Analog Devices Inc./Maxim Integrated MAX6355UWUT+T

Overview

MAX6355UWUT+T from Maxim Integrated is a triple-voltage microprocessor supervisory circuit with open-drain reset output, monitoring VCC1 (2.78V threshold), VCC2 (1.67V threshold), and a third voltage via RSTIN (1.22V internal comparator). It features 20µA supply current, 100ms min reset timeout, and operates over -40°C to +85°C in a 6-pin SOT23 package for multivoltage embedded systems.

For engineers reviewing the MAX6355UWUT+T datasheet, MAX6355UWUT+T pinout, MAX6355UWUT+T application, or MAX6355UWUT+T equivalent, key selection factors include its dual-supply monitoring capability, RSTIN-based third-voltage supervision, open-drain reset architecture, and guaranteed RESET validity down to VCC1 = 1V or VCC2 = 1V.

Technical Context

The MAX6355UWUT+T implements a precision dual-threshold voltage monitor with factory-set VTH1 = 2.78V (±0.08V over temperature) and VTH2 = 1.67V (±0.09V), plus an adjustable third-voltage input (RSTIN) with 1.22V ±0.03V internal reference. Its reset generator asserts active-low open-drain RST when any monitored supply drops below its threshold or when MR is asserted.

Unlike variants with watchdog or push-pull outputs, MAX6355UWUT+T omits WDI and provides no watchdog timer; it includes debounced manual-reset input (MR) with 1µs minimum pulse width and 100ns glitch rejection, and guarantees functional operation as long as either VCC1 or VCC2 remains ≥1.0V.

Key Specifications

Pinout & Package

MAX6355UWUT+T is housed in a RoHS-compliant 6-pin SOT23 package (U6-1 outline, land pattern 90-0175), with 0.95mm pitch, 2.9mm × 1.6mm footprint, and 1.1mm max height - suitable for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6355UWUT+T, MAX6356UWUT+T offers push-pull drive but loses wired-OR flexibility, while TPS3808G33DBVR reduces integration by omitting dedicated RSTIN-requiring external resistors to emulate third-rail monitoring.

Availability

MAX6355UWUT+T is available at Aetrix Electronics and suitable for industrial PLC controllers, battery-powered IoT sensors, multivoltage medical devices, and automotive body control modules requiring stable component supply across extended temperature ranges.

Supply support for MAX6355UWUT+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, and communications applications, with emphasis on reliability and low-power operation.

The MAX6351–MAX6360 family delivers multivoltage µP supervision for systems where simultaneous monitoring of two or three independent power rails is essential to prevent erratic behavior during power sequencing or brownout events.

FAQ

What is the function of the RSTIN pin on the MAX6355UWUT+T?

The RSTIN pin on the MAX6355UWUT+T is an undervoltage-comparator input with a precise 1.22V ±0.03V internal reference. It allows supervision of a third voltage rail using an external resistive divider. When the divided voltage falls below the threshold, the device asserts the open-drain RST output. RSTIN must be powered from VCC1 and cannot exceed VCC1 in voltage.

Does the MAX6355UWUT+T include a watchdog timer?

No, the MAX6355UWUT+T does not include a watchdog timer. Watchdog functionality is exclusive to the MAX6358/MAX6359/MAX6360 variants in the same family. The MAX6355UWUT+T provides triple-voltage supervision (VCC1, VCC2, RSTIN) and manual reset only - confirmed by its pinout (Pin 5 = RSTIN, not WDI) and absence of watchdog timing specifications in its electrical characteristics table.

What are the exact voltage thresholds for MAX6355UWUT+T?

The MAX6355UWUT+T has VCC1 threshold = 2.78V (±0.08V over –40°C to +85°C) and VCC2 threshold = 1.67V (±0.09V over temperature). These values are defined by the "UW" suffix per the Voltage Threshold Levels table. The RSTIN comparator threshold is fixed at 1.22V ±0.03V, independent of supply voltages.

Can MAX6355UWUT+T operate with VCC1 or VCC2 below 1.2V?

Yes - the MAX6355UWUT+T guarantees RESET output validity as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, even though the recommended operating range starts at 1.2V. This feature ensures robust reset assertion during deep brownout conditions, enabling controlled system shutdown before logic states become undefined.

What package type and RoHS status does MAX6355UWUT+T use?

The MAX6355UWUT+T uses a 6-pin SOT23 package (outline U6-1, land pattern 90-0175) and is RoHS-compliant, indicated by the "+T" suffix. The "+" denotes lead(Pb)-free packaging per Maxim's ordering convention, and the device meets JEDEC standard SOT23-6 mechanical dimensions with 0.95mm pin pitch.