Analog Devices Inc./Maxim Integrated MAX6344MUT+T

Overview

MAX6344MUT+T from Maxim Integrated is an active-high push-pull µP supervisory circuit in a 6-pin SOT23 package, designed to monitor VCC supply voltage and assert reset when VCC falls below 3.08V (factory-trimmed threshold), guaranteeing valid RESET output down to VCC = +1V with ≥100ms reset pulse width. It integrates a dedicated power-fail comparator (PFI/PFO) for low-battery or auxiliary supply monitoring in portable and multivoltage systems.

For engineers reviewing the MAX6344MUT+T datasheet, MAX6344MUT+T pinout, MAX6344MUT+T application, or MAX6344MUT+T equivalent, key selection criteria include its active-high push-pull RESET output, factory-set 3.08V reset threshold, guaranteed operation over –40°C to +125°C, 6-pin SOT23 footprint, and integrated PFI/PFO comparator for independent power-fail warning.

Technical Context

The MAX6344MUT+T implements a precision bandgap-based reset threshold detector with ±25mV accuracy over temperature, paired with a monostable reset timer that ensures ≥100ms (min) reset assertion after VCC rise or MR deassertion. Its PFI input connects to an internal 1.25V reference, enabling configurable power-fail detection via external resistor dividers.

Unlike the MAX6342/MAX6343 variants, the MAX6344MUT+T omits MR input and active-low RESET, instead providing only an active-high push-pull RESET output - eliminating need for external pull-up resistors while supporting direct interface to µP reset inputs requiring high-true assertion. All logic thresholds are CMOS-compatible across full VCC range (1.0V–5.5V).

Key Specifications

Pinout & Package

Package: 6-pin SOT23-6 (1.6mm × 2.9mm × 1.1mm), surface-mount, lead-free (RoHS-compliant), top-mark "AADR".

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6344MUT+T, the MAX6344TUT+T is electrically identical with minor marking variance, whereas the TPS3808G30DBVR sacrifices PFI/PFO integration and requires external pull-up-making it suitable only when power-fail monitoring is omitted and layout allows open-drain adaptation.

Availability

MAX6344MUT+T is available at Aetrix Electronics and suitable for portable computers, telecom equipment, and embedded control systems requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MAX6344MUT+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, mixed-signal, and power management ICs for demanding industrial, automotive, and communications applications.

The MAX6342–MAX6345 family delivers highly accurate, low-power µP supervision with integrated power-fail detection-targeting space-constrained, battery-sensitive, and thermally harsh environments where reliability and deterministic reset timing are critical.

FAQ

What is the exact reset threshold voltage of the MAX6344MUT+T?

The MAX6344MUT+T has a factory-trimmed reset threshold of 3.08V, with guaranteed tolerance 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 VTH parameter for the 'M' threshold variant. The MAX6344MUT+T does not require external components to set this threshold.

Does the MAX6344MUT+T include a manual reset (MR) input?

No, the MAX6344MUT+T does not include a manual reset (MR) input. Per the Pin Configurations table and Functional Diagrams, the MAX6344 variant replaces the MR pin (pin 5 on MAX6342/MAX6343) with NC (no connect), and pin 6 is unused. Only the MAX6342, MAX6343, and MAX6345 include MR functionality-the MAX6344MUT+T is optimized for automatic reset-only operation.

What is the function of the PFI and PFO pins on the MAX6344MUT+T?

The PFI (Pin 3) is the power-fail input, internally referenced to a precise +1.25V comparator threshold. When voltage at PFI falls below 1.25V, the PFO (Pin 4) output goes low. This enables independent monitoring of secondary supplies (e.g., battery, 5V rail) using an external resistor divider. The MAX6344MUT+T uses PFO as an open-drain active-low signal, requiring an external pull-up resistor for logic-level interfacing.

Can the MAX6344MUT+T operate reliably during deep brownout conditions?

Yes, the MAX6344MUT+T guarantees valid RESET output down to VCC = +1V, as confirmed in the Absolute Maximum Ratings and Electrical Characteristics tables. Its internal circuitry remains functional and asserts RESET correctly even as VCC collapses-critical for preventing MCU runaway during severe undervoltage events. This behavior is explicitly tested and specified, unlike many supervisors that fail below 2.0V.

What package and marking does the MAX6344MUT+T use?

The MAX6344MUT+T is supplied in a 6-pin SOT23-6 package (1.6mm × 2.9mm × 1.1mm) with lead-free (RoHS-compliant) finish. Its top-side marking is "AADR", as documented in the SOT Top Marks table. The "+T" suffix indicates lead-free packaging, and "M" denotes the 3.08V reset threshold variant-distinct from 'L' (4.63V), 'T' (3.08V alternate marking), or 'Z' (2.33V).