Analog Devices Inc./Maxim Integrated MAX6752KA46+T

Overview

MAX6752KA46+T from Analog Devices is a window watchdog supervisory IC for microprocessor systems, featuring factory-trimmed 4.625V ±2% VCC reset threshold, capacitor-adjustable reset timeout (5.7–9.5ms), slow/fast watchdog periods (729–1214ms and 11.4–91.1ms), manual-reset input, and push-pull active-low RESET output. It operates across -40°C to +125°C and supports automotive-grade reliability.

For engineers reviewing the MAX6752KA46+T datasheet, MAX6752KA46+T pinout, MAX6752KA46+T application, or MAX6752KA46+T equivalent, this device delivers precise dual-window watchdog timing, AEC-Q100 qualification, low 3.7µA supply current, and robust power-supply transient immunity - critical for safety-critical embedded control and automotive subsystems.

Technical Context

The MAX6752KA46+T implements a min/max (windowed) watchdog architecture that detects both early and late transitions on WDI: fast faults occur when falling edges are shorter than tWD1 (11.4–91.1ms), slow faults when intervals exceed tWD2 (729–1214ms). Its reset comparator uses a precision 4.625V ±2% internal reference with 0.8% hysteresis, and reset assertion is guaranteed down to VCC = 1V.

Reset timeout (tRP) and slow watchdog period (tWD2) are set via external capacitors CSRT and CSWT using linear scaling formulas: tRP = 4.94×10⁶ × CSRT and tWD2 = 0.65×10⁹ × CSWT. Fast watchdog period tWD1 is selected by strapping SET0/SET1 pins (8×, 16×, or 64× ratio relative to tWD2), enabling fine-grained fault window tuning without software intervention.

Key Specifications

Pinout & Package

MAX6752KA46+T is housed in an 8-pin SOT23 package (outline 21-0078), measuring 2.9mm × 1.6mm × 1.1mm, with gull-wing leads optimized for high-density PCB layouts and automotive reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6752KA46+T, MAX6753KA46+T offers open-drain flexibility at the cost of added external pull-up, while TPS3808G33DBVR reduces cost and power but sacrifices windowed watchdog precision and 5V-system compatibility.

Availability

MAX6752KA46+T is available at Aetrix Electronics and suitable for automotive engine control units, industrial PLC safety monitors, medical infusion pump controllers, and ADAS camera modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6752KA46+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 industrial, automotive, communications, and healthcare markets with precision timing, power management, and sensor solutions.

The MAX6746–MAX6753 family was designed specifically for automotive and industrial microprocessor supervision, delivering AEC-Q100-qualified windowed watchdog functionality, ultra-low quiescent current, and robust transient immunity in miniature SOT23 packages.

FAQ

What is the exact reset threshold voltage for MAX6752KA46+T?

The MAX6752KA46+T features a factory-trimmed VCC reset threshold of 4.625V with ±2% tolerance over -40°C to +125°C. This value is confirmed in the Electrical Characteristics table under "VCC Reset Threshold" and corresponds to suffix "46" in the ordering code per Table 2 of the datasheet. The hysteresis is 0.8% of VCC, ensuring clean release without chatter during voltage recovery.

How does the windowed watchdog in MAX6752KA46+T differ from standard watchdog timers?

The MAX6752KA46+T implements a true min/max (windowed) watchdog: it asserts RESET if WDI falling edges occur either too soon (< tWD1) or too late (> tWD2), unlike standard watchdogs that only detect timeouts. This dual-bound detection prevents both runaway loops and processor hangs, making MAX6752KA46+T suitable for safety-critical real-time applications where timing predictability is mandatory.

Can MAX6752KA46+T monitor two different supply voltages simultaneously?

No - MAX6752KA46+T monitors only the VCC supply using its internal 4.625V threshold. Unlike MAX6750/MAX6751 variants, it does not include the adjustable RESET IN input required for dual-voltage monitoring. To supervise a second rail, an external resistor divider feeding a separate supervisor or ADC channel is required; MAX6752KA46+T itself supports single-rail 5V system supervision only.

What capacitor values are recommended for setting tRP = 8ms and tWD2 = 1000ms on MAX6752KA46+T?

Using the formulas tRP = 4.94×10⁶ × CSRT and tWD2 = 0.65×10⁹ × CSWT: for tRP = 8ms, CSRT ≈ 1620pF (standard 1500pF yields 7.59ms); for tWD2 = 1000ms, CSWT ≈ 1539pF (standard 1500pF yields 975ms). Use low-leakage ceramic capacitors (X7R/C0G) with ≤10nA leakage to maintain timing accuracy across temperature and voltage.

Is MAX6752KA46+T compatible with 3.3V microcontrollers?

Yes - MAX6752KA46+T accepts VCC from 1.2V to 5.5V and its push-pull RESET output drives low to <0.4V at VCC ≥ 4.5V with 3.2mA sink capability, fully compatible with 3.3V logic thresholds. The 4.625V reset threshold remains valid regardless of µP I/O voltage, as RESET assertion depends solely on VCC crossing that threshold, not µP voltage levels.