Analog Devices Inc./Maxim Integrated MAX6344LUT

Overview

MAX6344LUT from Maxim Integrated is a precision microprocessor supervisory circuit in SOT23-6 package, providing active-high push-pull reset output, factory-trimmed 4.63V V_CC reset threshold, +1.25V power-fail comparator input (PFI), and guaranteed RESET validity down to V_CC = +1V. It monitors supply integrity in multivoltage embedded systems and enables orderly shutdown during brownout or low-battery conditions.

For engineers reviewing the MAX6344LUT datasheet, MAX6344LUT pinout, MAX6344LUT application, or MAX6344LUT equivalent, this device is selected for its precise reset threshold tolerance (±25mV over temperature), 100ms minimum reset timeout, debounced manual-reset input, and dual-monitoring capability via PFI/PFO for auxiliary supply or battery voltage tracking.

Technical Context

The MAX6344LUT integrates a precision bandgap reference, comparator-based reset generator, and independent power-fail detection circuitry. Its reset assertion logic responds to V_CC falling below 4.63V ±25mV or MR being pulled low, with internal timing ensuring ≥100ms (min) reset pulse width across –40°C to +125°C.

The PFI input connects to an internal +1.25V reference, enabling external voltage monitoring via resistor divider; PFO asserts low when PFI < 1.25V. Unlike MAX6342/MAX6343, MAX6344LUT features only active-high push-pull RESET output - no MR input or open-drain option - simplifying interface to µP reset pins requiring high-active assertion.

Key Specifications

Pinout & Package

MAX6344LUT is housed in a lead-free, RoHS-compliant 6-pin SOT23 package (JEDEC MO-178AA). Pin 1 is marked with a dot; pin numbering follows standard SOT23 top-view convention.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6342LUT, MAX6344LUT removes MR and delivers active-high RESET - reducing BOM count and simplifying µP interface but eliminating manual override. Versus TLV803SDBZR, MAX6344LUT adds full power-fail comparator capability at higher ICC, making it appropriate for systems requiring dual-supply awareness.

Availability

MAX6344LUT is available at Aetrix Electronics and suitable for portable/battery-powered equipment, telecom equipment, and multivoltage systems requiring stable component supply, extended temperature operation, and precise reset threshold control.

Supply support for MAX6344LUT 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, automotive, communications, and computing applications.

The MAX6342–MAX6345 family was developed to replace discrete reset solutions in space-constrained, high-reliability digital systems - delivering factory-calibrated thresholds, integrated power-fail detection, and guaranteed operation across extreme temperatures.

FAQ

What is the exact reset threshold voltage of MAX6344LUT?

The MAX6344LUT has a factory-trimmed V_CC reset threshold of 4.63V, with a maximum deviation of ±25mV over the full operating temperature range (–40°C to +125°C). This value is laser-trimmed during production and specified in the Electrical Characteristics table under "V_TH Reset Threshold" for the "L" suffix variant. The "L" in MAX6344LUT explicitly denotes the 4.63V threshold option.

Does MAX6344LUT include a manual-reset (MR) input?

No, MAX6344LUT does not include a manual-reset (MR) input. Per the Pin Description and Selector Guide, only MAX6342, MAX6343, and MAX6345 feature MR functionality. MAX6344LUT is configured exclusively with active-high push-pull RESET output and lacks both MR and active-low RESET terminals - confirmed by its pinout (Pin 5 = RESET, Pin 6 = NC) and functional diagram.

How is the PFI input used in MAX6344LUT?

In MAX6344LUT, the PFI (Pin 3) connects to an internal +1.25V reference comparator. When the voltage at PFI falls below 1.25V, PFO (Pin 4) asserts low. To monitor a secondary supply (e.g., 3.3V), a resistor divider scales that voltage so it crosses 1.25V just before the monitored rail fails. This enables early-warning interrupts independent of the main reset function - a capability unique to the MAX6342–MAX6345 family.

What is the reset timeout duration for MAX6344LUT?

The MAX6344LUT guarantees a minimum reset timeout period (t_RP) of 100ms after V_CC rises above the 4.63V threshold or after a valid reset condition clears. Typical duration is 180ms, with a maximum of 280ms across –40°C to +125°C. This timing is internally generated and does not require external components - ensuring compliance with µP reset hold-time requirements without design overhead.

Is MAX6344LUT compatible with lead-free PCB assembly processes?

Yes, MAX6344LUT is available in lead-free packaging. The "-T" suffix indicates leaded packaging; to specify lead-free, replace "-T" with "+T" in the order code (e.g., MAX6344LUT+T). The device meets RoHS Directive 2011/65/EU and is qualified for standard Pb-free reflow profiles, including peak temperatures up to +260°C for 10 seconds - as documented in Maxim's package information and reliability reports.