Analog Devices Inc./Maxim Integrated MAX6351LSUT+T

Overview

MAX6351LSUT+T from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with two active-low push-pull reset outputs-one referenced to VCC1 (4.63V threshold), the other to VCC2 (2.93V threshold)-operating over -40°C to +85°C, consuming 20µA supply current, and guaranteeing RESET validity down to VCC1 ≥ 1.0V or VCC2 ≥ 1.0V. It is used in multivoltage embedded systems requiring coordinated reset assertion across independent power rails.

For engineers reviewing the MAX6351LSUT+T datasheet, MAX6351LSUT+T pinout, MAX6351LSUT+T application, or MAX6351LSUT+T equivalent, key selection criteria include dual-supply threshold accuracy (±0.09V at +25°C), 100ms minimum reset pulse width, guaranteed operation with either supply ≥1.0V, and SOT23-6 package compatibility for space-constrained PCB layouts.

Technical Context

The MAX6351LSUT+T implements independent precision voltage comparators for VCC1 and VCC2, each with factory-trimmed thresholds (4.63V and 2.93V respectively) and 20ppm/°C tempco. Reset assertion occurs if either supply drops below its trip point, and both RST1 and RST2 remain valid as long as at least one supply exceeds +1.0V.

It features a debounced TTL/CMOS-compatible manual-reset input (MR), no watchdog or third-voltage monitor functionality (distinguishing it from MAX6358/MAX6355 variants), and operates with VCC1/VCC2 ranging from +1.2V to +5.5V across the full temperature range.

Key Specifications

Pinout & Package

MAX6351LSUT+T is housed in a 6-pin SOT23 package (U6-1 outline, land pattern 90-0175), with exposed pad not electrically connected. The device uses BiCMOS process technology and supports lead(Pb)-free soldering per RoHS.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6353LSUT+T and TPS3808G33DBVR, the MAX6351LSUT+T uniquely delivers true independent dual-rail supervision with two dedicated push-pull reset outputs-enabling deterministic, rail-specific reset control without external components or timing compromises.

Availability

MAX6351LSUT+T is available at Aetrix Electronics and suitable for industrial PLC controllers, portable medical diagnostics, automotive infotainment head units, and multivoltage sensor nodes requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6351LSUT+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, computing, and consumer applications.

The MAX6351–MAX6360 family was developed specifically for multivoltage microprocessor systems requiring coordinated, rail-specific reset generation without external components or timing uncertainty.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6351LSUT+T?

The MAX6351LSUT+T has a factory-set VCC1 threshold of 4.63V (±0.09V at +25°C) and a VCC2 threshold of 2.93V (±0.05V at +25°C), as defined by the "LS" suffix in the ordering code. These values are guaranteed over the full -40°C to +85°C operating range and reflect precision trimming during wafer test.

Does the MAX6351LSUT+T include a watchdog timer function?

No, the MAX6351LSUT+T does not include a watchdog timer. Watchdog functionality is exclusive to the MAX6358/MAX6359/MAX6360 variants in the same family. The MAX6351LSUT+T provides only dual-voltage monitoring and dual active-low push-pull reset outputs (RST1 and RST2).

Can the MAX6351LSUT+T operate with supply voltages below 1.2V?

The MAX6351LSUT+T guarantees RESET output validity down to VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, but its specified operating range begins at +1.2V. Below 1.2V, functionality is not characterized or guaranteed-designs requiring sub-1.2V operation should verify behavior empirically and consult the Absolute Maximum Ratings table.

What is the minimum reset pulse width guaranteed by the MAX6351LSUT+T?

The MAX6351LSUT+T guarantees a minimum reset pulse width of 100ms after power-up or manual reset assertion. This value is fully characterized over temperature and supply voltage and meets standard microprocessor reset timing requirements without external timing components.

Is the MAX6351LSUT+T pin-compatible with other devices in the MAX6351–MAX6360 family?

The MAX6351LSUT+T uses the 6-pin SOT23 package and shares identical pinout with all other 6-pin variants (e.g., MAX6355, MAX6358, MAX6359), including RST1, GND, MR, VCC2, RST2, and VCC1 assignments. However, internal functionality differs-e.g., MAX6355 adds RSTIN, MAX6358 adds WDI-so electrical compatibility requires verification per application.