Analog Devices Inc./Maxim Integrated MAX1241ACSA+T

Overview

MAX1241ACSA+T from Maxim Integrated is a low-power, 12-bit successive-approximation analog-to-digital converter (ADC) with 73ksps throughput, 7.5µs conversion time, and SPI/QSPI/MICROWIRE-compatible 3-wire serial interface. It operates from a single +2.7V to +5.25V supply, requires an external reference (0V to VREF input range), and targets space-constrained, battery-powered data acquisition systems.

For engineers reviewing the MAX1241ACSA+T datasheet, MAX1241ACSA+T pinout, MAX1241ACSA+T application, or MAX1241ACSA+T equivalent, this page delivers verified electrical specs, validated SO-8 package mapping, confirmed shutdown behavior (2µA), real-world timing constraints (tACQ = 1.5µs, tCONV = 7.5µs), and two rigorously cross-checked alternative ADCs for low-voltage, serial-interface designs.

Technical Context

The MAX1241ACSA+T implements a track/hold stage followed by a 12-bit SAR core, acquiring signals in 1.5µs and completing conversion in 7.5µs. Its internal clock eliminates external timing components, while the 3-wire serial interface supports unipolar MSB-first output with EOC signaling via DOUT high transition.

It accepts external reference voltages from 1.0V to VDD (≤5.25V), supports 2.1MHz SCLK with ≥200ns pulse width, and features programmable shutdown via SHDN pin - pulling low reduces supply current to ≤2µA, with wake-up delay dependent on external REF bypass capacitance.

Key Specifications

Pinout & Package

MAX1241ACSA+T is housed in an 8-pin SO (Small Outline) package, RoHS-compliant and lead-free (+ suffix), with standard JEDEC MS-012AC footprint (5.0mm × 6.2mm, 1.27mm pitch).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and AD7476ARMZ, the MAX1241ACSA+T offers optimal balance of ultra-low shutdown current (2µA), guaranteed 1.5µs acquisition, and true 3-wire simplicity - making it superior for energy-constrained, space-limited, and isolation-sensitive designs where 73ksps suffices.

Availability

MAX1241ACSA+T is available at Aetrix Electronics and suitable for battery-powered systems, portable data logging, isolated data acquisition, and process control requiring stable component supply and long-term manufacturability.

Supply support for MAX1241ACSA+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, automotive, and communications markets.

The MAX1240/MAX1241 product line was designed specifically for low-power, space-constrained data acquisition systems requiring high-resolution digitization with minimal external components and robust serial interfacing.

FAQ

What is the reference voltage configuration for MAX1241ACSA+T?

The MAX1241ACSA+T requires an external reference voltage applied to the REF pin, with valid range from 1.0V to VDD (up to +5.25V). Unlike the MAX1240, it has no internal reference. The device achieves specified accuracy only when the external reference meets load current (≤250µA) and output impedance (≤10Ω) requirements, and is bypassed with ≥0.1µF ceramic capacitor.

Does MAX1241ACSA+T support SPI, QSPI, and MICROWIRE protocols simultaneously?

Yes - the MAX1241ACSA+T serial interface is electrically compatible with SPI (CPOL=0, CPHA=0), QSPI (13-clock readout), and MICROWIRE standards. It uses unidirectional DOUT, shared SCLK and CS, and requires no mode pins or configuration registers to switch between protocols - hardware-level interoperability is built-in.

What is the minimum acquisition time required before asserting CS on MAX1241ACSA+T?

The MAX1241ACSA+T specifies a maximum track/hold acquisition time (tACQ) of 1.5µs - this is both the longest time needed to acquire the signal and the shortest safe interval after AIN stabilization before pulling CS low. For source impedances <1kΩ, 1.5µs is sufficient; higher impedances require longer acquisition per tACQ = 9(RS + 9kΩ) × 16pF.

How does shutdown mode affect wake-up timing in MAX1241ACSA+T?

In MAX1241ACSA+T, pulling SHDN low reduces supply current to ≤2µA. Wake-up delay is fixed at ~4µs because the device uses an external reference - unlike the MAX1240, no internal reference capacitor recharge is needed. Conversion may be initiated immediately after SHDN returns high, provided CS timing constraints (tCS ≥ 240ns) are met.

Can MAX1241ACSA+T interface directly with a 5V microcontroller?

Yes - the MAX1241ACSA+T supports VDD up to +5.25V and all digital inputs (CS, SCLK, SHDN) tolerate 0V to +6V. Its DOUT output swings rail-to-rail (0V to VDD), so it drives 5V logic levels natively. No level shifters are required when interfacing with 5V MCUs, provided GND is common and VDD is set to 5V.