Analog Devices Inc./Maxim Integrated MAX6358TZUT

Overview

The MAX6358TZUT from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with open-drain active-low reset output, 3.08V VCC1 threshold, 2.32V VCC2 threshold, watchdog timer (46.4s startup / 2.9s normal timeout), and guaranteed RESET validity down to VCC1 = 1V or VCC2 = 1V - used in multivoltage embedded systems requiring reliable power-on reset and processor activity monitoring.

For engineers reviewing the MAX6358TZUT datasheet, MAX6358TZUT pinout, MAX6358TZUT application, or MAX6358TZUT equivalent, key selection considerations include its dual-supply monitoring capability, open-drain RST output compatible with mixed-voltage logic, watchdog timing architecture, and operation across –40°C to +85°C industrial temperature range.

Technical Context

The MAX6358TZUT implements a dual-threshold voltage monitor with independent VCC1 and VCC2 inputs, asserting reset when either supply drops below its factory-set threshold (3.08V and 2.32V respectively). Its reset generator guarantees valid output as long as at least one supply remains ≥1.0V, enabling robust brownout detection in asymmetric power domains.

It integrates a dual-mode watchdog timer: a 46.4s startup timeout allows full system initialization after power-up or manual reset, followed by a 2.9s normal timeout that requires periodic WDI transitions to prevent reset - supporting both boot-time flexibility and runtime fault detection in microprocessor-based systems.

Key Specifications

Pinout & Package

MAX6358TZUT is housed in a 6-pin SOT23 package (U6-1 outline), surface-mount, RoHS-compliant, with 0.95mm pitch and 2.9mm × 1.6mm footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-voltage supervisory applications.

Compared with MAX6358TUT, the MAX6358TZUT offers identical supervision performance with lead-free compliance; versus TPS3808G33DBVR, it adds critical dual-voltage monitoring and watchdog capability essential for complex multirail microprocessor systems.

Availability

MAX6358TZUT is available at Aetrix Electronics and suitable for computers, controllers, and portable/battery-powered equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6358TZUT 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 industrial, computing, and communications applications.

The MAX6351–MAX6360 family delivers dual- and triple-voltage μP supervisors optimized for reliability-critical embedded systems needing accurate, low-power, multi-rail power monitoring and watchdog protection.

FAQ

What is the function of Pin 5 (WDI) on the MAX6358TZUT?

Pin 5 is the Watchdog Input (WDI) of the MAX6358TZUT. It accepts periodic rising or falling edges to reset the internal watchdog timer. If no transition occurs within 2.9s during normal operation-or within 46.4s during startup-the MAX6358TZUT asserts its open-drain RST output. Leaving WDI unconnected disables the watchdog function entirely.

Does the MAX6358TZUT support operation with VCC1 and VCC2 below 2.0V?

Yes, the MAX6358TZUT operates with VCC1 and VCC2 as low as +1.2V over the full –40°C to +85°C range, and its RESET output remains valid down to VCC1 = 1V or VCC2 = 1V. This enables use in low-voltage systems such as those powered by single-cell Li-ion batteries with buck regulators delivering 3.08V and 2.32V rails.

What is the reset output type of the MAX6358TZUT, and how should it be interfaced?

The MAX6358TZUT features an active-low open-drain RST output (Pin 1). It requires an external pull-up resistor to the target logic rail (e.g., 10kΩ to +3.3V). This configuration supports level translation, wired-OR reset buses, and compatibility with microprocessors having bidirectional reset pins when combined with a series resistor (e.g., 4.7kΩ).

How does the MAX6358TZUT handle simultaneous undervoltage on both VCC1 and VCC2?

When either VCC1 drops below 3.08V or VCC2 drops below 2.32V, the MAX6358TZUT immediately asserts RST. If both supplies fall simultaneously, RST is asserted based on the first threshold violation. The device guarantees RST remains valid as long as at least one supply stays ≥1.0V - ensuring deterministic reset behavior even during correlated brownouts.

Is the MAX6358TZUT pin-compatible with other devices in the MAX6351–MAX6360 family?

Yes, the MAX6358TZUT shares the same 6-pin SOT23 (U6-1) package and pinout as all 6-pin variants in the MAX6351–MAX6360 family, including MAX6355UT, MAX6356UT, MAX6359UT, and MAX6360UT. However, internal functionality differs: MAX6358TZUT provides open-drain RST and WDI, whereas MAX6359UT offers push-pull RST referenced to VCC1 and WDI, and MAX6356UT provides push-pull RST and RSTIN for third-voltage monitoring.