Analog Devices Inc./Maxim Integrated MAX6351TZUT-T

Overview

The MAX6351TZUT-T from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with two active-low push-pull reset outputs-RST1 referenced to VCC1 and RST2 referenced to VCC2-designed for systems monitoring +3.08V and +2.32V supplies. It guarantees valid reset assertion down to VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, features 20µA supply current, 100ms minimum power-on-reset pulse width, and operates across –40°C to +85°C in a 6-pin SOT23 package. It is used in multivoltage embedded controllers requiring precise, low-power supply monitoring.

For engineers reviewing the MAX6351TZUT-T datasheet, MAX6351TZUT-T pinout, MAX6351TZUT-T application, or MAX6351TZUT-T equivalent, this page delivers verified technical context, exact pin functions, real-world use cases, and validated alternative parts for dual-supply reset supervision in industrial and portable electronics.

Technical Context

The MAX6351TZUT-T implements independent voltage comparators for VCC1 and VCC2, each with factory-trimmed thresholds (3.08V ±0.08V and 2.32V ±0.07V respectively), hysteresis of ~0.005V, and tempco ≤20ppm/°C. Its reset generator asserts both RST1 and RST2 simultaneously if either supply drops below its threshold, with guaranteed reset validity as long as at least one supply remains ≥1.0V.

It integrates a debounced TTL/CMOS-compatible manual-reset input (MR) with <1µs glitch rejection and sub-0.1µs MR-to-reset delay. Unlike MAX6358–MAX6360 variants, it lacks watchdog timer functionality, and unlike MAX6355–MAX6357, it does not include a third adjustable reset comparator input (RSTIN).

Key Specifications

Pinout & Package

MAX6351TZUT-T is housed in a 6-pin SOT23 package (package code U6-1, outline 21-0058), with 0.95mm pitch, 2.9mm × 1.6mm body, and exposed pad not connected internally.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6351TZUT-T, MAX6353TZUK-T reduces pin count and cost but sacrifices independent VCC2 supervision and dual reset signaling; TLV809E30DBZR offers lower price and smaller footprint but cannot replace the coordinated dual-rail monitoring and rail-specific push-pull drive essential to MAX6351TZUT-T's system-level reliability role.

Availability

MAX6351TZUT-T is available at Aetrix Electronics and suitable for industrial PLC controllers, portable medical monitors, automotive body control modules, and networked industrial sensors requiring stable component supply with guaranteed long-term sourcing.

Supply support for MAX6351TZUT-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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX6351–MAX6360 family was designed specifically for multivoltage microprocessor systems requiring precision, low-power, and rail-specific reset coordination-targeting embedded controllers, instrumentation, and battery-operated equipment.

FAQ

What is the exact VCC1 and VCC2 threshold voltage for MAX6351TZUT-T?

The MAX6351TZUT-T has a VCC1 threshold of 3.08V (±0.08V over –40°C to +85°C) and a VCC2 threshold of 2.32V (±0.07V over temperature). These values are factory-trimmed and specified in the Voltage Threshold Levels table of the datasheet; the "TZ" suffix directly maps to this 3.08V/2.32V combination. Both thresholds include built-in hysteresis (~0.005V) to prevent chatter near trip points.

Does MAX6351TZUT-T include a watchdog timer function?

No, MAX6351TZUT-T does not include a watchdog timer. Watchdog functionality is exclusive to the MAX6358, MAX6359, and MAX6360 variants in the same family. The MAX6351TZUT-T provides only dual-voltage monitoring with manual reset and two rail-referenced push-pull reset outputs-RST1 (VCC1) and RST2 (VCC2)-with no WDI pin or timeout circuitry.

What is the minimum operating voltage for MAX6351TZUT-T to guarantee valid reset output?

MAX6351TZUT-T guarantees valid reset output as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V. This means the device continues asserting RST1 and RST2 correctly-even during deep brownout-provided at least one monitored supply remains above 1.0V. This specification is fully tested and guaranteed across the –40°C to +85°C temperature range.

Can MAX6351TZUT-T be used in a system with only one supply voltage?

Yes, MAX6351TZUT-T can supervise a single supply by connecting both VCC1 and VCC2 to the same rail (e.g., +3.08V), while leaving the unused reset output unconnected. However, doing so forfeits the dual-rail coordination benefit. For single-rail applications, lower-cost alternatives like MAX6353TZUK-T (5-pin, VCC1-only reset) may be more appropriate without sacrificing performance.

Is MAX6351TZUT-T RoHS-compliant and lead-free?

Yes, MAX6351TZUT-T is RoHS-compliant and lead(Pb)-free. The "-T" suffix denotes tape-and-reel packaging with lead-free finish; Maxim specifies that lead-free versions are ordered by replacing "-T" with "+T", confirming the base -T variant meets JEDEC J-STD-020 and RoHS Directive 2011/65/EU requirements. The SOT23 package uses matte tin plating over copper leadframe.