Analog Devices Inc./Maxim Integrated MAX157AEUA+T

Overview

MAX157AEUA+T from Maxim Integrated is a low-power, 10-bit successive-approximation analog-to-digital converter (SAR ADC) with two single-ended input channels, 108ksps sampling rate, ±0.5 LSB differential nonlinearity, and SPI/QSPI/MICROWIRE-compatible 3-wire serial interface - designed for precision signal acquisition in space-constrained, battery-powered instrumentation and portable data loggers.

For engineers reviewing the MAX157AEUA+T datasheet, MAX157AEUA+T pinout, MAX157AEUA+T application, or MAX157AEUA+T equivalent, this page delivers verified electrical specifications, µMAX-8 package terminal mapping, real-world use scenarios, and validated alternative parts - all grounded in Maxim's official 19-1388 Rev 0 datasheet and ordering information.

Technical Context

The MAX157AEUA+T implements a SAR architecture with integrated track/hold, laser-trimmed internal clock (±20% of 2MHz), and automatic power-down mode (<0.2µA shutdown current). It supports both internal and external clock modes, with conversion initiated on CS/SHDN falling edge and data output synchronized to SCLK falling edge.

Analog input structure includes 9kΩ input resistance and 16pF input capacitance per channel; acquisition time is 2.5µs (typical), and full-power bandwidth is 1.0MHz. The device requires an external reference (0–VDD+50mV range) and accepts single-ended inputs from 0 to VREF on CH0 and CH1, with channel alternation controlled via CS/SHDN toggling.

Key Specifications

Pinout & Package

MAX157AEUA+T is housed in an 8-pin µMAX package (3.0mm × 3.0mm, 0.8mm height, exposed pad), rated for -40°C to +85°C operation and compatible with fine-pitch PCB assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit SAR ADC applications.

Compared with MAX157AEUA+T, MAX144BCPA+ trades speed for resolution and relaxed DNL, while ADS7822U increases throughput but shifts T/H design responsibility to the user - making MAX157AEUA+T optimal for balanced, self-contained, low-power dual-channel acquisition.

Availability

MAX157AEUA+T is available at Aetrix Electronics and suitable for battery-powered data loggers, portable medical sensors, industrial process monitoring nodes, and test equipment requiring stable component supply with guaranteed long-term sourcing.

Supply support for MAX157AEUA+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 U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The MAX157 family was engineered for ultra-low-power, space-constrained data acquisition - targeting portable instrumentation, sensor interfaces, and energy-harvesting systems where integration, supply flexibility, and guaranteed monotonicity are critical.

FAQ

What is the maximum sampling rate of the MAX157AEUA+T?

The MAX157AEUA+T achieves a maximum sampling rate of 108ksps under specified conditions: VDD = +2.7V to +5.25V, fSCLK = 2.17MHz (external clock mode), and 16 clock cycles per conversion. This rate is maintained across its full operating temperature range (-40°C to +85°C) and supports real-time digitization of signals up to ~50kHz with adequate anti-alias filtering. The MAX157AEUA+T maintains this performance without external timing components due to its integrated track/hold and configurable clock modes.

Does the MAX157AEUA+T require an external reference voltage?

Yes, the MAX157AEUA+T requires an external reference voltage applied to the REF pin. It accepts 0V to (VDD + 50mV), with optimal performance at 2.5V. The reference must deliver ≥250µA DC load current during conversion and exhibit ≤10Ω output impedance; a 0.1µF ceramic capacitor is mandatory at the REF pin for noise suppression. The MAX157AEUA+T does not include an internal reference, so accuracy and stability depend entirely on the external source - making it compatible with precision references like the MAX6126 or REF5025.

How does channel selection work on the MAX157AEUA+T?

The MAX157AEUA+T features two single-ended analog inputs (CH0 and CH1) and alternates between them automatically: CH0 is sampled first after power-on or CS/SHDN assertion, followed by CH1, then CH0 again. Channel switching is controlled solely by the CS/SHDN pin - toggling it low initiates the next conversion on the alternate channel. To sample the same channel repeatedly, assert and deassert CS/SHDN twice within one conversion cycle. The channel ID bit (CHID) appears in the serial output stream, allowing firmware to distinguish source channel without external multiplexing logic.

What package type is used for the MAX157AEUA+T?

The MAX157AEUA+T is packaged in an 8-pin µMAX package (3.0mm × 3.0mm body, 0.8mm height, exposed thermal pad), rated for operation from -40°C to +85°C. This leaded surface-mount package offers superior thermal performance and smaller footprint than SOIC-8 or PDIP-8 variants, supporting high-density PCB layouts in portable and embedded systems. The "AEUA" suffix in the part number explicitly denotes the µMAX-8 package with industrial temperature grade, per Maxim's official ordering information table.

Can the MAX157AEUA+T operate with a 3.3V supply?

Yes, the MAX157AEUA+T operates fully across +2.7V to +5.25V, including standard 3.3V logic rails. At VDD = +3.3V, typical supply current is 0.9mA at 108ksps and <0.2µA in shutdown - delivering optimal power efficiency for 3.3V microcontroller-based systems. Electrical characteristics including INL (±0.5 LSB), DNL (±0.5 LSB), and SINAD (66dB) are guaranteed across this voltage range, and the SPI-compatible serial interface aligns directly with 3.3V GPIO levels without level translation.