Analog Devices Inc./Maxim Integrated MAX6324EUT29-T

Overview

MAX6324EUT29-T from Maxim Integrated is an open-drain microprocessor supervisory circuit with windowed (min/max) watchdog, 2.93V ±2.5% reset threshold, 100ms minimum reset timeout, and guaranteed RESET validity down to VCC = +1.2V. It monitors +3.3V digital systems in automotive engine control units, industrial PLCs, and medical infusion pumps.

For engineers reviewing the MAX6324EUT29-T datasheet, MAX6324EUT29-T pinout, MAX6324EUT29-T application, or MAX6324EUT29-T equivalent, key selection criteria include its factory-trimmed E-window watchdog (fast timeout: 15ms min / slow timeout: 60ms min), SOT23-6 open-drain RESET/WDPO outputs, -40°C to +125°C operation, and AEC-Q100-compatibility path via /V variants.

Technical Context

The MAX6324EUT29-T implements a dual-threshold watchdog that detects both fast faults (WDI falling edges <15ms apart) and slow faults (no WDI edge >60ms), with WDPO pulsing low for 1ms on fault detection. Its reset comparator guarantees valid output down to VCC = +1.2V, enabling robust brownout recovery in noisy automotive environments.

It uses laser-trimmed internal references for ±2.5% reset threshold accuracy across temperature and features debounced MR input with 1μs minimum pulse width and 100ns glitch immunity. The open-drain RESET and WDPO outputs support level-shifting and bidirectional μP reset interfaces without external pullup conflicts.

Key Specifications

Pinout & Package

MAX6324EUT29-T is housed in a 6-pin SOT23 package (package code U6+1A, outline 21-0058), with 1.6mm × 2.9mm footprint and 0.95mm height, suitable for space-constrained PCB layouts in automotive modules and portable medical devices.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6324EUT29-T, MAX6324EUT26-T offers lower reset voltage for 2.5V rails but same timing precision, while TLV803EB29DBVR reduces pin count and cost at the expense of windowed watchdog functionality-making it unsuitable for ASIL-B or SIL-2 systems requiring dual-fault detection.

Availability

MAX6324EUT29-T is available at Aetrix Electronics and suitable for automotive engine control units, industrial programmable logic controllers, and medical infusion pump designs requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6324EUT29-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 medical applications.

The MAX6324 series targets high-reliability embedded systems requiring certified supervision-specifically engineered for AEC-Q100-compliant automotive modules and safety-critical industrial controls where deterministic reset and dual-threshold watchdog behavior are mandatory.

FAQ

What is the exact reset threshold voltage of MAX6324EUT29-T and how is it trimmed?

The MAX6324EUT29-T has a nominal reset threshold of 2.93V with ±2.5% accuracy over -40°C to +125°C. This value is achieved through factory laser trimming of internal voltage references, eliminating post-manufacture calibration. The "29" suffix directly corresponds to the 2.85V–3.00V threshold range per the Reset Threshold Range table in the datasheet, and the tolerance is guaranteed across temperature without derating.

Does MAX6324EUT29-T support windowed watchdog functionality, and what are its timeout values?

Yes, MAX6324EUT29-T implements a true min/max (windowed) watchdog. The "E" suffix specifies fast timeout ≥15ms and slow timeout ≥60ms. These are factory-trimmed laser settings-not user-programmable-and detect both premature WDI edges (faster than 15ms) and delayed edges (slower than 60ms). WDPO pulses low for 1ms upon either fault condition, independent of the RESET signal.

How does the open-drain RESET output of MAX6324EUT29-T differ from the push-pull version in MAX6323?

The MAX6324EUT29-T features an open-drain RESET output, requiring an external pullup resistor to any supply up to +6V. This enables bidirectional reset interfaces (e.g., with Motorola 68HC11) and level shifting between monitored and reset logic supplies. In contrast, the MAX6323 uses a push-pull output that actively drives high/low without external components-but cannot share a reset bus with other open-drain devices.

Can MAX6324EUT29-T operate reliably during deep brownout conditions?

Yes, MAX6324EUT29-T guarantees valid RESET assertion down to VCC = +1.2V, unlike many supervisors that fail below 1.8V. This ensures deterministic reset behavior during gradual power collapse-critical in automotive stop-start systems and battery-backed medical devices. Below +1.2V, the output enters high-impedance state, but the 100ms timeout guarantee holds across the full operating range.

What is the purpose of the WDPO pin on MAX6324EUT29-T, and how should it be used in system design?

The WDPO (Watchdog Pulse Output) pin on MAX6324EUT29-T is an open-drain output that pulses low for 1ms upon detection of fast or slow watchdog faults. It is designed to feed diagnostic interrupts or trigger secondary safety monitors-distinct from RESET, which handles full system restart. System designers connect WDPO to an NMI or GPIO interrupt pin, using a pullup resistor to match the target logic supply, enabling real-time fault logging without resetting critical state.