Analog Devices Inc./Maxim Integrated MAX6357LSUT

Overview

MAX6357LSUT from Maxim Integrated is a dual-voltage microprocessor supervisory IC with triple-monitor capability (VCC1, VCC2, and RSTIN), featuring an active-low push-pull reset output referenced to VCC2, factory-set 4.63V/2.93V thresholds, 20µA supply current, and guaranteed RESET validity down to VCC1 or VCC2 ≥ 1.0V. It is used in multivoltage embedded systems requiring reliable power-on reset and third-voltage monitoring for FPGA I/O banks or analog subsystems.

For engineers reviewing the MAX6357LSUT datasheet, MAX6357LSUT pinout, MAX6357LSUT application, or MAX6357LSUT equivalent, key selection criteria include its VCC2-referenced RST output, 1.22V adjustable RSTIN threshold, SOT23-6 package compatibility, and support for systems where primary reset must track the secondary supply rail.

Technical Context

The MAX6357LSUT integrates two independent voltage comparators for VCC1 and VCC2 monitoring plus a dedicated 1.22V precision reference for external voltage monitoring via RSTIN. Its reset generator asserts RST low whenever either VCC1 drops below 4.63V or VCC2 falls below 2.93V - or when RSTIN falls below 1.22V - with hysteresis and glitch filtering applied to all inputs.

It operates across -40°C to +85°C with full electrical specifications guaranteed, delivers 100ms minimum reset pulse width, and maintains valid reset assertion as long as at least one supply remains ≥ 1.0V. The RST output is push-pull and referenced to VCC2, enabling direct interfacing with VCC2-domain logic without level shifting.

Key Specifications

Pinout & Package

MAX6357LSUT is housed in a 6-pin SOT23-6 package with 1.6mm × 2.9mm footprint and 0.95mm height, suitable for space-constrained PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6357LTUT, the MAX6357LSUT provides higher VCC1 threshold (4.63V vs. 4.38V) for tighter 5V rail margin control; compared with TPS3808G33DBVR, it eliminates need for discrete comparators and supports true triple-voltage supervision in one chip.

Availability

MAX6357LSUT is available at Aetrix Electronics and suitable for computers, intelligent instruments, controllers, multivoltage systems, and portable/battery-powered equipment requiring stable component supply, long-term lifecycle assurance, and industrial-temperature operation.

Supply support for MAX6357LSUT 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, mixed-signal, and power management ICs for industrial, computing, and communications applications.

The MAX6351–MAX6360 family delivers highly integrated, low-power supervisory solutions for multivoltage embedded systems - specifically targeting reliability-critical applications where simultaneous monitoring of multiple rails and third-voltage validation are required.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6357LSUT?

The MAX6357LSUT has a factory-trimmed VCC1 threshold of 4.63V ±2.5% and a VCC2 threshold of 2.93V ±2.5%, as defined by the "LS" suffix per Maxim's Voltage Threshold Levels table. These values are fully guaranteed over -40°C to +85°C and enable precise supervision of standard 5V and 3.3V rails. The MAX6357LSUT uses these thresholds to assert reset whenever either supply drops below its respective trip point.

How does the RSTIN pin function on the MAX6357LSUT, and what voltage can it monitor?

The RSTIN pin on the MAX6357LSUT is a precision 1.22V ±0.03V comparator input that enables monitoring of a third voltage rail. By connecting an external resistive divider between the target voltage and GND, with the midpoint fed to RSTIN, the MAX6357LSUT can supervise voltages such as 1.8V, 2.5V, or 3.3V. The MAX6357LSUT requires RSTIN to remain ≤ VCC1, and its internal reference ensures accurate detection without external components.

Is the reset output of the MAX6357LSUT push-pull or open-drain, and which supply does it reference?

Yes, the MAX6357LSUT features an active-low push-pull reset output (RST) that is explicitly referenced to VCC2, not VCC1. This means the high-state voltage equals VCC2, and the low-state voltage is ≤0.3V at 50µA sink current. This architecture allows direct connection to VCC2-domain logic without level shifters. The MAX6357LSUT does not offer open-drain configuration - only push-pull with VCC2 referencing.

Does the MAX6357LSUT include a watchdog timer function?

No, the MAX6357LSUT does not include a watchdog timer. Watchdog functionality is exclusive to the MAX6358/MAX6359/MAX6360 variants in the same family. The MAX6357LSUT belongs to the MAX6355/MAX6356/MAX6357 subgroup, which adds the RSTIN third-voltage monitor but omits WDI. Therefore, the MAX6357LSUT provides dual-supply supervision plus adjustable third-rail monitoring - no watchdog timing or WDI pin.

What package type and pin count does the MAX6357LSUT use, and is it RoHS-compliant?

The MAX6357LSUT is supplied in a 6-pin SOT23-6 package (1.6mm × 2.9mm body, 0.95mm max height) with lead-free (RoHS-compliant) construction. The "-T" suffix indicates tape-and-reel packaging; lead-free versions are ordered with "+T". This compact, surface-mount package supports automated assembly and meets IPC/JEDEC standards for reflow soldering. All MAX6357LSUT units shipped by Aetrix Electronics are RoHS-compliant and traceable to Maxim's qualified manufacturing lots.