Analog Devices Inc./Maxim Integrated MAX6339JUT+T

Overview

MAX6339JUT+T from Maxim Integrated is a quad voltage supervisory IC that monitors +5.0V (−5%), +3.3V (−5%), +2.5V (−5%), and +1.8V (−5%) supply rails with precision factory-trimmed thresholds, delivers a single active-low open-drain RESET output, and operates from IN2 with 55µA supply current in a 6-pin SOT23 package for embedded power integrity in telecom and computing systems.

For engineers reviewing the MAX6339JUT+T datasheet, MAX6339JUT+T pinout, MAX6339JUT+T application, or MAX6339JUT+T equivalent, key selection criteria include guaranteed −40°C to +85°C operation, 140ms min reset timeout, immunity to short supply transients, no external components required for fixed-threshold monitoring, and valid RESET assertion down to IN1 or IN2 = 1V.

Technical Context

The MAX6339JUT+T integrates four precision comparators with an internal 1.23V bandgap reference and factory-trimmed resistor-divider networks to set exact thresholds for each input: IN1 = +5.0V (−5%), IN2 = +3.3V (−5%), IN3 = +2.5V (−5%), IN4 = +1.8V (−5%). All comparators feature 0.3% hysteresis to reject noise without degrading accuracy at threshold crossing.

RESET is open-drain with a 10µA internal pullup to IN2, remains asserted for ≥140ms after all inputs recover, and stays valid as long as IN1 ≥ 1V or IN2 ≥ 1V - enabling reliable reset hold during brownout recovery in multi-rail systems powered from IN2.

Key Specifications

Pinout & Package

Package: 6-pin SOT23-6, surface-mount, 2.9mm × 1.6mm footprint, 1.1mm max height, lead-free (RoHS-compliant) per +T suffix.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6340JUT+T and TPS3307-33D, the MAX6339JUT+T provides optimal cost-performance balance for pure quad-rail voltage monitoring without added complexity - delivering precise −5% thresholds on all four rails, guaranteed 140ms timeout, and minimal external component count in a proven SOT23 footprint.

Availability

MAX6339JUT+T is available at Aetrix Electronics and suitable for telecommunications base stations, industrial PLC controllers, network attached storage systems, and high-end multifunction printers requiring stable component supply and guaranteed long-term availability.

Supply support for MAX6339JUT+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 MAX6339JUT+T belongs to Maxim's µP supervisory circuit product line, engineered specifically to replace discrete reset solutions in multi-rail systems where space, reliability, and deterministic reset timing are critical.

FAQ

What is the exact threshold voltage for each input on the MAX6339JUT+T?

The MAX6339JUT+T has factory-trimmed thresholds: IN1 = +5.0V (−5% → 4.50V–4.75V), IN2 = +3.3V (−5% → 2.85V–3.00V), IN3 = +2.5V (−5% → 2.13V–2.25V), IN4 = +1.8V (−5% → 1.53V–1.62V). These values are fully specified over −40°C to +85°C and include 0.3% hysteresis. The MAX6339JUT+T datasheet Table 1 lists min/typ/max for each under "Reset Threshold Voltage".

Does the MAX6339JUT+T require external resistors to monitor its designated voltages?

No, the MAX6339JUT+T requires no external components to monitor its four designated rails (+5.0V, +3.3V, +2.5V, +1.8V) at −5% tolerance. Its internal precision resistor-divider networks and bandgap reference eliminate external trimming. External resistors are only needed if user-adjustable thresholds are selected - which the MAX6339JUT+T does not implement.

How does the RESET output behave when IN2 drops below 1V?

When IN2 falls below 1V, the MAX6339JUT+T RESET output becomes undefined - the device cannot guarantee correct logic state. However, as long as either IN1 ≥ 1V or IN2 ≥ 1V, RESET remains valid and correctly asserted or deasserted. This allows the MAX6339JUT+T to maintain reset control during partial brownout conditions common in multi-rail systems.

Can the MAX6339JUT+T monitor negative voltages like −5V?

No, the MAX6339JUT+T is configured exclusively for positive rail monitoring: +5.0V, +3.3V, +2.5V, and +1.8V, all at −5% tolerance. Negative voltage monitoring (e.g., −5V) is supported only in other variants such as MAX6339MUT+T or MAX6339NUT+T. The MAX6339JUT+T pinout and internal trim do not accommodate negative thresholds.

What is the maximum capacitive load the MAX6339JUT+T RESET output can drive?

The MAX6339JUT+T RESET output is an open-drain structure with a weak 10µA internal pullup to IN2. It is designed to drive standard CMOS inputs (≤10pF) directly. For heavier loads (>50pF) or faster edge rates, an external pullup resistor (e.g., 10kΩ to IN2 or another logic rail) is recommended. The MAX6339JUT+T datasheet Figure 6 characterizes pullup/pulldown response with 47pF load.