Analog Devices Inc./Maxim Integrated MAX16998DAUA/V+T

Overview

MAX16998DAUA/V+T from Maxim Integrated is an AEC-Q100 qualified automotive-grade high-voltage microprocessor supervisory IC with windowed watchdog timer and dual open-drain outputs (RESET and ENABLE). It operates from 5V to 40V input, draws only 18µA typical quiescent current at +125°C, and features capacitor-adjustable reset timeout (1ms–116ms) and watchdog timeout (6.8ms–217ms), with a factory-set 75% window size for fault detection. It is used in automotive powertrain control units to monitor MCU health and trigger fail-safe switchover.

For engineers reviewing the MAX16998DAUA/V+T datasheet, MAX16998DAUA/V+T pinout, MAX16998DAUA/V+T application, or MAX16998DAUA/V+T equivalent, key selection criteria include its 75% window watchdog architecture, -40°C to +125°C operation, 8-pin µMAX package, RESETIN voltage monitoring capability, and compatibility with car battery supply rails and redundant system enable logic.

Technical Context

The MAX16998DAUA/V+T implements a factory-configured 75% window watchdog timer (tCW = 25% × tWP, tOW = 75% × tWP), where WDI falling edges outside the open window (too early or too late) assert RESET for tRESET. Its RESETIN input monitors external voltages via resistive divider with 1.235V threshold, while SRT and SWT pins use precision internal ramp currents (500nA typ) to set timeout periods linearly with external capacitors.

It delivers two independent open-drain outputs: RESET (18V max pullup, 0.4V low @ 0.4mA) and ENABLE (28V max pullup, 0.4V low @ 5mA), both asserted only when VIN > 1.1V. The device supports power-on/power-off reset sequencing, narrow-pulse immunity (WDI pulses <1µs ignored), and maintains functional integrity across full automotive temperature range without derating.

Key Specifications

Pinout & Package

MAX16998DAUA/V+T is housed in an 8-pin lead(Pb)-free µMAX® package (3mm × 3mm, 0.5mm pitch), RoHS-compliant and qualified for automotive use. Pin functions are validated per Maxim's official datasheet revision 5 (April 2019).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage watchdog supervisor applications.

Compared with MAX16998BAUA/V+, the MAX16998DAUA/V+T provides wider open-window tolerance for late-fault detection, improving robustness against timing jitter in long-loop firmware. Versus TLV809EADBZR, it adds full watchdog supervision, dual outputs, and automotive-grade voltage range - making it suitable for ASIL-B–capable systems where TLV809EADBZR falls short.

Availability

MAX16998DAUA/V+T is available at Aetrix Electronics and suitable for automotive powertrain control, ADAS domain controllers, and electric power steering systems requiring stable component supply across extended product lifecycles and rigorous environmental conditions.

Supply support for MAX16998DAUA/V+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 demanding industrial, automotive, and communications applications.

The MAX16997/MAX16998 family was engineered specifically for high-reliability automotive microprocessor supervision - delivering wide-input, low-I_Q, windowed watchdog, and AEC-Q100 compliance in compact µMAX packaging.

FAQ

What is the watchdog window configuration of the MAX16998DAUA/V+T?

The MAX16998DAUA/V+T features a factory-set 75% window watchdog timer, meaning the open window (tOW) occupies 75% of the total watchdog timeout period (tWP), while the closed window (tCW) occupies the remaining 25%. This configuration detects both early-fault (WDI edge in tCW) and late-fault (no edge within tWP) conditions. The MAX16998DAUA/V+T does not support user reconfiguration of the window ratio - it is fixed at 75% per device marking and datasheet specification.

Can the MAX16998DAUA/V+T monitor multiple voltage rails simultaneously?

The MAX16998DAUA/V+T has one dedicated high-impedance RESETIN input for external voltage monitoring via resistive divider, and no additional dedicated voltage sense inputs. It cannot monitor multiple rails concurrently. However, RESETIN can be connected to a node common to several rails (e.g., post-LDO output) or multiplexed using external analog switches - though such designs require careful validation of leakage, noise coupling, and timing impact on the 1.235V threshold accuracy.

What is the minimum recommended pullup voltage for the ENABLE output of the MAX16998DAUA/V+T?

The ENABLE output of the MAX16998DAUA/V+T requires a minimum pullup voltage of 2.25V, as specified in the Electrical Characteristics table. While the absolute maximum is 28V, using a pullup voltage near the lower bound (e.g., 2.5V–3.3V) is acceptable and commonly implemented to interface directly with 3.3V logic domains. Ensure the pullup resistor value allows ≥5mA sink capability at 0.4V output low voltage.

Does the MAX16998DAUA/V+T support power-on reset (POR) and power-down reset (PDR) functionality?

Yes, the MAX16998DAUA/V+T supports both power-on and power-down reset sequencing. On power-up, RESET asserts low once VIN exceeds 1.1V and remains low until RESETIN rises above its 1.235V threshold and the tRESET timer expires. On power-down, RESET asserts low when RESETIN falls below threshold and stays low until VIN drops below 1.1V. This behavior is explicitly documented in Figures 5 and 6 of the datasheet and applies to all MAX16998A/B/D variants including the MAX16998DAUA/V+T.

How does the MAX16998DAUA/V+T handle WDI signal noise or glitches?

The MAX16998DAUA/V+T provides inherent WDI glitch immunity: pulses narrower than 1µs are ignored, and the input features hysteresis (200mV) to reject noise near the 0.9V/2.25V logic thresholds. For enhanced robustness, Maxim recommends adding an RC low-pass filter (e.g., 12kΩ + 47pF) directly at the WDI pin. Layout best practices - short traces, isolation from noisy signals, and avoidance of probe loading - further minimize spurious triggering, as confirmed in the Layout Considerations section.