Analog Devices Inc./Maxim Integrated MAX6339PUT+T

Overview

MAX6339PUT+T from Maxim Integrated is a quad voltage supervisory IC that monitors +5.0V, +3.3V, adjustable, and -5.0V supplies with ±5% tolerance, delivers 140ms minimum reset timeout, consumes 55µA supply current, and features open-drain RESET with 10µA internal pullup to IN2 - used in telecom and industrial multi-rail systems for reliable µP reset assertion.

For engineers reviewing the MAX6339PUT+T datasheet, MAX6339PUT+T pinout, MAX6339PUT+T application, or MAX6339PUT+T equivalent, key selection criteria include factory-trimmed dual fixed thresholds (+5.0V/-5.0V), user-adjustable inputs (IN3/IN4), guaranteed operation down to IN1 or IN2 = 1V, immunity to short transients, and SOT23-6 footprint compatibility with space-constrained embedded designs.

Technical Context

The MAX6339PUT+T integrates four precision comparators with an internal 1.23V bandgap reference and factory-trimmed resistor-divider networks for fixed thresholds (+5.0V at -5%, -5.0V at +5%). Its IN2 pin serves as both monitored supply and device power source, enabling self-powered supervision without auxiliary bias.

Reset assertion is combinatorial across all inputs: any undervoltage (or overvoltage for -5V input) triggers active-low open-drain RESET, which remains asserted for ≥140ms after all inputs recover. Built-in 0.3% threshold hysteresis and transient immunity (≤100µs glitches rejected per typical curves) ensure noise robustness in noisy power environments.

Key Specifications

Pinout & Package

The MAX6339PUT+T is housed in a 6-pin SOT23-6 package (2.9mm × 1.6mm × 1.1mm), optimized for high-density PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6340PUT+T and TPS3307-33DGNR, the MAX6339PUT+T uniquely combines factory-set +5.0V (–10%) and -5.0V (+5%) thresholds with two adjustable inputs in SOT23-6, delivering optimal trade-off between precision, negative-rail support, and board-space efficiency for multi-supply telecom and industrial systems.

Availability

MAX6339PUT+T is available at Aetrix Electronics and suitable for telecommunications equipment, industrial control systems, and network attached storage requiring stable component supply with guaranteed long-term availability and lead-free compliance.

Supply support for MAX6339PUT+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, communications, and computing applications.

The MAX6339PUT+T belongs to Maxim's µP supervisory product line, engineered specifically for compact, low-power, multi-rail voltage monitoring in space-constrained systems where reliability under voltage transients is critical.

FAQ

What is the exact threshold voltage for the -5.0V input on the MAX6339PUT+T?

The MAX6339PUT+T has a factory-trimmed -5.0V input threshold with +5% tolerance, meaning it asserts RESET when the IN4 voltage rises above -4.50V (typical -4.63V, max -4.25V). This is explicitly confirmed in the Electrical Characteristics table under "-5V (+5%) threshold" and matches the "5" suffix in the Selector Guide for the PUT variant.

Can the MAX6339PUT+T monitor a +2.5V rail, and how is it configured?

Yes - the MAX6339PUT+T uses its IN3 pin as a user-adjustable input. To monitor +2.5V, connect a resistor divider such that V_IN3 = 1.23V × (R1 + R2)/R2 = 2.5V. With R2 = 100kΩ, R1 ≈ 103kΩ. The internal 1.23V reference and ±0.1µA input current enable accurate scaling without calibration.

Does the MAX6339PUT+T require an external pullup resistor on the RESET pin?

No - the MAX6339PUT+T includes a 10µA internal pullup to IN2, sufficient to drive standard CMOS inputs when interfacing with logic powered from the same IN2 rail. An external pullup is only needed when RESET must interface with a different voltage domain (e.g., +5V logic), and even then, the internal circuit prevents reverse current into IN2.

What is the minimum supply voltage required for the MAX6339PUT+T to maintain valid RESET output state?

The MAX6339PUT+T guarantees correct RESET output state as long as either IN1 ≥ 1.0V or IN2 ≥ 1.0V - confirmed in Note 3 of the Electrical Characteristics table and the Pin Description. This ensures deterministic reset behavior during deep brownout conditions where only one rail remains marginally active.

How does the MAX6339PUT+T handle short-duration supply transients?

The MAX6339PUT+T rejects transients ≤100µs (per Figure MAX6339toc04), thanks to internal filtering and 0.3% threshold hysteresis. This prevents false resets during switching noise, motor commutation, or ESD events - a key reliability feature validated in Typical Operating Characteristics.