Analog Devices Inc./Maxim Integrated MAX144BEPA+

Overview

MAX144BEPA+ from Maxim Integrated is a low-power, 12-bit successive-approximation analog-to-digital converter (SAR ADC) with two single-ended input channels, 108ksps sampling rate, ±1 LSB INL, and operation from +2.7V to +5.25V supply. It features an on-chip track-and-hold, SPI/QSPI/MICROWIRE-compatible 3-wire serial interface, and automatic power-down mode consuming only 0.2µA in shutdown - ideal for battery-powered instrumentation and portable data loggers.

For engineers reviewing the MAX144BEPA+ datasheet, MAX144BEPA+ pinout, MAX144BEPA+ application, or MAX144BEPA+ equivalent, this page delivers verified electrical parameters, temperature-rated package details (-40°C to +85°C), functional pin roles, real-world use cases in isolated data acquisition and system supervision, and two validated alternative parts with documented technical and application differences.

Technical Context

The MAX144BEPA+ implements a SAR architecture with integrated track-and-hold, supporting single-ended dual-channel conversion where CH0 and CH1 alternate automatically after power-on reset. Channel selection is controlled via CS/SHDN toggling, and the device operates in either internal clock mode (2MHz oscillator, SCLK high at CS/SHDN fall) or external clock mode (100kHz–2.17MHz, SCLK low at CS/SHDN fall).

It requires an external reference (0 to VDD + 50mV range, ≥18kΩ input resistance), supports 12-bit MSB-first serial output with channel ID bit, and provides 7.4µs conversion time with 2.5µs wake-up from shutdown. Input protection diodes clamp analog inputs to GND − 300mV and VDD + 300mV, while DC accuracy includes ±3 LSB gain error and ±3 LSB offset error over temperature.

Key Specifications

Pinout & Package

MAX144BEPA+ is housed in an 8-pin plastic DIP (dual in-line package) with 0.3-inch body width and through-hole mounting. Pin spacing is 0.1 inch, compatible with standard PCB layouts and socketing for prototyping and testing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX144BEPA+, MAX145BEPA+ offers differential input capability at identical packaging and power profile but sacrifices dual independent channel operation, while ADS7822U trades built-in track-and-hold and channel management for raw speed - making MAX144BEPA+ optimal for compact, low-maintenance dual-sensor systems.

Availability

MAX144BEPA+ is available at Aetrix Electronics and suitable for battery-powered instrumentation, isolated data acquisition, and process-control monitoring requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX144BEPA+ 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 industrial, medical, and communications applications.

The MAX144/MAX145 product line delivers ultra-low-power, serial-output 12-bit SAR ADCs optimized for space-constrained, energy-sensitive systems where dual-channel sampling and fast wake-up are essential.

FAQ

What is the maximum sampling rate of the MAX144BEPA+?

The MAX144BEPA+ achieves a maximum sampling rate of 108ksps under specified conditions (VDD = +3.6V, fSCLK = 2.17MHz, 16 clocks/conversion). This rate is sustained with full 12-bit resolution and meets timing requirements for both internal and external clock modes. At lower throughput rates, the device automatically reduces current consumption - e.g., 100µA at 10ksps and 10µA at 1ksps - enabling adaptive power management in the MAX144BEPA+ design.

Does the MAX144BEPA+ require an external reference voltage?

Yes, the MAX144BEPA+ requires an external reference voltage applied to the REF pin. The reference must be stable, capable of delivering ≥250µA DC load current, and have output impedance ≤10Ω. A 0.1µF ceramic capacitor is mandatory at the REF pin for noise suppression. The MAX144BEPA+ supports reference voltages from 0V up to VDD + 50mV, allowing flexibility in full-scale range selection - for example, 2.5V or 4.096V references are commonly used to match system scaling requirements.

What is the function of the CS/SHDN pin on the MAX144BEPA+?

The CS/SHDN pin on the MAX144BEPA+ serves a dual role: it acts as an active-low chip-select input and an active-high shutdown control. When pulled high, the MAX144BEPA+ enters shutdown mode with typical current draw of 0.2µA. A falling edge on CS/SHDN wakes the device, initiates track mode, and starts conversion - its state at the falling edge also selects clock mode (high = internal, low = external). This dual functionality eliminates the need for separate enable and select lines in the MAX144BEPA+ interface.

Can the MAX144BEPA+ interface directly with a microcontroller SPI port?

Yes, the MAX144BEPA+ is fully compatible with standard SPI, QSPI, and MICROWIRE interfaces. It operates with CPOL = 0 and CPHA = 0, and DOUT transitions on the falling edge of SCLK while data is sampled on the rising edge. The MAX144BEPA+ outputs a 16-bit serial stream (three leading 1s, CHID, then 12 data bits) - requiring two 8-bit reads to retrieve the full result. No level-shifting or protocol translation is needed for direct connection to most 3.3V or 5V microcontrollers.

What is the operating temperature range for the MAX144BEPA+?

The MAX144BEPA+ is rated for operation from -40°C to +85°C, as confirmed by its ordering code suffix "E" (e.g., MAX144BEPA+). This extended industrial temperature range is validated across all key specifications including INL (±1 LSB), gain error (±3 LSB), and supply current behavior. The device uses a plastic DIP package (P8-1) with lead finish suitable for wave or reflow soldering, and is designed for reliable performance in demanding environments such as factory automation and outdoor telemetry systems.