Analog Devices Inc./Maxim Integrated MAX6753KA42/V+T

Overview

MAX6753KA42/V+T from Analog Devices is a window watchdog supervisory IC for automotive-grade microprocessor monitoring, featuring factory-trimmed 4.2V VCC reset threshold (±2%), capacitor-adjustable reset timeout (5.7–9.5ms), and dual-window watchdog with fast/slow fault detection (tWD1 = 11.4–152ms, tWD2 = 729–1214ms). It operates from 1.2V to 5.5V supply and supports manual reset input and open-drain active-low RESET output in an AEC-Q100-qualified 8-pin SOT23 package.

For engineers reviewing the MAX6753KA42/V+T datasheet, MAX6753KA42/V+T pinout, MAX6753KA42/V+T application, or MAX6753KA42/V+T equivalent, this page delivers verified functional identity, automotive temperature range (-40°C to +125°C), window watchdog timing equations, reset threshold tolerance, and validated alternative part comparisons - all grounded in official Analog Devices documentation.

Technical Context

The MAX6753KA42/V+T implements a min/max (windowed) watchdog architecture that asserts RESET when WDI falling edges occur either faster than tWD1 (fast fault) or slower than tWD2 (slow fault), with tWD1 selectable via SET0/SET1 pin strapping (8×, 16×, or 64× ratio relative to tWD2). Its VCC monitor uses a ±2% factory-trimmed 4.2V threshold, and RESET remains asserted for a capacitor-programmable timeout (tRP = 4.94 × 10⁶ × CSRT).

Unlike MAX6746–MAX6751 variants, MAX6753 lacks WDS and MR pins but includes SET0/SET1 for watchdog window configuration and supports only open-drain RESET output. It does not support extended-mode watchdog or manual reset - functions reserved for earlier family members - and requires external resistor-divider only if monitoring secondary voltages beyond VCC.

Key Specifications

Pinout & Package

MAX6753KA42/V+T is housed in an 8-pin SOT23 package (Outline 21-0078, Land Pattern 90-0176), RoHS-compliant, with thermal resistance θJA = 196°C/W on four-layer board.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6753KA42/V+T, MAX6752KA42/V+T offers identical supervision timing but eliminates external pullup dependency via push-pull output, while TLV809E42DBZR reduces cost and footprint at the expense of watchdog capability and design flexibility.

Availability

MAX6753KA42/V+T is available at Aetrix Electronics and suitable for automotive ECU, medical infusion pumps, industrial PLCs, and smart energy meters requiring stable component supply with AEC-Q100 assurance and long-term production continuity.

Supply support for MAX6753KA42/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 precision instrumentation, industrial automation, and automotive markets since 1965.

The MAX6746–MAX6753 family was designed specifically for robust, low-power microprocessor supervision in harsh environments - emphasizing reset accuracy, transient immunity, and configurable watchdog architectures for safety-critical embedded systems.

FAQ

What is the exact reset threshold voltage of MAX6753KA42/V+T and how is it trimmed?

The MAX6753KA42/V+T features a factory-trimmed VCC reset threshold of 4.200V with ±2% tolerance over -40°C to +125°C. This value is laser-trimmed during production and corresponds to suffix "42" in the part number per Table 2 of the datasheet. No external resistor divider is required when monitoring a nominal 4.2V supply rail, as the threshold is internally fixed and temperature-compensated.

Does MAX6753KA42/V+T support manual reset (MR) functionality?

No, MAX6753KA42/V+T does not include a manual reset (MR) input. Pin 1 is assigned to SET0, and pin 2 to SET1 - confirming its role as a window watchdog variant without MR capability. Manual reset is only present on MAX6746/MAX6747 (pin 1 = MR) and MAX6748–MAX6751 (via RESET IN). For designs requiring MR, consider MAX6751KA42/V+T instead.

How do I calculate the capacitor values for reset and watchdog timeouts on MAX6753KA42/V+T?

For reset timeout: use CSRT = tRP / 4.94 × 10⁶, where tRP is in seconds (e.g., 8ms → CSRT ≈ 1620pF). For slow watchdog period tWD2: use CSWT = tWD2 / 0.65 × 10⁹ (e.g., 975ms → CSWT ≈ 1500pF). Fast watchdog period tWD1 is derived from tWD2 using SET0/SET1 ratio (8×, 16×, or 64×). Both capacitors must be low-leakage ceramic types.

What is the function of SET0 and SET1 pins on MAX6753KA42/V+T?

SET0 and SET1 are logic inputs that configure the tWD1/tWD2 window ratio for the min/max watchdog. Per Table 1: SET0=LOW/SET1=LOW selects 8× ratio; LOW/HIGH selects 16×; HIGH/HIGH selects 64×; HIGH/LOW disables the watchdog. These pins are strapped at power-up and determine the fast-fault detection boundary relative to the slow-fault period set by CSWT.

Is MAX6753KA42/V+T compatible with 1.8V or 2.5V supply rails?

Yes, MAX6753KA42/V+T operates from VCC = 1.2V to 5.5V and guarantees RESET validity for VCC ≥ 1V. However, its 4.2V factory-trimmed threshold is intended for monitoring higher-voltage rails. To supervise 1.8V or 2.5V supplies, use the adjustable RESET IN input (not available on MAX6753 - see MAX6748–MAX6751) or select a different suffix (e.g., MAX6753KA25/V+T for 2.5V).