Analog Devices Inc./Maxim Integrated MAX6370KA/V+

Overview

MAX6370KA/V+ from Maxim Integrated is a pin-selectable watchdog timer IC designed to supervise microprocessor activity in safety-critical embedded systems. It features push-pull active-low WDO output with 1ms pulse width, operates from +2.5V to +5.5V, draws only 10µA typical supply current at -40°C to +125°C, and supports eight selectable watchdog timeout periods ranging from 1ms to 60s. It is used in automotive ECUs to detect firmware hangs and trigger safe-state recovery.

For engineers reviewing the MAX6370KA/V+ datasheet, MAX6370KA/V+ pinout, MAX6370KA/V+ application, or MAX6370KA/V+ equivalent, this page delivers verified timing parameters, automotive-grade qualification status, pin-configuration logic mapping, and real-world supervision use cases for industrial and automotive μP monitoring.

Technical Context

The MAX6370KA/V+ implements a dual-phase supervision architecture: an initial startup delay (1ms–60s, pin-selectable via SET0–SET2) followed by a normal watchdog timeout period (1ms–60s, same pin mapping). Its internal transition detector clears the timer on any valid rising or falling edge at WDI ≥100ns wide, ignoring transitions during WDO assertion and a 300µs internal setup window after power-up or setting changes.

This device uses BiCMOS process technology (1500 transistors), provides push-pull WDO output capable of sinking 1.2mA at 0.3V low-level voltage, and supports dynamic timing reconfiguration without power cycling - enabling adaptive supervision in evolving firmware states.

Key Specifications

Pinout & Package

MAX6370KA/V+ is housed in an 8-pin SOT23 package (package code K8SN+1), measuring 2.9mm × 1.6mm × 1.1mm, with gull-wing leads and RoHS-compliant lead-free finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar watchdog timer applications.

Compared with MAX6372KA+T and TPS3808G33DBVR, the MAX6370KA/V+ uniquely combines AEC-Q100 qualification, full pin-selectable startup + timeout timing, push-pull output, and wide 2.5V–5.5V supply - making it the only option qualified for automotive under-hood deployment with adaptive supervision capability.

Availability

MAX6370KA/V+ is available at Aetrix Electronics and suitable for automotive ECU design, industrial PLC development, and telecom infrastructure projects requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6370KA/V+ 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 high-reliability ICs for automotive, industrial, and communications markets.

The MAX6369–MAX6374 family was engineered specifically for hardware-based microprocessor supervision in safety-critical systems - emphasizing configurability, low power, and AEC-Q100 compliance for automotive and industrial control.

FAQ

What is the watchdog output type and drive capability of the MAX6370KA/V+?

The MAX6370KA/V+ features a push-pull active-low watchdog output (WDO) capable of sinking 1.2mA at 0.3V (VCC > 2.7V) and 6mA at 0.4V (VCC > 4.5V). Unlike open-drain variants, it requires no external pull-up resistor and directly drives reset or interrupt inputs of microprocessors and FPGAs. This behavior is confirmed in the Functional Diagram and Electrical Characteristics table of the MAX6370KA/V+ datasheet.

Does the MAX6370KA/V+ support dynamic reconfiguration of watchdog timing during operation?

Yes, the MAX6370KA/V+ supports real-time timing reconfiguration: changing SET0–SET2 logic levels updates startup delay and timeout period without power cycling. After a 300µs internal setup time (tSETUP), the new timing parameters take effect - either immediately if WDO is deasserted, or after current WDO pulse completes if asserted. This capability is explicitly documented in the "Selecting Device Timing" section of the MAX6370KA/V+ datasheet.

Is the MAX6370KA/V+ qualified for automotive applications?

Yes, the MAX6370KA/V+ is AEC-Q100 qualified (Grade 0) for operation from -40°C to +125°C and is designated with the "/V+" suffix to indicate automotive qualification. It meets stress testing requirements for temperature cycling, humidity, and mechanical shock - making it suitable for engine control units, body control modules, and ADAS subsystems. This qualification is stated in the Benefits and Features section of the MAX6370KA/V+ datasheet.

What is the minimum required pulse width on the WDI input for the MAX6370KA/V+?

The MAX6370KA/V+ requires a minimum WDI pulse width of 100ns for reliable edge detection, as specified in the Electrical Characteristics table under "Watchdog Input Pulse Width (Note 2)". Pulses narrower than this may not be recognized, risking false timeout assertion. This parameter is independent of supply voltage and applies across the full -40°C to +125°C operating range of the MAX6370KA/V+.

How does the MAX6370KA/V+ handle power-up and initialization timing?

The MAX6370KA/V+ implements a two-stage timing sequence: first, an internal 300µs setup window (tSETUP) after power-up during which WDI transitions are ignored; second, a user-configurable startup delay (1ms–60s) before watchdog counting begins. Only after this startup delay expires does the device begin monitoring WDI for the selected timeout period. This behavior ensures robust initialization in systems with variable boot sequences and is fully detailed in Figure 1 and the Detailed Description section of the MAX6370KA/V+ datasheet.