Analog Devices Inc./Maxim Integrated MAX1241BEPA

Overview

MAX1241BEPA 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 features internal track/hold with 1.5µs acquisition time - ideal for portable data logging and isolated sensor interfaces where space and power are constrained.

For engineers reviewing the MAX1241BEPA datasheet, MAX1241BEPA pinout, MAX1241BEPA application, or MAX1241BEPA equivalent, this page delivers verified electrical specs, validated pin functions, confirmed operating modes (normal/shutdown), real-world timing constraints (tACQ = 1.5µs, tCONV = 7.5µs), and precise interface compatibility with microcontroller I/O ports - all critical for battery-powered system design and layout-sensitive signal acquisition.

Technical Context

The MAX1241BEPA implements a capacitive SAR architecture with integrated track/hold, eliminating need for external hold capacitors. Its analog front-end accepts inputs from 0V to VREF with ±0.5 LSB INL and 70dB SINAD at 10kHz, while the digital interface uses unipolar MSB-first serial output synchronized to SCLK falling edges.

Conversion is initiated by CS falling edge; DOUT transitions high to signal end-of-conversion (EOC), enabling flexible read timing. Shutdown mode reduces supply current to ≤2µA, and wake-up delay depends on external REF bypass capacitance - 4µs for MAX1241 with stable external reference, unlike MAX1240's capacitor-dependent recovery.

Key Specifications

Pinout & Package

MAX1241BEPA is housed in an 8-pin plastic DIP (PDIP) package with through-hole mounting and 0.3-inch body width. Pin spacing is 0.1 inch, compatible with standard prototyping and industrial PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MAX11131AUT+, the MAX1241BEPA uniquely balances 73ksps throughput, ultra-low shutdown current (≤2µA), and true 3-wire simplicity - making it optimal for space-constrained, battery-operated systems requiring minimal external components and guaranteed acquisition timing.

Availability

MAX1241BEPA is available at Aetrix Electronics and suitable for battery-powered systems, portable data logging, isolated data acquisition, and process control applications requiring stable component supply, long-lifecycle support, and RoHS-compliant through-hole packaging.

Supply support for MAX1241BEPA 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 demanding industrial, medical, and communications applications - emphasizing low power, small size, and high reliability.

The MAX1240/MAX1241 product line delivers ultra-low-power, 12-bit serial ADCs optimized for remote sensing and portable instrumentation, featuring integrated track/hold, wide supply range, and minimal external component requirements.

FAQ

What is the maximum sampling rate supported by the MAX1241BEPA?

The MAX1241BEPA supports a maximum throughput rate of 73ksps, achieved with a 2.1MHz SCLK and proper timing adherence (tCS ≥ 240ns). This rate corresponds to a 7.5µs conversion time and is specified under conditions of VDD = +2.7V to +5.25V, fSCLK = 2.1MHz, and external VREF = 2.500V. The MAX1241BEPA maintains full 12-bit performance at this rate, with SINAD = 70dB and INL = ±0.5 LSB.

Does the MAX1241BEPA include an internal voltage reference?

No, the MAX1241BEPA does not include an internal voltage reference. Unlike the MAX1240 series, the MAX1241BEPA requires an external reference applied to the REF pin, supporting input voltages from 1.0V to VDD. The REF pin must be bypassed with at least 0.1µF capacitance, and the external reference must supply up to 250µA DC load current with ≤10Ω output impedance to maintain specified accuracy.

What are the key timing requirements for reliable communication with the MAX1241BEPA?

Reliable serial communication with the MAX1241BEPA requires: CS falling edge to initiate conversion; minimum CS pulse width of 240ns; SCLK frequency ≤2.1MHz with ≥200ns high/low time; and DOUT data valid within 20ns to 200ns after SCLK falling edge. The end-of-conversion (EOC) is signaled by DOUT rising edge, and at least 13 SCLK falling edges are needed to read the 12-bit result plus leading EOC bit.

How does shutdown mode operate on the MAX1241BEPA?

Shutdown mode on the MAX1241BEPA is activated by pulling the SHDN pin low, reducing supply current to ≤2µA. The device wakes up in 4µs - a fixed delay independent of external capacitance because the MAX1241BEPA relies on an external reference that remains active. During shutdown, the internal track/hold, SAR, and serial interface are disabled, but the REF pin remains functional for external reference continuity.

Which microcontroller interfaces are compatible with the MAX1241BEPA serial protocol?

The MAX1241BEPA serial interface is fully compatible with SPI, QSPI, and MICROWIRE standards when configured with CPOL = 0 and CPHA = 0. It connects directly to standard GPIO or hardware SPI peripherals on ARM Cortex-M, PIC, AVR, and MSP430 microcontrollers. No level-shifting is required for 3.3V or 5V logic families, and the 3-wire (SCLK, CS, DOUT) topology minimizes I/O pin usage compared to 4-wire alternatives.