Analog Devices Inc./Maxim Integrated MAX6324AUT26-T

Overview

MAX6324AUT26-T from Maxim Integrated is a microprocessor supervisory circuit with windowed (min/max) watchdog, open-drain RESET output, and factory-trimmed 2.63V reset threshold (±2.5% accuracy). It monitors +2.5V supply rails in automotive and industrial control systems, asserts RESET low on VCC drop or manual reset, and pulses WDPO low for 1ms upon fast/slow watchdog faults. Valid RESET operation guaranteed down to VCC = +1.2V.

For engineers reviewing the MAX6324AUT26-T datasheet, MAX6324AUT26-T pinout, MAX6324AUT26-T application, or MAX6324AUT26-T equivalent, key selection criteria include its 2.55V–2.70V reset threshold range, 100ms minimum reset timeout, SOT23-6 package compatibility, and open-drain WDPO/RESET outputs for bidirectional μP reset interfacing and NMI loopback.

Technical Context

The MAX6324AUT26-T implements a dual-window watchdog that detects both fast faults (WDI falling edges <15ms apart) and slow faults (no WDI edge >300ms), with timing factory-trimmed to "C" window (tWD1 = 10–15ms, tWD2 = 300–450ms). Its reset comparator guarantees valid output down to VCC = +1.2V and features ±2.5% threshold accuracy over –40°C to +125°C.

This variant uses an open-drain RESET output requiring external pullup, supports debounced MR input with 1μs minimum pulse width, and draws only 23µA typical supply current at 3.3V. All timing functions are laser-trimmed - no external components needed for reset or watchdog configuration.

Key Specifications

Pinout & Package

MAX6324AUT26-T is housed in a 6-pin SOT23 package (package code U6+1A, outline 21-0058), with 1.3mm × 0.8mm footprint and 0.95mm height - compatible with standard high-density PCB assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6324AUT26-T, MAX6324HUT26-T offers longer watchdog windows for less time-critical firmware, while TPS3808G33DBVR provides simpler reset-only functionality at lower cost but omits windowed watchdog supervision entirely - making it unsuitable for ISO 26262 or IEC 61508 safety architectures requiring dual-fault detection.

Availability

MAX6324AUT26-T is available at Aetrix Electronics and suitable for automotive engine control units, industrial PLC modules, medical infusion pump controllers, and railway signaling interface boards requiring stable component supply across extended temperature and long product lifecycles.

Supply support for MAX6324AUT26-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 - emphasizing reliability, low power, and AEC-Q100 qualification.

The MAX6324 series delivers microprocessor supervision with windowed watchdog functionality specifically for safety-critical embedded systems where deterministic fault detection and guaranteed reset behavior under brownout are mandatory design requirements.

FAQ

What is the exact reset threshold voltage of MAX6324AUT26-T?

The MAX6324AUT26-T has a factory-trimmed nominal reset threshold of 2.63V, with guaranteed range of 2.55V to 2.70V at –40°C to +125°C. This matches +2.5V supply rails with ±2.5% accuracy and is laser-trimmed - no external calibration required. The "26" suffix in MAX6324AUT26-T explicitly denotes this 2.63V threshold variant.

Does MAX6324AUT26-T support windowed watchdog functionality, and what are its timeout values?

Yes, MAX6324AUT26-T implements true windowed (min/max) watchdog supervision. With the "C" suffix, its fast timeout (tWD1) is 10–15ms and slow timeout (tWD2) is 300–450ms. These values are factory-laser-trimmed and specified over full temperature range - enabling detection of both premature and delayed WDI pulses in safety-critical firmware.

What is the function of the WDPO pin on MAX6324AUT26-T, and how should it be used?

The WDPO pin on MAX6324AUT26-T is an open-drain watchdog pulse output that asserts low for 1ms (typical) upon detecting either a fast or slow watchdog fault. It must be pulled up externally to any supply ≤+6V. Common use cases include triggering NMI interrupts or connecting to MR for automatic 100ms hard reset - as shown in Figure 10 of the MAX6324AUT26-T datasheet.

Can MAX6324AUT26-T operate reliably during deep brownout conditions?

Yes, MAX6324AUT26-T guarantees valid RESET output down to VCC = +1.2V - significantly below its 2.63V threshold. This ensures deterministic reset assertion even during severe brownout events. However, below +1.2V, the open-drain RESET output loses sink capability; for VCC = 0V validity, external pulldown is required (though not recommended for MAX6324AUT26-T due to open-drain architecture).

Is MAX6324AUT26-T qualified for automotive applications?

MAX6324AUT26-T is rated for –40°C to +125°C operation and meets AEC-Q100 stress test requirements for Grade 0 devices. While the base MAX6324AUT26-T part is not explicitly marked "/V", the identical "MAX6324HUT44/V+T" variant confirms Maxim's automotive qualification pathway. For full automotive compliance, specify MAX6324AUT26/V+T (lead-free, automotive-grade version).