Analog Devices Inc./Maxim Integrated MAX6709LUB+T

Overview

MAX6709LUB+T from Maxim Integrated is a quad voltage monitor IC for multivoltage systems, featuring four independent active-low open-drain outputs with 10µA internal pullup to VCC, factory-trimmed thresholds for 3.3V and 1.8V nominal supplies (±5% tolerance), and adjustable inputs down to 0.62V. It consumes only 35µA typical supply current and operates from 2.0V to 5.5V over –40°C to +85°C - used in desktop computers and networking equipment for power-good supervision.

For engineers reviewing the MAX6709LUB+T datasheet, MAX6709LUB+T pinout, MAX6709LUB+T application, or MAX6709LUB+T equivalent, this page delivers verified electrical parameters, µMAX package layout, real-world use cases, and validated alternative parts - all confirmed against Maxim's official documentation for accurate system-level design and BOM selection.

Technical Context

The MAX6709LUB+T implements four precision comparators with an internal 0.62V bandgap reference and factory-configured resistor-divider networks for fixed-threshold monitoring of 3.3V and 1.8V supplies. Its two adjustable inputs (IN1 and IN4) accept external resistor dividers to set custom thresholds as low as 0.62V, while hysteresis is built-in at 0.3% of threshold voltage.

All outputs are open-drain with weak 10µA internal pullups to VCC, enabling wire-ORed power-good signaling without external components. An undervoltage lockout circuit forces all PWRGD_ outputs low when VCC drops below 2.0V, ensuring reliable behavior down to 1V operation per test data.

Key Specifications

Pinout & Package

MAX6709LUB+T is housed in a 10-pin µMAX package (3.0mm × 3.0mm, 0.6mm height), lead-free, with exposed pad for thermal performance. Pin 5 is GND; Pin 10 is VCC; Pins 1, 2, 3, 4 are input terminals; Pins 6–9 are corresponding open-drain outputs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6705LUB+T and TPS3307-33DGNR, the MAX6709LUB+T uniquely delivers four fully independent monitoring channels with two adjustable inputs in a single µMAX package - essential for compact, multivoltage systems requiring complete rail visibility without cascading devices or external hysteresis networks.

Availability

MAX6709LUB+T is available at Aetrix Electronics and suitable for desktop computers, network switches, industrial printers, and storage controllers requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.

Supply support for MAX6709LUB+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 and mixed-signal ICs for power, sensing, and interface applications - known for high-accuracy voltage references and supervisory circuits.

The MAX6709LUB+T belongs to Maxim's low-power quad voltage monitor product line, engineered specifically for reliable, component-minimized power-supply supervision in multivoltage computing and communications platforms.

FAQ

What is the function of the adjustable inputs on the MAX6709LUB+T?

The MAX6709LUB+T features two adjustable inputs (IN1 and IN4) that accept external resistor-divider networks to set custom voltage thresholds as low as 0.62V. Each connects directly to a comparator referenced to the internal 0.62V bandgap, enabling precise monitoring of nonstandard rails like 2.8V or 1.2V. Unused adjustable inputs must be tied to GND to prevent floating nodes.

Does the MAX6709LUB+T provide hysteresis, and how is it implemented?

Yes, the MAX6709LUB+T integrates 0.3% of threshold voltage hysteresis internally - eliminating the need for external positive-feedback resistors. This hysteresis prevents output oscillation during slow-moving or noisy input transitions near trip points, ensuring clean, glitch-free PWRGD assertions without additional components.

Can the MAX6709LUB+T outputs drive standard logic interfaces directly?

Yes, all four PWRGD outputs on the MAX6709LUB+T are active-low open-drain with 10µA internal pullup to VCC, allowing direct connection to 1.8V, 3.3V, or 5V logic families. External pullups are optional and only needed when interfacing to higher-voltage domains; internal pullups eliminate the need for discrete resistors in same-supply applications.

What is the minimum operating voltage for the MAX6709LUB+T, and what happens below it?

The MAX6709LUB+T operates from 2.0V to 5.5V. Below 2.0V, its internal undervoltage lockout circuit forces all PWRGD outputs low - maintaining a known fault state even as VCC decays to 1V. This behavior ensures predictable system response during brownout conditions and prevents erratic output toggling.

How does the MAX6709LUB+T differ from the MAX6714 series?

The MAX6709LUB+T is a pure quad voltage monitor with four independent PWRGD outputs and no reset timing or manual reset input. In contrast, the MAX6714 integrates a timed RESET output, MR input, and three PFI/PFO channels - making it a supervisor with reset functionality. The MAX6709LUB+T is selected when discrete, simultaneous power-good signals are required without reset logic overhead.