Analog Devices Inc./Maxim Integrated MAX6343LUT+

Overview

MAX6343LUT+ from Maxim Integrated is a precision microprocessor supervisory circuit with active-low open-drain reset output, factory-trimmed 4.63V VCC reset threshold, +1.25V power-fail comparator input, and guaranteed RESET assertion down to VCC = +1V. It monitors supply integrity in battery-powered systems and provides early warning of power failure via PFO. Designed for portable telecom and multivoltage embedded control applications.

For engineers reviewing the MAX6343LUT+ datasheet, MAX6343LUT+ pinout, MAX6343LUT+ application, or MAX6343LUT+ equivalent, key selection considerations include its open-drain reset configuration (requiring external pull-up), 100ms minimum reset timeout, -40°C to +125°C operating range, and SOT23-6 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6343LUT+ integrates a precision voltage detector for VCC monitoring and a separate +1.25V reference-based comparator for PFI input, enabling independent power-fail detection. Its reset generator asserts an active-low open-drain signal for ≥100ms after VCC rises above 4.63V or MR transitions high.

It features debounced CMOS-compatible MR input with 1µs glitch rejection, 0.1µs MR-to-reset delay, and guaranteed VOL ≤ 0.4V at ISINK = 100µA. The device operates across full industrial temperature range (-40°C to +125°C) with supply current as low as 1.2µA at VCC = 1V.

Key Specifications

Pinout & Package

MAX6343LUT+ is housed in a RoHS-compliant 6-pin SOT23-6 package (2.9mm × 1.6mm × 1.1mm), optimized for high-density PCB layouts in portable and telecom equipment.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX6342LUT+, the MAX6343LUT+ trades push-pull drive for open-drain flexibility and retains full PFI/PFO functionality; versus TLV803EC26DBZR, it adds critical dual-monitoring capability and wider voltage/temperature coverage at higher BOM cost.

Availability

MAX6343LUT+ is available at Aetrix Electronics and suitable for portable computers, telecom equipment, and battery-powered IoT devices requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6343LUT+ 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 demanding industrial, automotive, and communications applications.

The MAX6342–MAX6345 family delivers highly accurate, low-power supervisory functions for microprocessor systems requiring robust power monitoring and fail-safe reset generation in compact form factors.

FAQ

What is the exact reset threshold voltage for MAX6343LUT+?

The MAX6343LUT+ has a factory-trimmed VCC reset threshold of 4.63V with a maximum tolerance of ±0.07V over the full -40°C to +125°C temperature range. This value is laser-trimmed during production and specified in the Electrical Characteristics table under "VTH Reset Threshold" for the "L" suffix variant. The threshold remains stable across supply voltages from +1.0V to +5.5V.

Does MAX6343LUT+ support power-fail detection on a secondary supply?

Yes, MAX6343LUT+ supports power-fail detection via its dedicated PFI pin, which connects to an internal +1.25V reference comparator. By applying a scaled version of a secondary supply (e.g., 3.3V or 2.5V rail) through a resistor divider to PFI, the device asserts PFO low when that supply falls below the trip point defined by VTH(PFI) = 1.25 × (R1 + R2)/R2. This enables independent early-warning signaling without affecting the primary reset function.

What is the required external component for MAX6343LUT+ RESET output?

The MAX6343LUT+ RESET pin is an active-low open-drain output and requires an external pull-up resistor to a valid logic-high voltage (up to +5.5V). A 10kΩ resistor is sufficient in most cases, selected to ensure VOL ≤ 0.4V at ISINK = 100µA while maintaining adequate rise time for the target load capacitance. Unlike push-pull variants (e.g., MAX6342LUT+), MAX6343LUT+ cannot drive high without this external component.

Can MAX6343LUT+ operate reliably during deep brownout conditions?

Yes, MAX6343LUT+ guarantees valid RESET assertion down to VCC = +1.0V, as confirmed in the Absolute Maximum Ratings and Electrical Characteristics tables. Its internal bandgap reference and comparator architecture remain functional across the full +1.0V to +5.5V supply range, ensuring deterministic reset behavior even as the main supply collapses-critical for preventing code execution errors in failing power conditions.

Is the MR input of MAX6343LUT+ debounced, and what is its glitch rejection capability?

Yes, the MR input of MAX6343LUT+ is internally debounced with guaranteed rejection of transients shorter than 0.1µs. The datasheet specifies "MR Glitch Rejection" as 0.1µs and "MR Minimum Pulse Width" as 1µs, meaning the device ignores noise spikes below 0.1µs and requires MR to be held low for ≥1µs to initiate a reset. This eliminates need for external RC filters in pushbutton interfaces.