Analog Devices Inc./Maxim Integrated MAX6324EUT46

Overview

MAX6324EUT46 from Maxim Integrated is a microprocessor supervisory circuit with windowed (min/max) watchdog timer, open-drain RESET output, and factory-trimmed 4.63V reset threshold (±2.5% accuracy). It monitors VCC down to +1.2V, asserts RESET low on undervoltage or manual reset, and pulses WDPO low for 1ms upon fast/slow watchdog timeout faults. Used in automotive engine control units for fault-tolerant boot sequencing and runtime supervision.

For engineers reviewing the MAX6324EUT46 datasheet, MAX6324EUT46 pinout, MAX6324EUT46 application, or MAX6324EUT46 equivalent, key selection criteria include its 4.63V reset threshold, SOT23-6 open-drain RESET, 1ms WDPO pulse width, -40°C to +125°C operation, and compatibility with bidirectional µP reset pins in safety-critical embedded systems.

Technical Context

The MAX6324EUT46 implements a dual-window watchdog architecture: fast timeout (tWD1 = 15ms min / 15ms max) and slow timeout (tWD2 = 60s min / 90s max), both laser-trimmed and temperature-stable. Its VCC monitor uses a precision bandgap reference and comparator with guaranteed reset assertion down to VCC = +1.2V.

RESET is open-drain with 3.2mA sink capability at VCC = 4.25V; WDPO is open-drain with identical voltage rating and 1ms pulsed fault indication. MR input includes internal pullup and 100ns glitch immunity, requiring only a 1µs minimum low pulse to trigger reset.

Key Specifications

Pinout & Package

MAX6324EUT46 is housed in a 6-pin SOT23-6 package (JEDEC MO-178AA), 2.9mm × 1.6mm × 1.1mm, surface-mount, lead-free compatible.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6324EUT44, MAX6324EUT46 offers higher reset threshold for robust +5V rail supervision; compared with TPS3808G33DBVR, it delivers certified windowed watchdog functionality essential for functional safety architectures-making MAX6324EUT46 the only option meeting ASIL-B timing integrity requirements.

Availability

MAX6324EUT46 is available at Aetrix Electronics and suitable for automotive engine control units, industrial PLC modules, medical infusion pump controllers, avionics sensor interfaces, and safety-critical embedded systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6324EUT46 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, with emphasis on reliability, low power, and high integration.

The MAX6323/MAX6324 product line delivers fault-tolerant microprocessor supervision with windowed watchdog timers, targeting safety-critical embedded systems where deterministic reset and timing violation detection are mandatory.

FAQ

What is the exact reset threshold voltage of MAX6324EUT46 and how is it trimmed?

The MAX6324EUT46 features a factory-laser-trimmed reset threshold of 4.63V with ±2.5% accuracy over -40°C to +125°C. This value is permanently set during wafer test and corresponds to the "46" suffix in the part number per Maxim's ordering guide. No external components are needed to achieve this precision, eliminating drift and tolerance stacking in +5.0V supply monitoring applications.

Does MAX6324EUT46 support bidirectional microcontroller reset pins?

Yes, MAX6324EUT46 supports bidirectional µP reset pins via its open-drain RESET output. When paired with a single pullup resistor, it allows either the MAX6324EUT46 or the µP to assert reset-enabling shared reset bus architectures common in Motorola 68HC11 and ARM Cortex-M based designs without additional logic.

What are the watchdog timeout periods configured in MAX6324EUT46?

MAX6324EUT46 is configured with "E" suffix watchdog timing: fast timeout window of 15ms (min/max), and slow timeout window of 60s (min) to 90s (max). These values are laser-trimmed and stable over temperature, enabling precise detection of both rapid software loops and prolonged execution stalls.

Can MAX6324EUT46 operate reliably below 2.0V supply voltage?

Yes, MAX6324EUT46 guarantees valid RESET assertion down to VCC = +1.2V, and its supply current remains at 23µA typical even at VCC = 2.5V. This enables robust supervision during deep brownout conditions where many competing supervisors cease functioning or produce indeterminate outputs.

How does the WDPO output behave when RESET is asserted?

WDPO is inactive (high-impedance) whenever RESET is asserted low. The MAX6324EUT46 design ensures WDPO only pulses low for 1ms upon fast/slow watchdog faults when RESET is high-preventing conflicting signals and enabling clean separation between power-fault reset and software-execution fault reporting.