Analog Devices Inc./Maxim Integrated MAX11122ATI+T

Overview

The MAX11122ATI+T from Analog Devices is a 12-bit, 1 Msps, low-power serial SAR ADC with external reference support, 1.5 MHz full-linear bandwidth, and integrated SampleSet™ channel sequencing. It operates from 2.35V to 3.6V, consumes only 5.4 mW at full speed, and features flexible analog input configuration (single-ended, pseudo-differential, or fully differential) for high-accuracy data acquisition in space-constrained industrial sensors.

For engineers reviewing the MAX11122ATI+T datasheet, MAX11122ATI+T pinout, MAX11122ATI+T application, or MAX11122ATI+T equivalent, key selection criteria include its 12-bit resolution with ±1 LSB INL/DNL, 70 dB SINAD at 250 kHz, 16 MHz SPI-compatible interface, 28-pin TQFN package, and support for both internal clock (with FIFO/averaging) and external clock (with SampleSet programmable sequencing).

Technical Context

The MAX11122ATI+T implements a successive-approximation register (SAR) architecture with true differential track-and-hold, enabling simultaneous sampling of up to 4 analog input channels. Its dual-clock operation supports internal clock mode (with 16-entry FIFO and configurable averaging) and external clock mode (with SampleSet™-a user-defined 256-step channel sequencer that offloads microcontroller overhead).

Analog input flexibility includes software-selectable bipolar ranges (±VREF+/2 or ±VREF+), channel-to-channel offset matching of ±0.5 LSB, and crosstalk rejection of –88 dB. The device uses separate analog (VDD) and digital I/O (OVDD) supplies (1.5V–3.6V), ensuring robust noise isolation and compatibility with 1.8V/2.5V/3.3V logic systems.

Key Specifications

Pinout & Package

MAX11122ATI+T is housed in a 28-pin, 5 mm × 5 mm, exposed-pad TQFN package (package code T2855+3, outline 21-0140). The exposed pad (EP) must be soldered to GND for thermal performance and signal integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed, low-power SAR ADC applications.

Compared with ADS8860IRGET and AD7476ARTZ-REEL7, the MAX11122ATI+T uniquely combines 12-bit accuracy, 4-channel flexibility, SampleSet™ sequencing, and 5.4 mW power in a single 28-pin TQFN - making it optimal for compact, intelligent sensor nodes requiring autonomous multichannel acquisition.

Availability

MAX11122ATI+T is available at Aetrix Electronics and suitable for industrial sensor nodes, automotive battery monitors, portable medical devices, and high-speed closed-loop control systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX11122ATI+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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The MAX11122ATI+T belongs to the MAX11120–MAX11128 family of low-power, high-speed SAR ADCs designed specifically for battery-operated and thermally constrained data acquisition systems demanding precision, flexibility, and minimal MCU overhead.

FAQ

What is the maximum sampling rate supported by the MAX11122ATI+T?

The MAX11122ATI+T supports a maximum sampling rate of 1 Msps (1 million samples per second) in both internal and external clock modes. At this rate, conversion time is 1000 ns in external clock mode (16 MHz SCLK) and 5.9 µs in internal clock mode. This enables real-time capture of signals up to 500 kHz while maintaining full 12-bit resolution and no pipeline delay.

Does the MAX11122ATI+T require an external reference voltage?

Yes, the MAX11122ATI+T requires an external differential reference: REF+ accepts 1V to VDD, and REF–/AIN15 serves as the reference return. It does not include an internal reference. A stable external reference (e.g., 2.5V) is mandatory for ratiometric or absolute measurements, and REF+ must be bypassed with a 0.47 µF capacitor to GND per the datasheet layout guidelines.

How many analog input channels does the MAX11122ATI+T support?

The MAX11122ATI+T supports 4 analog input channels (AIN0–AIN3), consistent with its designation as the 4-channel variant in the MAX11120–MAX11128 family. Pin configuration confirms dedicated AIN0–AIN3 inputs; AIN14 and AIN15 are not bonded out in this variant and are reserved for higher-channel versions (e.g., MAX11126/28).

What is the purpose of the SampleSet™ feature in the MAX11122ATI+T?

The SampleSet™ feature in the MAX11122ATI+T is a user-programmable 256-step analog input channel sequencer that operates in external clock mode. It allows autonomous, non-repeating channel sequences (e.g., AIN0→AIN2→AIN1→AIN3→repeat) without MCU intervention, reducing communication overhead and system noise - especially valuable in multichannel sensor fusion applications where timing determinism and low CPU load are critical.

Is the MAX11122ATI+T compatible with standard SPI interfaces?

Yes, the MAX11122ATI+T features a 16 MHz, 3-wire SPI-compatible serial interface (CS, SCLK, DIN/DOUT) that directly connects to standard SPI, QSPI™, and MICROWIRE® controllers without external logic. It supports SPI Mode 0 (CPOL = 0, CPHA = 0), with data latched on SCLK rising edge (DIN) and output on falling edge (DOUT), and includes three-state DOUT for bus sharing.