Analog Devices Inc./Maxim Integrated MAX1274ACTC

Overview

MAX1274ACTC from Maxim Integrated is a 12-bit, true-differential, serial-output analog-to-digital converter (ADC) with 1.8Msps throughput, ±1 LSB INL DC accuracy, and operation from a single +4.75V to +5.25V supply. It features unipolar input range (0 to VREF), external reference support, and a 3-wire SPI/QSPI/MICROWIRE interface-designed for high-noise industrial motor control and base-station data acquisition systems.

For engineers reviewing the MAX1274ACTC datasheet, MAX1274ACTC pinout, MAX1274ACTC application, or MAX1274ACTC equivalent, this page delivers verified technical context, real-world timing behavior, power-down mode trade-offs, and validated alternative options for unipolar 12-bit SAR ADC selection in space- and power-constrained embedded signal chains.

Technical Context

The MAX1274ACTC implements a successive-approximation register (SAR) architecture with an internal true-differential track-and-hold (T/H), enabling noise-immune sampling of differential analog signals up to 20MHz small-signal bandwidth. Its conversion is initiated by CNVST falling edge and clocked by SCLK, requiring exactly 16 SCLK cycles per 12-bit result plus 3 leading zeros.

It supports three operational modes: normal (9–11mA VDD current), partial power-down (1mA), and full power-down (1µA max), all controlled via timed CNVST/SCLK sequencing. The separate VL supply (1.8V to VDD) enables direct interfacing with low-voltage digital logic without level shifters.

Key Specifications

Pinout & Package

MAX1274ACTC is housed in a 12-pin 3mm × 3mm TQFN package with exposed paddle (EP), rated for -40°C to +85°C operation. Pin 1 is AIN-, pin 12 is AIN+, and EP is internally connected to GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS8325IDRCT and AD7476ARTZ-REEL7, the MAX1274ACTC uniquely combines true-differential input, 1.8Msps throughput, and independent VL supply-making it the only option among the three capable of high-fidelity, high-speed, low-power unipolar sampling in electrically noisy industrial environments.

Availability

MAX1274ACTC is available at Aetrix Electronics and suitable for industrial motor control, base-station IF digitization, and portable test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX1274ACTC 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, communications, and computing markets.

The MAX1274ACTC belongs to Maxim's precision high-speed ADC product line, engineered for applications demanding true-differential input integrity, low-power operation, and seamless integration with DSP/microcontroller serial interfaces.

FAQ

What is the maximum sampling rate supported by the MAX1274ACTC?

The MAX1274ACTC supports a maximum throughput rate of 1.8Msps, achieved with a 28.8MHz SCLK and minimum conversion time of 0.556µs. This rate is sustained in continuous conversion mode when CNVST is pulsed appropriately between SCLK cycles. At lower rates (e.g., 10ksps), the full-linear bandwidth reduces to 5kHz, as specified in the datasheet.

Does the MAX1274ACTC require an external reference voltage?

Yes, the MAX1274ACTC requires an external reference voltage applied to the REF pin. The device accepts VREF from +1.0V to VDD + 50mV, with optimal performance at 4.096V. A 0.01µF ceramic capacitor and 4.7µF tantalum capacitor must be placed from REF to RGND to ensure stability and 12-bit accuracy across temperature.

How does the MAX1274ACTC differ from the MAX1275ACTC?

The MAX1274ACTC features a unipolar input range (0V to VREF), while the MAX1275ACTC provides a bipolar range (−VREF/2 to +VREF/2). Both share identical package, pinout, timing, power modes, and AC performance-but their transfer functions differ: MAX1274ACTC outputs straight binary code, whereas MAX1275ACTC outputs two's complement format.

Can the MAX1274ACTC interface directly with a 1.8V microcontroller?

Yes, the MAX1274ACTC supports direct interfacing with 1.8V logic via its dedicated VL supply pin (Pin 7), which accepts 1.8V to VDD. Digital I/O thresholds scale with VL, and DOUT drives valid logic levels compatible with 1.8V systems-eliminating the need for external level shifters in mixed-voltage designs.

What are the power-down modes available on the MAX1274ACTC?

The MAX1274ACTC offers two power-down modes: partial power-down (1mA VDD current) and full power-down (1µA max VDD current). Entry into either mode is controlled by precise timing of CNVST relative to SCLK edges-no configuration registers or I²C commands are needed. Recovery times are 16 SCLK cycles (partial) and 2ms (full), as verified in the datasheet timing tables.