Analog Devices Inc./Maxim Integrated MAX11138ATI+T

Overview

MAX11138ATI+T from Maxim Integrated is a 10-bit, 500ksps, low-power, serial-output SAR ADC in a 28-pin TQFN (5mm × 5mm) package. It supports 8-channel single-ended or 4-channel fully differential analog inputs, operates from 2.35V–3.6V supply, consumes 4.2mW at full speed, and features SampleSet programmable channel sequencing and internal FIFO for high-speed sampling with flexible readout timing.

For engineers reviewing the MAX11138ATI+T datasheet, MAX11138ATI+T pinout, MAX11138ATI+T application, or MAX11138ATI+T equivalent, this page delivers verified technical context, real-world design meaning for key specs, validated pin functions, application-specific use cases, and two confirmed alternative parts with documented functional and application-level differences.

Technical Context

The MAX11138ATI+T implements a successive-approximation register (SAR) architecture with dual clock modes: internal clock (enabling FIFO buffering and on-chip averaging) and external clock (supporting SampleSet programmable channel sequencing). Its analog front-end allows per-channel configuration as single-ended, fully differential, or pseudo-differential with software-selectable bipolar input ranges (±VREF+/2 or ±VREF+).

It integrates a 16-entry FIFO, AutoShutdown™ for sub-µA shutdown current (2µA typical), and a 3-wire SPI/QSPI/MICROWIRE-compatible serial interface operating up to 8MHz. The device guarantees ±0.4 LSB INL and ±0.4 LSB DNL over –40°C to +125°C, with 61.7dB SINAD at 250kHz input frequency.

Key Specifications

Pinout & Package

MAX11138ATI+T is housed in a 28-pin, 5mm × 5mm, 0.5mm-pitch TQFN package with exposed pad (EP) requiring connection to GND for thermal and electrical performance. Pin functions are validated per Maxim's official datasheet Rev 1 (July 2012), Figure 15 (MAX11138 pin configuration) and Table 1 (Pin Description).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS8684IPWR and AD7928BRUZ, the MAX11138ATI+T uniquely balances 10-bit precision, ultra-low power (4.2mW), and intelligent on-chip features-SampleSet sequencing and FIFO-making it optimal for resource-constrained embedded systems requiring autonomous multichannel acquisition without CPU overhead.

Availability

MAX11138ATI+T is available at Aetrix Electronics and suitable for industrial sensor hubs, portable medical monitors, motor phase current monitoring, and smart energy metering requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX11138ATI+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) designs precision analog, mixed-signal, and power-management ICs for industrial, medical, and communications applications.

The MAX11135–MAX11143 family-including MAX11138ATI+T-is engineered for low-power, high-speed multichannel data acquisition in space-constrained, battery-operated, or thermally demanding environments.

FAQ

What is the maximum sampling rate supported by the MAX11138ATI+T?

The MAX11138ATI+T supports a maximum conversion rate of 500ksps in both internal and external clock modes. At this rate, conversion time is 2µs (externally clocked, 8MHz SCLK) or 5.9µs (internally clocked). This enables accurate digitization of signals up to 250kHz while maintaining full 10-bit linearity and 61.7dB SINAD performance.

Does the MAX11138ATI+T support differential input configurations?

Yes, the MAX11138ATI+T supports fully differential input pairs (4 channels), pseudo-differential inputs relative to a common input (8 channels), and single-ended inputs (8 channels). Each channel can be independently configured via control registers, and differential mode uses the internal track-and-hold for true simultaneous sampling across both inputs of a pair.

How does the SampleSet feature work in the MAX11138ATI+T?

The SampleSet feature in the MAX11138ATI+T allows users to define and load a custom channel sequence (up to 256 steps) into on-chip memory. Once loaded, the ADC autonomously cycles through the programmed order without host intervention-reducing MCU communication overhead and system-level noise during multichannel acquisition.

What power-saving modes does the MAX11138ATI+T offer?

The MAX11138ATI+T offers AutoShutdown™ mode (2µA typical), AutoStandby (0.9–1.5mW depending on supply), and full shutdown. In AutoShutdown, the device wakes up automatically upon CNVST assertion or serial activity, achieving sub-microsecond wake-up latency-critical for duty-cycled sensor nodes using the MAX11138ATI+T.

Is an external reference required for the MAX11138ATI+T to operate?

Yes, the MAX11138ATI+T requires an external differential reference applied to REF+ (1V to VDD) and REF− (–0.3V to +1V). It does not include an internal reference. This design enables ratiometric measurements, improved PSRR, and compatibility with precision external references such as the MAX6126 or REF5025, directly supporting metrology-grade accuracy requirements.