Analog Devices Inc./Maxim Integrated MAX6355MSUT+T

Overview

The MAX6355MSUT+T from Maxim Integrated is a triple-voltage microprocessor supervisory circuit with open-drain reset output, monitoring VCC1 (4.38V threshold), VCC2 (2.93V threshold), and a third voltage via RSTIN (1.22V internal comparator). It features 20µA supply current, 100ms min reset timeout, and operates from -40°C to +85°C in a 6-pin SOT23 package for multivoltage embedded systems.

For engineers reviewing the MAX6355MSUT+T datasheet, MAX6355MSUT+T pinout, MAX6355MSUT+T application, or MAX6355MSUT+T equivalent, key selection criteria include dual-supply monitoring with third-voltage support, open-drain reset compatibility with mixed-voltage logic, guaranteed reset validity down to VCC1 = 1V or VCC2 = 1V, and manual-reset debouncing without external components.

Technical Context

The MAX6355MSUT+T implements a dual-supply monitoring architecture where reset is asserted if either VCC1 drops below 4.38V or VCC2 falls below 2.93V, with reset output remaining valid as long as at least one supply exceeds +1.0V. Its RSTIN input provides adjustable third-voltage monitoring using an internal 1.22V comparator and external resistive divider.

This device uses BiCMOS process technology and includes a debounced TTL/CMOS-compatible manual-reset input (MR) with 1µs minimum pulse width and 100ns glitch rejection. Unlike MAX6358–MAX6360 variants, it does not integrate a watchdog timer.

Key Specifications

Pinout & Package

Package: 6-pin SOT23 (U6-1), RoHS-compliant lead(Pb)-free, footprint per land pattern 90-0175.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6356MSUT+T, the MAX6355MSUT+T offers open-drain flexibility for multi-drop reset networks, while TPS3808G33DBVR trades third-voltage monitoring for lower power and simpler dual-rail supervision - neither is pin-compatible, requiring PCB layout changes.

Availability

MAX6355MSUT+T is available at Aetrix Electronics and suitable for computers, portable/battery-powered equipment, intelligent instruments, and multivoltage systems requiring stable component supply, long-term industrial lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6355MSUT+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, communications, and computing applications.

The MAX6351–MAX6360 family delivers highly integrated microprocessor supervisors targeting multivoltage embedded systems where reliability, low power, and minimal external components are essential.

FAQ

What is the function of the RSTIN pin on the MAX6355MSUT+T?

The RSTIN pin on the MAX6355MSUT+T is a dedicated third-voltage monitor input with a fixed 1.22V internal comparator threshold. It allows supervision of a voltage beyond the two primary supplies (VCC1 and VCC2) by connecting an external resistive divider. The input must be referenced to VCC1 and cannot exceed VCC1 in voltage. This feature enables precise monitoring of core voltages, reference rails, or other critical analog supplies in complex multivoltage systems using the MAX6355MSUT+T.

Does the MAX6355MSUT+T include a watchdog timer?

No, the MAX6355MSUT+T does not include a watchdog timer. Watchdog functionality is exclusive to the MAX6358, MAX6359, and MAX6360 variants within the same family. The MAX6355MSUT+T is specifically designed as a triple-voltage supervisor with manual reset and RSTIN-based third-voltage monitoring, but no WDI input or timeout circuitry. Engineers requiring watchdog capability must select MAX6358MSUT+T, MAX6359MSUT+T, or MAX6360MSUT+T instead of the MAX6355MSUT+T.

What are the exact voltage thresholds monitored by the MAX6355MSUT+T?

The MAX6355MSUT+T monitors VCC1 at a factory-set threshold of 4.38V (±0.13V over -40°C to +85°C) and VCC2 at 2.93V (±0.08V over the same temperature range). These values correspond to the "MS" suffix in the part number. Its RSTIN pin provides a third monitoring point with a fixed internal comparator threshold of 1.22V (±0.03V), enabling supervision of additional rails via external resistor dividers. All thresholds are precision-trimmed and fully guaranteed across the industrial temperature range for the MAX6355MSUT+T.

Is the reset output of the MAX6355MSUT+T push-pull or open-drain?

The reset output (RST) of the MAX6355MSUT+T is active-low open-drain. This configuration requires an external pull-up resistor to the appropriate logic rail and supports wired-OR connections with other reset sources. It differs from the push-pull outputs found in MAX6356MSUT+T (VCC1-referenced) and MAX6357MSUT+T (VCC2-referenced). The open-drain structure of the MAX6355MSUT+T enables flexible interfacing across mixed-voltage domains and simplifies integration into systems with multiple reset generators.

What is the minimum operating voltage for valid reset assertion on the MAX6355MSUT+T?

The MAX6355MSUT+T guarantees valid reset assertion as long as either VCC1 or VCC2 remains above +1.0V. This specification ensures reliable brownout detection and reset hold-down even during severe supply droop - a critical feature for fault-tolerant embedded systems. The device continues to monitor both supplies and assert RST until both VCC1 falls below 1.0V and VCC2 falls below 1.0V. This behavior is explicitly guaranteed across the full -40°C to +85°C operating range for the MAX6355MSUT+T.