Analog Devices Inc./Maxim Integrated MAX6374KA+T

Overview

MAX6374KA+T 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 watchdog output with 1ms pulse width, operates from +2.5V to +5.5V, draws only 10–22µA supply current over –40°C to +125°C, and supports startup delay and timeout periods selectable via SET0/SET1/SET2 pins - used in automotive ECUs and industrial controllers for fail-safe reset signaling.

For engineers reviewing the MAX6374KA+T datasheet, MAX6374KA+T pinout, MAX6374KA+T application, or MAX6374KA+T equivalent, key selection criteria include its 1ms push-pull WDO pulse, 200µs–60s programmable startup delay, 30µs–10s watchdog timeout range, AEC-Q100 qualification (via /V+ suffix), and SOT23-8 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6374KA+T implements a precision analog/digital hybrid watchdog timer with BiCMOS process technology. Its internal timing engine uses pin-strapped logic (SET0/SET1/SET2) to configure both startup delay and watchdog timeout independently - unlike fixed-timer supervisors, enabling dynamic adaptation to boot sequence length and runtime code execution windows.

It features a dedicated transition detector on WDI that clears the timer on any valid rising or falling edge ≥100ns wide, ignores transitions during WDO assertion and internal 300µs setup time, and delivers a deterministic 1ms active-low push-pull pulse on timeout - eliminating external pull-up components required by open-drain variants like MAX6373KA+T.

Key Specifications

Pinout & Package

MAX6374KA+T is housed in an 8-pin SOT23 package (package code K8SN+1, outline 21-0078), RoHS-compliant with lead(Pb)-free terminations. The package measures 2.9mm × 1.6mm × 1.1mm and supports reflow soldering per JEDEC J-STD-020 (260°C peak).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6373KA+T and TPS3808G33DBVR, MAX6374KA+T uniquely delivers push-pull WDO with 1ms pulse width, full pin-selectable startup/timeout ranging from microseconds to tens of seconds, and AEC-Q100-aligned reliability - making it optimal for next-generation automotive and industrial safety systems requiring configurability and deterministic reset timing.

Availability

MAX6374KA+T is available at Aetrix Electronics and suitable for automotive ECU development, industrial PLC upgrades, and medical device certification programs requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for MAX6374KA+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 communications applications.

The MAX6369–MAX6374 family was engineered specifically for robust microprocessor supervision in harsh environments - delivering pin-configurable timing, ultra-low power, and extended temperature operation without external components.

FAQ

What is the watchdog output type and pulse width of the MAX6374KA+T?

The MAX6374KA+T features a push-pull, active-low watchdog output (WDO) with a guaranteed minimum pulse width of 1ms. Unlike open-drain variants such as MAX6373KA+T, this eliminates the need for an external pull-up resistor and ensures clean, rail-to-rail voltage transitions - critical for reliable reset signaling into modern microcontrollers with strict input threshold requirements. This behavior is inherent to the MAX6374KA+T silicon design and applies across its full operating temperature and voltage range.

How do the SET0, SET1, and SET2 pins configure timing on the MAX6374KA+T?

The SET0, SET1, and SET2 pins on the MAX6374KA+T are logic inputs (tied to VCC or GND) that jointly select eight distinct combinations of startup delay and watchdog timeout periods. For example, SET2=0/SET1=0/SET0=0 yields 3ms startup delay and 3ms timeout, while SET2=1/SET1=1/SET0=1 gives 60s startup and 10s timeout. These settings take effect after a 300µs internal setup time, and changing them dynamically allows runtime adaptation - a capability confirmed in the MAX6374KA+T datasheet's "Selecting Device Timing" section.

Is the MAX6374KA+T AEC-Q100 qualified?

The MAX6374KA+T itself is not explicitly marked as AEC-Q100 qualified in its ordering code; however, the /V+ variant (MAX6374KA/V+T) is AEC-Q100 Rev H qualified. Since both share identical die, package, and test flow - differing only in screening and marking - MAX6374KA+T is widely deployed in automotive applications where qualification traceability is managed at the system level. Designers using MAX6374KA+T in automotive contexts should verify qualification alignment with their Tier 1 supplier requirements.

What is the minimum watchdog timeout period supported by the MAX6374KA+T?

The MAX6374KA+T supports a minimum watchdog timeout period of 30µs - achieved when SET2=0, SET1=0, and SET0=0. This value is specified in the Electrical Characteristics table under "Watchdog Timeout Period (tWD)" for MAX6373/MAX6374 devices and is guaranteed over the full –40°C to +125°C operating temperature range. Such fine-grained timing enables supervision of high-speed real-time control loops, including motor commutation and digital power conversion tasks.

Does the MAX6374KA+T require external passive components for basic operation?

No, the MAX6374KA+T requires no external passive components for core watchdog functionality. Its internal oscillator, transition detector, and timing logic are fully self-contained. A 0.1µF ceramic bypass capacitor between VCC and GND is recommended (and specified in the datasheet) for noise immunity in electrically noisy environments, but this is not mandatory for functional operation - only for robustness. No resistors, capacitors, or crystals are needed to configure or operate the MAX6374KA+T's watchdog timer.