Analog Devices Inc./Maxim Integrated MAX6888QETE+

Overview

The MAX6888QETE+ from Maxim Integrated is a quad-voltage, overvoltage/undervoltage supervisory IC with integrated watchdog timer, active-low open-drain RESET/OV/WDO outputs, ±1% threshold accuracy, and 16-pin thin QFN package. It monitors four adjustable supply rails (IN1–IN4), asserts RESET on any undervoltage event or manual reset, and supports system-level margin testing via MARGIN input - used in telecom power management and server board monitoring.

For engineers reviewing the MAX6888QETE+ datasheet, MAX6888QETE+ pinout, MAX6888QETE+ application, or MAX6888QETE+ equivalent, key selection criteria include its factory-configured 0.557V undervoltage / 0.643V overvoltage thresholds per input, 200ms RESET timeout, 1.6s normal watchdog period, and compatibility with multirail systems requiring precise supply fault detection and recovery sequencing.

Technical Context

The MAX6888QETE+ implements four independent voltage detectors, each with matched undervoltage and overvoltage comparators referenced to an internal 0.6V bandgap, enabling user-defined thresholds via external resistor dividers. Its watchdog timer features dual-mode operation: 102.4s initial timeout for processor boot initialization, then 1.6s normal timeout for runtime supervision.

All three outputs - RESET, OV, and WDO - are active-low, open-drain, with guaranteed VOL ≤ 0.4V at 4mA sink current and leakage < ±1µA in high-impedance state. The device derives internal power from the highest of IN1–IN4 (≥2.7V) or externally supplied VCC, with BP providing a regulated +2.55V internal logic supply.

Key Specifications

Pinout & Package

Package: 5mm × 5mm × 0.8mm, 16-pin thin QFN with exposed pad (EP), RoHS-compliant, thermal performance optimized for PCB copper pour attachment.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power-supply supervisory applications.

Compared with MAX6887QETE+, the MAX6888QETE+ reduces pin count and simplifies routing for four-rail systems, while retaining identical accuracy, timing, and interface behavior; versus TPS3808G33DBVR, it delivers integrated quad monitoring, overvoltage protection, and watchdog supervision in one device - eliminating multiple discrete supervisors and interconnect complexity.

Availability

MAX6888QETE+ is available at Aetrix Electronics and suitable for telecom power shelves, server baseboard management, industrial PLC backplanes, and networking switch line cards requiring stable component supply and long-term lifecycle support.

Supply support for MAX6888QETE+ 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 MAX6887/MAX6888 product line delivers multirail power-supply supervision with integrated watchdog and margining control - engineered specifically for high-availability systems where coordinated fault detection and recovery are critical.

FAQ

What is the undervoltage threshold configuration for MAX6888QETE+?

The MAX6888QETE+ has factory-set undervoltage thresholds of 0.557V (±1%) on all four inputs (IN1–IN4), intended for use with external resistor dividers to monitor higher supply voltages. This configuration is confirmed in Table 2 of the datasheet and applies exclusively to the "Q" variant, which uses the 5% tolerance option with adjustable nominal voltages.

Can MAX6888QETE+ be powered from a single 3.3V supply?

Yes - MAX6888QETE+ can be powered from any one of IN1–IN4 or VCC, provided the selected supply is ≥2.7V. When using a 3.3V rail, connect it to IN1 (or any INx), and ensure the 1µF ceramic bypass capacitor is placed directly between VCC and GND. The device's virtual diode-ORing selects the highest valid input to power internal circuitry.

How does the MARGIN pin affect RESET behavior in MAX6888QETE+?

When the MARGIN pin is pulled low, MAX6888QETE+ holds RESET, OV, and WDO in their current asserted or deasserted states regardless of subsequent changes on IN1–IN4 or WDI activity. This enables controlled system stress testing. MARGIN overrides MR if both are asserted, and it is internally pulled up to BP via a 10µA current source when left unconnected.

What is the watchdog timeout sequence after power-up for MAX6888QETE+?

At power-up, MAX6888QETE+ enters an initial watchdog timeout period of 102.4s (tWDI). After WDO goes high, the first WDI transition starts the normal 1.6s timeout (tWD). If no further WDI toggles occur within that interval, WDO asserts low. Connecting WDO to MR causes a ~5µs RESET pulse, clearing the watchdog and restarting the cycle.

Does MAX6888QETE+ require external pull-up resistors on its outputs?

Yes - all three outputs (RESET, OV, WDO) are active-low open-drain and require external pull-up resistors to the appropriate logic rail (e.g., 3.3V or 5V). Typical values range from 4.7kΩ to 10kΩ. The datasheet specifies VOL ≤ 0.4V at 4mA sink, confirming compatibility with standard CMOS input thresholds when properly terminated.