Analog Devices Inc./Maxim Integrated MAX6358MSUT+T

Overview

MAX6358MSUT+T from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with open-drain active-low reset output, 4.38V VCC1 threshold, 2.93V VCC2 threshold, 46.4s watchdog startup timeout, and 2.9s normal watchdog timeout. It monitors two independent supply rails in multivoltage systems and asserts reset if either supply drops below its preset threshold while maintaining valid RESET down to VCC1 ≥ 1.0V or VCC2 ≥ 1.0V - used in portable battery-powered equipment requiring reliable power-on and fault detection.

For engineers reviewing the MAX6358MSUT+T datasheet, MAX6358MSUT+T pinout, MAX6358MSUT+T application, or MAX6358MSUT+T equivalent, key selection criteria include dual-supply monitoring capability, watchdog timer timing parameters (46.4s/2.9s), open-drain RST output compatibility with mixed-voltage logic interfaces, and guaranteed operation over -40°C to +85°C.

Technical Context

The MAX6358MSUT+T implements a dual-threshold voltage monitor with independent VCC1 and VCC2 inputs, each compared against factory-trimmed precision thresholds (4.38V and 2.93V respectively). Its reset generator asserts an open-drain RST signal when either supply falls below its trip point, with hysteresis of VTH/500 and guaranteed validity down to 1.0V on either rail.

It integrates a dual-mode watchdog timer: a 46.4s startup timeout (min 25.6s, max 72.0s) enables safe system boot initialization, followed by a 2.9s normal timeout (min 1.6s, max 4.5s) for runtime processor activity monitoring. WDI input accepts TTL/CMOS-compatible edges and clears the timer on any rising or falling transition.

Key Specifications

Pinout & Package

MAX6358MSUT+T is housed in a lead(Pb)-free 6-pin SOT23 package (U6-1 outline, land pattern 90-0175), with 1.6mm × 2.9mm footprint and 0.95mm height - compatible with standard high-density PCB assembly processes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6358MTUT+T, the MAX6358MSUT+T provides higher VCC1 threshold (4.38V vs. 3.08V) for robust supervision of +5V rails, while retaining identical watchdog behavior and pin compatibility. Against TPS3808G33DBVR, it delivers integrated dual-rail monitoring and hardware watchdog - eliminating design complexity and board space for multivoltage systems.

Availability

MAX6358MSUT+T is available at Aetrix Electronics and suitable for portable/battery-powered equipment, intelligent instruments, and multivoltage systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6358MSUT+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 and mixed-signal ICs for industrial, computing, communications, and consumer applications - emphasizing reliability, low power, and integration.

The MAX6351–MAX6360 family delivers dual- and triple-voltage microprocessor supervisors with integrated watchdog timers, targeting systems requiring robust power sequencing, brownout protection, and runtime fault detection without external components.

FAQ

What is the function of the WDI pin on the MAX6358MSUT+T?

The WDI (Watchdog Input) pin on the MAX6358MSUT+T resets the internal watchdog timer on every rising or falling edge. If no edge occurs within 2.9s (normal mode) or 46.4s (startup mode), the device asserts the RST output. Leaving WDI unconnected disables the watchdog function entirely, and the MAX6358MSUT+T operates as a dual-voltage supervisor only.

Does the MAX6358MSUT+T support operation when one supply rail drops to 1.0V?

Yes - the MAX6358MSUT+T guarantees valid RST output as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, per Absolute Maximum Ratings and Electrical Characteristics. This ensures reliable reset assertion during brownout conditions where one rail collapses but the other remains marginally active, a key feature for fail-safe system behavior.

What is the reset pulse width specification for the MAX6358MSUT+T?

The MAX6358MSUT+T provides a minimum reset pulse width of 100ms, with typical values ranging from 100ms to 280ms depending on supply conditions. This duration exceeds the reset hold-time requirements of most microprocessors and FPGAs, ensuring proper initialization before release from reset.

Can the MAX6358MSUT+T monitor three voltage rails?

No - the MAX6358MSUT+T monitors exactly two voltage rails (VCC1 and VCC2). For triple-voltage supervision, consider the MAX6355/MAX6356/MAX6357 variants, which add an RSTIN pin for monitoring a third voltage via an external resistive divider. The MAX6358MSUT+T lacks RSTIN and does not support third-rail monitoring.

Is the MAX6358MSUT+T pin-compatible with other devices in the MAX6351–MAX6360 family?

Yes - all 6-pin SOT23 variants in the MAX6351–MAX6360 family, including MAX6358MSUT+T, share identical pinout (RST, GND, MR, VCC2, WDI, VCC1). However, functional differences exist: MAX6358MSUT+T has open-drain RST and integrated watchdog, whereas MAX6351 offers dual push-pull RST outputs and no watchdog. Pin compatibility enables layout reuse but requires firmware and schematic validation.