Analog Devices Inc./Maxim Integrated MAX6338IUB+T

Overview

The MAX6338IUB+T 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 10% tolerance thresholds. It consumes 25µA typical supply current, operates from +2.5V to +5.5V, and delivers four independent open-drain active-low outputs in a 10-pin µMAX package-used in desktop computers, networking equipment, and industrial systems for reliable power-good signaling.

For engineers reviewing the MAX6338IUB+T datasheet, MAX6338IUB+T pinout, MAX6338IUB+T application, or MAX6338IUB+T equivalent, key selection criteria include its fixed 4-input voltage configuration (+5V/+3.3V/+2.5V/+1.8V), guaranteed -40°C to +85°C operation, internal bandgap reference accuracy, wire-ORable outputs, and absence of external components for threshold setting.

Technical Context

The MAX6338IUB+T integrates four independent comparators, each with an inverting input tied to a precision 1.23V bandgap reference and noninverting inputs connected via internal resistor dividers set for nominal voltages. Thresholds are factory-trimmed for ±10% tolerance on all four inputs, eliminating calibration overhead.

Its undervoltage lockout (UVLO) circuit forces all outputs low when VCC drops below +2.5V, ensuring deterministic behavior during brownout. Outputs feature weak 10µA internal pull-ups to VCC and support wire-OR connection without external logic-enabling single "power good" bus generation across multiple rails.

Key Specifications

Pinout & Package

The MAX6338IUB+T is housed in a 10-pin µMAX® package (3.0mm × 3.0mm, 0.5mm pitch), thermally enhanced with exposed pad (not electrically connected), compatible with standard reflow profiles and high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6338IUB+T, the MAX6340EUB+T offers tighter threshold accuracy at higher current cost, while the TPS3307-33DGNR sacrifices integration density and true quad capability-making MAX6338IUB+T optimal for space-constrained, cost-sensitive multirail systems requiring −10% tolerance compliance.

Availability

MAX6338IUB+T is available at Aetrix Electronics and suitable for desktop computers, networking equipment, and industrial PLC controllers requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant lead-free packaging.

Supply support for MAX6338IUB+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 industrial, computing, communications, and automotive markets.

The MAX6338 family delivers compact, low-power quad voltage supervision for multirail digital systems-targeting applications where board space, power budget, and supply tolerance compliance are tightly constrained.

FAQ

What voltage thresholds does the MAX6338IUB+T monitor?

The MAX6338IUB+T monitors +5.0V, +3.3V, +2.5V, and +1.8V nominal supplies, each with a −10% trip threshold: 4.50V, 2.97V, 2.25V, and 1.62V respectively. These values are factory-trimmed and do not require external components. The MAX6338IUB+T uses an internal 1.23V bandgap reference and precision resistor dividers to achieve this fixed configuration-confirmed in the Selector Guide and Electrical Characteristics table.

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

No-the MAX6338IUB+T includes weak 10µA internal pull-ups to VCC on all four open-drain outputs (OUT1–OUT4), enabling direct connection to logic inputs without external components. External pull-ups may be added to override the internal ones-for example, to interface with 3.3V logic while VCC is 5V-but they are not required for basic operation. This behavior is specified in the Pin Description and Applications Information sections.

Can the MAX6338IUB+T be used in systems with only three monitored rails?

Yes-the MAX6338IUB+T supports unused inputs: IN1–IN4 not connected to active supplies should be tied to GND or left floating (except AUX inputs, which do not apply here). The device's internal resistor dividers terminate unused positive-rail inputs to ground, preventing false triggering. This is documented in the "Unused Inputs" section and validated across all MAX6338 variants including MAX6338IUB+T.

What is the minimum operating voltage for the MAX6338IUB+T's VCC pin?

The MAX6338IUB+T requires a minimum VCC of +2.5V to operate; below this, its undervoltage lockout (UVLO) circuit forces all outputs low regardless of input conditions. The device remains functional down to VCC = +1V, but outputs stay asserted low until VCC rises above +2.5V. This behavior is explicitly defined in the Absolute Maximum Ratings and Pin Description tables for MAX6338IUB+T.

Is the MAX6338IUB+T pin-compatible with other MAX6338 variants like MAX6338JUB+T?

Yes-MAX6338IUB+T shares identical pinout, package (10-pin µMAX), and terminal functions with all MAX6338_UB variants, including MAX6338JUB+T. Differences lie solely in factory-programmed threshold voltages and tolerances (e.g., JUB uses −5% tolerance on +1.8V and +2.5V rails), not pin assignment or electrical interface. This compatibility is confirmed in the Selector Guide and Pin Configuration diagram.