Analog Devices Inc./Maxim Integrated MAX6338MUB+

Overview

The MAX6338MUB+ from Maxim Integrated is a quad voltage monitor IC designed to supervise four independent power rails in multivoltage systems. It monitors +5.0V, +3.0V, adjustable (via resistor divider), and -5.0V supplies with factory-trimmed thresholds, 10% tolerance, 25µA typical supply current, and operates from +2.5V to +5.5V over -40°C to +85°C - used in telecom and industrial equipment for reliable power-good signaling.

For engineers reviewing the MAX6338MUB+ datasheet, MAX6338MUB+ pinout, MAX6338MUB+ application, or MAX6338MUB+ equivalent, key selection considerations include its open-drain active-low outputs, internal 1.23V bandgap reference, wire-OR capability, undervoltage lockout below 2.5V, and support for negative voltage monitoring without external components.

Technical Context

The MAX6338MUB+ integrates four independent comparators, each with a dedicated input and open-drain output. Inputs IN1–IN4 are configured for +5.0V, +3.0V, adjustable (AUX), and -5.0V monitoring respectively, with trip thresholds set by internal resistor dividers or external feedback for the AUX channel.

It uses an internal 1.23V bandgap reference for positive-voltage thresholds and direct comparator access for the -5.0V input. Hysteresis is built-in (0.3%), eliminating external feedback networks, and undervoltage lockout forces all outputs low when VCC drops below 2.5V - ensuring clean reset behavior during brownout conditions.

Key Specifications

Pinout & Package

The MAX6338MUB+ is housed in a 10-pin µMAX® package (3.0mm × 3.0mm, 0.6mm height), RoHS-compliant and available in lead-free format (+ suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6340MUB+ and TPS3307-33DGNR, the MAX6338MUB+ uniquely delivers factory-configured -5.0V supervision alongside three other rails in one µMAX package - enabling compact, fully self-contained quad monitoring without external components or layout compromises.

Availability

MAX6338MUB+ is available at Aetrix Electronics and suitable for telecommunications infrastructure, industrial PLCs, medical imaging subsystems, and test & measurement equipment requiring stable component supply and long-term lifecycle support.

Supply support for MAX6338MUB+ 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 MAX6338 series belongs to Maxim's power-supervisory product line, engineered specifically for multirail system-level power integrity verification in space-constrained, high-reliability environments.

FAQ

What voltage rails does the MAX6338MUB+ monitor?

The MAX6338MUB+ monitors four specific rails: +5.0V (IN1), +3.0V (IN2), an adjustable voltage (IN3) set via external resistor divider using the internal 1.23V reference, and -5.0V (IN4). Thresholds are factory-trimmed for 10% tolerance on all channels, and the -5.0V input supports a -6V to +0.3V input range.

Does the MAX6338MUB+ require external components for basic operation?

No - the MAX6338MUB+ requires zero external components for monitoring its factory-configured +5.0V, +3.0V, and -5.0V inputs. Only the adjustable input (IN3) needs two external resistors to set the desired threshold. A 0.1µF bypass capacitor on VCC is recommended for noisy environments but not strictly required for functionality.

How do the open-drain outputs of the MAX6338MUB+ interface with system logic?

The MAX6338MUB+ provides four open-drain, active-low outputs (OUT1–OUT4), each with a 10µA internal pull-up to VCC. They can directly drive 1.8V, 3.3V, or 5V logic inputs and support wire-OR connection - allowing multiple outputs to share a single pull-up resistor and generate a composite "power good" signal without additional gates or level shifters.

What happens to MAX6338MUB+ outputs during VCC brownout?

The MAX6338MUB+ includes an internal undervoltage lockout (UVLO) circuit that forces all four outputs low whenever VCC drops below 2.5V. This ensures deterministic reset behavior during power ramp-down or brownout events, preventing spurious logic states in downstream circuitry until VCC stabilizes within specification.

Can the MAX6338MUB+ monitor voltages other than those listed in the selector guide?

Yes - the MAX6338MUB+ supports user-defined thresholds via its auxiliary input (IN3), which connects directly to the noninverting comparator terminal. Using an external resistor divider referenced to the internal 1.23V bandgap, designers can configure IN3 to monitor any positive voltage from ~1.3V to >5.5V. The -5.0V input (IN4) is fixed and cannot be reconfigured.