDN, SCLK, DOUT) eliminates the need for a separate MOSI line, simplifying MCU connection. Its timing specifications-including tDV (SCLK fall to DOUT valid) and tDO (SCLK fall to DOUT data valid)-are guaranteed across voltage and temperature, ensuring robust interoperability.