Analog Devices Inc./Maxim Integrated MAX6324CUT31-T

Overview

MAX6324CUT31-T from Maxim Integrated is an open-drain microprocessor supervisory IC with windowed (min/max) watchdog, 3.08V ±2.5% reset threshold, 15ms fast timeout and 300ms slow timeout, and guaranteed RESET validity down to VCC = +1.2V. It monitors power supply integrity and processor activity in automotive engine control units, industrial PLCs, and medical infusion pumps.

For engineers reviewing the MAX6324CUT31-T datasheet, MAX6324CUT31-T pinout, MAX6324CUT31-T application, or MAX6324CUT31-T equivalent, key selection criteria include its factory-trimmed dual-window watchdog timing, open-drain RESET/WDPO outputs compatible with bidirectional μP reset pins, low 23µA typical supply current, and AEC-Q100-qualified operation across –40°C to +125°C.

Technical Context

The MAX6324CUT31-T implements a laser-trimmed min/max watchdog architecture: it detects both fast faults (WDI falling edges <15ms apart) and slow faults (no WDI edge >300ms), pulsing WDPO low for 1ms on fault detection. Its reset comparator guarantees valid output down to VCC = +1.2V, enabling robust brownout recovery in systems with deep voltage droop.

This variant uses the 'C' watchdog suffix (15ms fast / 300ms slow timeout) and '31' reset threshold code (3.00V–3.15V nominal), configured at wafer level. The open-drain RESET output requires an external pullup and supports level-shifting across multiple supply domains, while MR input includes internal 50–85kΩ pullup and 100ns glitch immunity.

Key Specifications

Pinout & Package

MAX6324CUT31-T is housed in a 6-pin SOT23 package (package code U6+1A, outline 21-0058), with 1.3mm × 2.2mm footprint and 0.95mm height. Thermal resistance θJA = 115°C/W on multilayer board.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6324CUT31-T, MAX6324HUT31-T offers extended watchdog timing for less aggressive fault detection, while TLV809E30DBZR provides simpler, lower-cost reset-only supervision without windowed watchdog capability-making MAX6324CUT31-T optimal for safety-critical embedded systems requiring both precise voltage monitoring and dual-threshold software execution verification.

Availability

MAX6324CUT31-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 product lifecycles.

Supply support for MAX6324CUT31-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 and mixed-signal ICs for demanding industrial, automotive, and medical applications.

The MAX6324 series delivers AEC-Q100-qualified microprocessor supervision with windowed watchdog functionality, targeting safety-critical embedded systems where deterministic reset behavior and software execution integrity are mandatory.

FAQ

What is the exact reset threshold voltage of MAX6324CUT31-T and how is it trimmed?

The MAX6324CUT31-T has a nominal reset threshold of 3.08V with ±2.5% accuracy (3.00V to 3.15V) over –40°C to +125°C. This value is laser-trimmed at wafer level and permanently fixed for the '31' variant-no external adjustment is possible. The tolerance ensures reliable reset assertion in 3.3V systems despite supply ripple and temperature drift.

Does MAX6324CUT31-T support bidirectional microprocessor reset pins?

Yes, MAX6324CUT31-T supports bidirectional μP reset pins via its open-drain RESET output. When paired with a single external pullup resistor, both the MAX6324CUT31-T and the μP (e.g., Motorola 68HC11) can assert reset on the shared line-enabling hardware-initiated and software-initiated reset coordination without additional logic.

What are the watchdog timeout values for MAX6324CUT31-T and how are they selected?

MAX6324CUT31-T uses the 'C' watchdog suffix: 15ms minimum fast timeout (detects premature WDI pulses) and 300ms minimum slow timeout (detects missing WDI pulses). These values are factory-laser-trimmed and immutable-no external components or registers configure them. The 'C' designation is encoded directly into the part number.

Can MAX6324CUT31-T operate reliably during severe brownout conditions?

Yes, MAX6324CUT31-T guarantees valid RESET output down to VCC = +1.2V, ensuring deterministic reset assertion even during deep brownouts. Below +1.2V, the internal circuitry ceases sinking current-but above that threshold, the open-drain RESET remains fully functional and compliant with logic-level requirements for downstream μPs.

Is MAX6324CUT31-T qualified for automotive applications?

MAX6324CUT31-T is not explicitly AEC-Q100 qualified-only variants with '/V' suffix (e.g., MAX6324HUT44/V+T) carry that qualification. However, MAX6324CUT31-T operates across the same –40°C to +125°C temperature range and meets all electrical specifications required for under-hood automotive use; system-level qualification remains the customer's responsibility.