Analog Devices Inc./Maxim Integrated MAX16997AAUA+T

Overview

MAX16997AAUA+T from Maxim Integrated is a high-voltage, low-quiescent-current microprocessor supervisory IC designed for automotive power monitoring and watchdog control. It features one open-drain ENABLE output, capacitor-adjustable watchdog timeout (tWP), EN input with car-battery-compatible threshold (1.235V), 5V–40V operating range, and AEC-Q100 qualification for under-hood applications.

For engineers reviewing the MAX169997AAUA+T datasheet, MAX16997AAUA+T pinout, MAX16997AAUA+T application, or MAX16997AAUA+T equivalent, key selection criteria include its single-ENABLE architecture (no RESET output), EN-triggered watchdog startup with 8× initial timeout extension, 18µA quiescent current at +125°C, and μMAX® 8-pin package compatibility with automotive thermal and voltage stress requirements.

Technical Context

The MAX16997AAUA+T implements a voltage-monitoring supervisory function where the EN input controls both watchdog enablement and reset threshold detection. Its watchdog timer starts only when EN rises above 1.235V, and the first timeout period is extended to 8×tWP - a feature critical for safe microcontroller boot sequencing in automotive systems.

Unlike the MAX16998 family, it omits RESET output and RESETIN input, relying solely on EN for supply monitoring and WDI for activity supervision. The internal ramp current source (500nA typ) charges external capacitors at SWT to set tWP, while timing accuracy is maintained across -40°C to +125°C via temperature-stable IRAMP and VPON references.

Key Specifications

Pinout & Package

MAX16997AAUA+T is housed in an 8-pin lead(Pb)-free µMAX® package (3mm × 3mm, 0.5mm pitch), optimized for space-constrained automotive ECUs and qualified per AEC-Q100 Grade 0 (-40°C to +125°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar supervisory applications.

Compared with MAX16998AAUA+T and TLV809EADBZR, MAX16997AAUA+T uniquely balances automotive-grade voltage range, ultra-low quiescent current, EN-gated watchdog startup, and minimal pin count - making it optimal for new automotive ECUs where ENABLE-driven redundancy is preferred over dual-output supervision.

Availability

MAX16997AAUA+T is available at Aetrix Electronics and suitable for automotive engine control, ADAS camera modules, body control units, and electric power steering systems requiring stable component supply across extended temperature and voltage stress conditions.

Supply support for MAX16997AAUA+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 solutions for automotive, industrial, and communications markets.

The MAX16997/MAX16998 product line was engineered specifically for automotive microprocessor supervision - delivering robust high-voltage monitoring, configurable watchdog timing, and AEC-Q100 reliability in compact µMAX packages.

FAQ

What is the primary function of the MAX16997AAUA+T in an automotive system?

The MAX16997AAUA+T serves as a high-voltage supervisory IC that monitors the vehicle's 12V supply via its EN input and verifies microcontroller software execution via the WDI signal. It asserts the ENABLE output after three consecutive WDI timeouts - triggering hardware-level fail-safe actions such as subsystem shutdown or redundancy switchover. Unlike dual-output variants, MAX16997AAUA+T provides ENABLE-only control optimized for simplified safety architectures.

Does the MAX16997AAUA+T have a RESET output?

No, the MAX16997AAUA+T does not include a RESET output. It generates only a single open-drain ENABLE signal. This distinguishes it from the MAX16998 family (e.g., MAX16998AAUA+T), which provides both RESET and ENABLE outputs. The absence of RESET simplifies design where the host MCU handles its own reset generation or where ENABLE-driven redundancy is sufficient for safety compliance.

How does the 8× initial watchdog timeout work on the MAX16997AAUA+T?

Each time the EN input voltage rises above the 1.235V threshold, the MAX16997AAUA+T initiates an extended watchdog timeout period equal to 8× the nominal tWP (set by the SWT capacitor). This extended window accommodates bootloader execution and MCU initialization before strict watchdog enforcement begins. If a valid WDI falling edge occurs during this period, the timeout reverts to normal tWP; otherwise, ENABLE asserts at the end of the 8× interval.

What is the maximum allowable voltage on the IN pin of the MAX16997AAUA+T?

The absolute maximum voltage rating for the IN pin of the MAX16997AAUA+T is +45V. This specification allows the device to survive automotive load-dump transients defined in ISO 7637-2 (up to +40V for 50ms), with margin for design safety. Operation remains fully specified from 5.0V to 40.0V, covering cold-crank (as low as 5V) through normal and transient battery conditions.

Is the MAX16997AAUA+T qualified for automotive use?

Yes, the MAX16997AAUA+T is AEC-Q100 qualified (Grade 0) and fully specified over the -40°C to +125°C ambient temperature range. It undergoes rigorous stress testing including HTOL, TC, UHAST, and ESD per AEC-Q100 Rev H, ensuring reliability in under-hood automotive environments. The "/V" suffix in some ordering codes denotes explicit automotive qualification, but MAX16997AAUA+T carries the same qualification regardless of suffix.