Analog Devices Inc./Maxim Integrated MAX6338IUB

Overview

MAX6338IUB from Maxim Integrated is a quad voltage monitor IC designed for multivoltage system supervision, monitoring +5.0V, +3.3V, +2.5V, and +1.8V supplies with factory-trimmed thresholds at 10% tolerance, consuming only 25µA typical supply current, and operating from +2.5V to +5.5V - used in desktop computers, data storage equipment, and industrial controllers for reliable power-good signaling.

For engineers reviewing the MAX6338IUB datasheet, MAX6338IUB pinout, MAX6338IUB application, or MAX6338IUB equivalent, this device delivers four independent open-drain active-low outputs, internal bandgap reference accuracy over -40°C to +85°C, no external components required, and wire-ORable outputs for consolidated fault reporting in embedded power management systems.

Technical Context

The MAX6338IUB integrates four precision comparators, each with a dedicated input (IN1–IN4) tied to factory-programmed resistive dividers referencing a 1.23V internal bandgap. Thresholds are fixed per pin: IN1 = +5.0V (-10%), IN2 = +3.3V (-10%), IN3 = +2.5V (-10%), IN4 = +1.8V (-10%). Hysteresis is built-in at 0.3%, eliminating external feedback networks.

All outputs (OUT1–OUT4) are open-drain with weak 10µA internal pull-ups to VCC, enabling direct wire-OR connection. An undervoltage lockout circuit forces all outputs low when VCC drops below +2.5V, ensuring deterministic behavior during brownout conditions across the full -40°C to +85°C range.

Key Specifications

Pinout & Package

The MAX6338IUB is housed in a 10-pin µMAX® package (3.0mm × 3.0mm, 0.6mm height), lead-free compatible, with exposed pad for thermal enhancement and standard SOIC footprint compatibility.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV809E33DBZR and ADM1266ACPZ, the MAX6338IUB provides optimal balance of integration, simplicity, and cost for fixed-rail systems - delivering verified quad supervision in one 3mm × 3mm package without software overhead or external components.

Availability

MAX6338IUB is available at Aetrix Electronics and suitable for desktop computers, data storage equipment, and industrial control systems requiring stable component supply, long-lifecycle support, and guaranteed traceability.

Supply support for MAX6338IUB 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 solutions for industrial, computing, and communications markets.

The MAX6338 family was designed specifically for multivoltage system supervision - delivering accurate, low-power, pin-configured voltage monitoring without external components for PC, storage, and embedded applications.

FAQ

What is the exact threshold voltage for each input on the MAX6338IUB?

The MAX6338IUB has factory-programmed thresholds: IN1 = +5.0V at -10% (4.25V to 4.50V), IN2 = +3.3V at -10% (2.85V to 3.00V), IN3 = +2.5V at -10% (2.13V to 2.25V), and IN4 = +1.8V at -10% (1.53V to 1.62V). These values are guaranteed over -40°C to +85°C and include built-in 0.3% hysteresis to prevent oscillation.

Does the MAX6338IUB require external pull-up resistors on its outputs?

No - the MAX6338IUB includes weak 10µA internal pull-ups to VCC on all four open-drain outputs (OUT1–OUT4), enabling direct wire-OR connection without external resistors. External pull-ups may be added to override the internal ones, but they are not required for basic operation or logic interfacing.

Can the MAX6338IUB monitor negative voltages such as -5.0V?

No - the MAX6338IUB variant IUB is configured exclusively for +5.0V, +3.3V, +2.5V, and +1.8V positive rail monitoring. For -5.0V supervision, select MAX6338MUB, MAX6338NUB, MAX6338OUB, or MAX6338PUB variants, which include dedicated -5V input capability and appropriate threshold polarity.

What happens to the outputs of the MAX6338IUB when VCC drops below 2.5V?

When VCC drops below +2.5V, the internal undervoltage lockout (UVLO) circuit forces all four outputs (OUT1–OUT4) low, regardless of input voltage states. This ensures predictable, fail-safe behavior during brownout or power-down sequences - a critical feature for controlled system resets in the MAX6338IUB.

Is the MAX6338IUB pin-compatible with other variants in the MAX6338 family?

No - while all MAX6338 variants share the same 10-pin µMAX package and pinout, the internal threshold configurations differ per part number. The MAX6338IUB is not functionally interchangeable with variants like MAX6338JUB (5%/5%/5%/5% tolerance) or MAX6338HUB (5%/5%/1.8V/1.8V), as threshold assignments and tolerances are factory-programmed and non-adjustable.