Analog Devices Inc./Maxim Integrated MAXQ7667AACM+T

Overview

MAXQ7667AACM+T from Maxim Integrated is a 16-bit RISC microcontroller-based ultrasonic distance-measuring SoC optimized for large-range, weak-signal, and multi-target time-of-flight applications. It integrates a programmable burst generator (25–100 kHz), echo reception path with 0.7 µV_RMS input-referred noise LNA, 16-bit sigma-delta ADC, digital bandpass/lowpass filters, and an embedded MAXQ20 core - all operating across –40°C to +125°C in a 48-pin LQFP package.

For engineers reviewing the MAXQ7667AACM+T datasheet, MAXQ7667AACM+T pinout, MAXQ7667AACM+T application, or MAXQ7667AACM+T equivalent, key selection criteria include its ultrasonic signal chain SNR, autonomous echo parameter adaptation, triple-supply operation (+2.5V/+3.3V/+5V), LIN/UART interface, and integrated 5-channel 12-bit SAR ADC with 250 ksps sampling rate.

Technical Context

The MAXQ7667AACM+T implements a closed-loop smart sensing architecture: its embedded 16-bit MAXQ20 microcontroller dynamically adjusts burst frequency and echo reception parameters per transmission based on real-time environmental feedback. Digital filtering (bandpass and lowpass) and burst synthesis operate autonomously without CPU intervention, freeing the core for optimization, diagnostics, and communication.

Its analog front end features dual ADC paths - a 16-bit sigma-delta ADC for echo digitization (80 × f_BPF sampling rate) and a separate 5-channel 12-bit SAR ADC (250 ksps) - both supported by internal voltage references (2.5 V ±1%) and configurable external reference inputs. Power management includes three independent linear regulators (REG2P5, REG3P3, GATE5-controlled DVDDIO) enabling single- or multi-rail operation from +2.5V to +65V.

Key Specifications

Pinout & Package

MAXQ7667AACM+T is housed in a 48-pin LQFP (7 mm × 7 mm, 0.5 mm pitch) package with exposed thermal pad. Pin functions are validated per Maxim's official pin description table (Rev 1, July 2009). Key terminal groups include dedicated echo inputs (ECHOP/ECHON), burst output (BURST), analog supplies (AVDD/AGND), digital I/Os (P0.x/P1.x), and regulator outputs (REG2P5/REG3P3/GATE5).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultrasonic distance-measuring applications.

Compared with TIDA-01385 and STSPIN32F0B, the MAXQ7667AACM+T uniquely integrates the complete ultrasonic signal chain - from burst generation and low-noise echo amplification to 16-bit digitization and envelope demodulation - within a single AEC-Q100-qualified package, reducing system-level design risk and validation effort.

Availability

MAXQ7667AACM+T is available at Aetrix Electronics and suitable for automotive parking assist, industrial tank level monitoring, vehicle security proximity sensing, and handheld ultrasonic distance meter applications requiring stable component supply over extended product lifecycles.

Supply support for MAXQ7667AACM+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 semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, automotive, and communications markets.

The MAXQ7667AACM+T belongs to Maxim's MAXQ ultrasonic SoC product line, designed specifically to replace multi-chip ultrasonic sensing subsystems with a single, temperature-resilient, LIN-enabled device for automotive and industrial time-of-flight applications.

FAQ

What is the primary function of the MAXQ7667AACM+T in ultrasonic sensing systems?

The MAXQ7667AACM+T serves as a complete time-of-flight ultrasonic distance-measuring system-on-a-chip. It integrates a programmable burst generator, low-noise echo receiver with 0.7 µV_RMS input-referred noise, 16-bit sigma-delta ADC, digital filters, and a 16-bit MAXQ20 microcontroller - enabling autonomous echo parameter optimization and high-accuracy ranging without external signal conditioning components. The MAXQ7667AACM+T is engineered to replace discrete analog front ends and general-purpose MCUs in demanding ultrasonic applications.

Does the MAXQ7667AACM+T support automotive LIN communication?

Yes, the MAXQ7667AACM+T includes a hardware UART with LIN 2.0 compliance, supporting data rates from 1 kbps to 20 kbps. Its TXEN pin directly controls external LIN transceivers, and the integrated protocol engine handles synchronization, checksum, and sleep/wake framing - eliminating software overhead. This makes the MAXQ7667AACM+T suitable for automotive parking assist modules that require direct integration into vehicle LIN networks without additional interface ICs.

How does the MAXQ7667AACM+T handle power supply variations in industrial environments?

The MAXQ7667AACM+T supports three native supply domains (+2.5V DVDD, +3.3V AVDD, +5V DVDDIO) and includes on-chip regulators: REG2P5 (+2.5V), REG3P3 (+3.3V), and GATE5 (controls external pass transistor for +5V rail). When powered from a single +8V to +65V source, GATE5 drives an external transistor to generate stable DVDDIO - enabling operation in wide-input industrial bus systems. Supply supervisors monitor all rails and generate interrupts or reset events below threshold voltages, ensuring robustness against brownouts.

Can the MAXQ7667AACM+T operate without an external crystal?

Yes, the MAXQ7667AACM+T includes an internal 13.5 MHz RC oscillator with ±10.5% initial accuracy and 700 ppm temperature drift, sufficient for non-timing-critical functions like UART communication or background processing. However, for precise ultrasonic burst generation and echo timing, the device relies on its crystal oscillator (4–16 MHz) or external clock input. The PLL synthesizes stable frequencies for both burst and ADC clocks - so crystal-free operation degrades ranging accuracy and is not recommended for production time-of-flight systems.

What analog inputs does the MAXQ7667AACM+T support beyond ultrasonic echo signals?

In addition to the differential ECHOP/ECHON echo inputs, the MAXQ7667AACM+T features a 5-channel 12-bit SAR ADC with 250 ksps sampling rate. Inputs AIN0–AIN4 support single-ended or differential measurements (AIN0/AIN1, AIN2/AIN3 pairs), with programmable gain and internal 2.5 V reference (or external 1.0–3.3 V reference). These channels are commonly used for monitoring transducer temperature, supply voltages, ambient pressure, or other system-level analog signals - all processed concurrently with ultrasonic echo analysis by the same MAXQ7667AACM+T die.