Analog Devices Inc./Maxim Integrated MAX6339HUT+T

Overview

MAX6339HUT+T from Maxim Integrated is a precision quad voltage supervisory IC that monitors +5.0V, +3.0V, +1.8V (±5% tolerance), and one user-adjustable input using an internal 1.23V reference. It asserts a single active-low open-drain RESET output when any monitored supply falls below its threshold, with guaranteed operation down to IN1 or IN2 ≥ 1V and a minimum 140ms reset timeout. It targets multi-rail embedded systems requiring compact, low-power supply integrity monitoring.

For engineers reviewing the MAX6339HUT+T datasheet, MAX6339HUT+T pinout, MAX6339HUT+T application, or MAX6339HUT+T equivalent, key selection considerations include its fixed +5.0V/–5%, +3.0V/–5%, +1.8V/–5% thresholds, adjustable fourth input, 55µA supply current, SOT23-6 package, and immunity to short supply transients.

Technical Context

The MAX6339HUT+T integrates four precision comparators with a bandgap reference and factory-trimmed resistor-divider networks for its three fixed thresholds (+5.0V, +3.0V, +1.8V), each with 0.3% hysteresis. Its fourth input (IN4) bypasses internal dividers and connects directly to a comparator with a 1.23V ±30mV threshold, enabling external resistor-divider configuration for nonstandard voltages.

Power is derived solely from IN2 (+3.0V in this variant), which also serves as the internal pullup source for the open-drain RESET output (10µA typical). The device guarantees valid RESET assertion and release across –40°C to +85°C, with RESET remaining low for ≥140ms after all inputs recover above their thresholds.

Key Specifications

Pinout & Package

The MAX6339HUT+T is housed in a 6-pin SOT23-6 package (JEDEC MO-178AA), measuring 2.9mm × 1.6mm × 1.1mm, with gull-wing leads and lead-free (RoHS-compliant) finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6340HUT+T and TPS3307-33D, the MAX6339HUT+T uniquely delivers true quad-rail supervision with one user-adjustable input in a standard SOT23-6 footprint-enabling compact, flexible power integrity management without added complexity or layout changes.

Availability

MAX6339HUT+T is available at Aetrix Electronics and suitable for telecommunications infrastructure, industrial PLCs, high-end printers, and data storage controllers requiring stable component supply and long-term production continuity.

Supply support for MAX6339HUT+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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and computing markets.

The MAX6339HUT+T belongs to Maxim's µP supervisory product line, designed specifically for space-constrained, multi-supply systems needing precise, low-power voltage monitoring with minimal external components.

FAQ

What voltage rails does the MAX6339HUT+T monitor?

The MAX6339HUT+T monitors +5.0V (–10% threshold), +3.0V (–10% threshold), +1.8V (–10% threshold), and one user-adjustable input referenced to 1.23V. These settings are confirmed by the "H" suffix in the Selector Guide, indicating IN1 = +5V, IN2 = +3.0V, IN3 = +1.8V, and IN4 = adjustable. No external components are needed for the three fixed thresholds.

How is the adjustable input (IN4) configured on the MAX6339HUT+T?

The MAX6339HUT+T IN4 pin connects directly to a comparator with a 1.23V ±30mV internal reference. To monitor a custom voltage V_IN4, use an external resistor divider where V_IN4 = 1.23V × (R1 + R2)/R2. With ±0.1µA input current, R2 values up to 100kΩ maintain <1% error. This configuration is explicitly defined in the MAX6339HUT+T datasheet Figure 4 and Selector Guide.

What is the reset timeout period for the MAX6339HUT+T, and how is it guaranteed?

The MAX6339HUT+T provides a minimum reset timeout period of 140ms after all monitored inputs exceed their thresholds, with typical and maximum values of 200ms and 280ms respectively. This timing is internally generated and guaranteed over the full –40°C to +85°C operating range, as specified in the Electrical Characteristics table under "Reset Active Timeout Period (t_RP)".

Can the MAX6339HUT+T operate if one supply rail drops below 1V?

Yes-the MAX6339HUT+T RESET output remains valid and asserted as long as either IN1 ≥ 1V or IN2 ≥ 1V. This is explicitly guaranteed in Note 3 of the Electrical Characteristics section and enables reliable reset assertion during partial brown-out conditions, a key requirement for robust system recovery.

Is the MAX6339HUT+T pin-compatible with other MAX6339 variants?

Yes-all MAX6339 variants, including MAX6339HUT+T, share identical 6-pin SOT23-6 pinout and electrical interface. Differences lie only in factory-programmed threshold configurations (e.g., IN1/IN2/IN3 voltage assignments and tolerances), not pin function or package. This allows drop-in replacement across variants when board layout supports the required rail assignments.