Analog Devices Inc./Maxim Integrated MAX1241CEPA+

Overview

MAX1241CEPA+ 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 +2.7V to +5.25V, requires an external reference (0V to VREF input range), and targets space-constrained, battery-powered data acquisition systems.

For engineers reviewing the MAX1241CEPA+ datasheet, MAX1241CEPA+ pinout, MAX1241CEPA+ application, or MAX1241CEPA+ equivalent, this page delivers verified specifications, validated pin functions, confirmed operating conditions (0°C to +70°C, ±1 LSB INL), and real-world alternative options for precision 12-bit ADC selection in remote sensor and portable instrumentation designs.

Technical Context

The MAX1241CEPA+ implements a track/hold circuit with 1.5µs acquisition time and a 12-bit SAR architecture using an internal capacitive DAC. Conversion is initiated by CS falling edge, with end-of-conversion signaled by DOUT high transition.

It supports unipolar binary output (MSB-first), accepts external references from +1.0V to VDD, and features a three-level SHDN pin enabling shutdown mode (≤2µA) or external reference selection. The 3-wire interface operates up to 2.1MHz with unrestricted duty cycle (≥200ns per phase).

Key Specifications

Pinout & Package

MAX1241CEPA+ is housed in an 8-pin plastic DIP (PDIP) package with through-hole mounting and 0.3-inch body width. Pin spacing conforms to JEDEC MS-001 standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX1241CEPA+, ADS7822U offers higher speed but removes autonomous shutdown control, while AD7490BRUZ trades pin count and reference flexibility for channel density and integrated reference-making MAX1241CEPA+ optimal for minimal-footprint, externally referenced, ultra-low-power single-channel acquisition.

Availability

MAX1241CEPA+ is available at Aetrix Electronics and suitable for battery-powered data loggers, isolated sensor interfaces, and portable instrumentation requiring stable component supply with guaranteed long-term manufacturability.

Supply support for MAX1241CEPA+ 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, mixed-signal, and power management ICs for demanding industrial, medical, and communications applications.

The MAX1240/MAX1241 family delivers low-power, 12-bit serial ADCs optimized for remote sensing and portable instrumentation where size, power, and ease of microcontroller interfacing are critical.

FAQ

What is the maximum sampling rate of the MAX1241CEPA+?

The MAX1241CEPA+ achieves a maximum throughput rate of 73ksps, corresponding to a 7.5µs conversion time. This rate is specified under conditions of VDD = +2.7V to +5.25V, fSCLK = 2.1MHz, and TA = 0°C to +70°C. At lower sampling rates, power consumption scales down-for example, to 66µW at 1ksps-enabling adaptive power management in MAX1241CEPA+ implementations.

Does the MAX1241CEPA+ include an internal voltage reference?

No, the MAX1241CEPA+ requires an external reference voltage applied to the REF pin. Unlike the MAX1240 variant, it does not integrate an internal 2.5V reference. The MAX1241CEPA+ accepts external references from +1.0V to VDD, with specified performance requiring ≤10Ω source impedance and ability to supply 250µA during conversion. This design gives system designers full control over reference accuracy, temperature drift, and noise performance in the MAX1241CEPA+ signal chain.

What are the valid logic levels for the SHDN pin on the MAX1241CEPA+?

On the MAX1241CEPA+, SHDN is a three-level control: logic low (≤0.4V) places the device in shutdown mode (≤2µA supply current); an open (unconnected) state enables normal operation with external reference; and logic high (≥VDD − 0.4V) also enables operation but has no special function for MAX1241CEPA+ (unlike MAX1240, where high enables internal reference). The MAX1241CEPA+ is fully functional with SHDN either open or tied high-no pull-up resistor is required.

Can the MAX1241CEPA+ interface directly with a 5V microcontroller SPI port?

Yes, the MAX1241CEPA+ supports VDD up to +5.25V and its digital I/O pins (CS, SCLK, DOUT) are 5V-tolerant with VIH ≥0.7×VDD and VIL ≤0.3×VDD. When powered from 5V, the MAX1241CEPA+ accepts standard 5V logic levels directly-no level-shifting circuitry is needed. Its 3-wire interface is compatible with SPI, QSPI, and MICROWIRE protocols, and DOUT transitions on SCLK falling edge while data is sampled on rising edge, matching standard SPI Mode 0 (CPOL = 0, CPHA = 0) timing for seamless MAX1241CEPA+ integration.

What is the input voltage range specification for the AIN pin on the MAX1241CEPA+?

The AIN pin on the MAX1241CEPA+ accepts analog input voltages from 0V to VREF, where VREF is the voltage applied to the REF pin. Absolute maximum ratings allow AIN to swing from GND − 0.3V to VDD + 0.3V without damage, but accurate conversion requires staying within the 0V to VREF range. For example, with a 3.3V external reference, the valid input range is 0–3.3V; exceeding VREF by more than 50mV degrades linearity, and input current must be limited to 2mA if the signal exceeds supply rails. This behavior is explicitly defined for MAX1241CEPA+ in the Electrical Characteristics table.