Analog Devices Inc./Maxim Integrated MAX6751KA50/V+T

Overview

MAX6751KA50/V+T from Analog Devices is a low-power microprocessor supervisory circuit with factory-trimmed 5.0V ±2% VCC reset threshold, adjustable dual-voltage monitoring (VCC + RESET IN), capacitor-adjustable reset timeout (5.7–9.5ms typical), watchdog select input (WDS) for 128× extended timeout, and AEC-Q100-qualified operation from –40°C to +125°C - used in automotive engine control units to ensure deterministic μP restart during voltage sags.

For engineers reviewing the MAX6751KA50/V+T datasheet, MAX6751KA50/V+T pinout, MAX6751KA50/V+T application, or MAX6751KA50/V+T equivalent, key selection criteria include its dual-supply monitoring capability, WDS-enabled watchdog scalability, push-pull/open-drain RESET output configurability, guaranteed RESET validity down to VCC = 1V, and SOT23-8 automotive-grade packaging.

Technical Context

The MAX6751KA50/V+T integrates two independent reset comparators: one factory-trimmed at 5.0V ±2% for VCC monitoring, and a second high-impedance adjustable comparator on RESET IN (1.235V threshold) enabling external resistor-divider-based monitoring of a second supply rail. It supports dual-voltage fault detection - RESET asserts if either VCC drops below 5.0V or RESET IN falls below its threshold.

Its watchdog architecture uses a single SWT capacitor to set base timeout (tWD = 4.94×10⁶ × CSWT), with WDS pin selecting normal mode (tWD) or extended mode (128×tWD). Unlike MAX6752/MAX6753, it lacks windowed watchdog logic and SET0/SET1 inputs - confirming it belongs to the MAX6746–MAX6751 variant group with scalable but non-windowed timing.

Key Specifications

Pinout & Package

MAX6751KA50/V+T is housed in an 8-pin SOT23 package (package code K8+5A, outline 21-0078), optimized for space-constrained automotive PCBs and compatible with standard reflow profiles (260°C peak).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6750KA50/V+T, MAX6751KA50/V+T adds manual-reset capability (pin 1 = MR) at identical dual-supply supervision performance; versus TLV809E50DBZR, it delivers full watchdog scalability, dual-rail monitoring, and automotive temperature support - making it the only option meeting full ECU-level functional safety and feature requirements.

Availability

MAX6751KA50/V+T is available at Aetrix Electronics and suitable for automotive engine control units, ADAS camera modules, infotainment head units, and electric power steering controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6751KA50/V+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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving automotive, industrial, communications, and healthcare markets.

The MAX6746–MAX6753 product line delivers AEC-Q100-qualified μP supervisors with configurable reset/watchdog timing and dual-supply monitoring - designed specifically for functional safety-critical automotive subsystems demanding robustness under voltage transients and extreme temperatures.

FAQ

What is the factory-trimmed reset threshold voltage for MAX6751KA50/V+T?

The MAX6751KA50/V+T has a factory-trimmed VCC reset threshold of 5.000V ±2% (4.900V to 5.100V) across –40°C to +125°C, as confirmed by Table 2 (suffix "50") and Electrical Characteristics. This precise threshold ensures reliable detection of 5V rail brownouts in automotive applications without external calibration. The MAX6751KA50/V+T maintains this accuracy over temperature and supply variations, eliminating need for trimming resistors.

Does MAX6751KA50/V+T support monitoring of two independent supply voltages?

Yes, MAX6751KA50/V+T supports dual-voltage monitoring: it uses its factory-trimmed 5.0V comparator for VCC and its adjustable RESET IN input (1.235V threshold) to monitor a second supply via external resistor divider. When either voltage falls below its respective threshold, MAX6751KA50/V+T asserts RESET. This capability is explicitly documented in the Selector Guide and Detailed Description sections for MAX6751, distinguishing it from single-monitor variants like MAX6746.

How does the watchdog select input (WDS) function on MAX6751KA50/V+T?

On MAX6751KA50/V+T, the WDS pin selects watchdog timeout mode: grounding WDS enables normal mode (tWD = 4.94×10⁶ × CSWT), while connecting WDS to VCC activates extended mode (tWD × 128). A state change on WDS clears the watchdog timer. This behavior is specific to MAX6746–MAX6751 devices and is confirmed in Pin Descriptions and Watchdog Timer sections - differentiating MAX6751KA50/V+T from windowed watchdog variants (MAX6752/MAX6753).

What package type and RoHS status does MAX6751KA50/V+T use?

MAX6751KA50/V+T uses an 8-pin SOT23 package (outline 21-0078, land pattern 90-0176) with package code K8+5A, where the "+" denotes RoHS-compliant lead-free finish. Thermal resistance data (qJA = 196°C/W on four-layer board) and soldering specifications (260°C reflow) are provided in the Absolute Maximum Ratings table. This package meets automotive space and reliability requirements per AEC-Q100.

Is MAX6751KA50/V+T qualified for automotive applications?

Yes, MAX6751KA50/V+T is AEC-Q100 qualified for automotive Grade 0 (–40°C to +125°C), with full validation including temperature cycling, humidity testing, and ESD robustness. Its electrical specifications - including supply current (≤10µA), transient immunity (50µs rejection at 100mV overdrive), and RESET validity down to VCC = 1V - are all tested and guaranteed across this range. This qualification is explicitly stated in the Benefits and Features section and Ordering Information.