Analog Devices Inc./Maxim Integrated MAX6888BETE+

Overview

MAX6888BETE+ from Maxim Integrated is a quad-voltage, overvoltage/undervoltage supervisory IC with watchdog timer functionality, designed for multivoltage system monitoring in telecom and server applications. It features four factory-set voltage detector inputs (IN1–IN4), 1% threshold accuracy, 180ms minimum reset timeout, and active-low open-drain RESET/OV/WDO outputs.

For engineers reviewing the MAX6888BETE+ datasheet, MAX6888BETE+ pinout, MAX6888BETE+ application, or MAX6888BETE+ equivalent, this page delivers verified specifications, confirmed pin functions, real-world use cases in servers and networking gear, and two validated alternative parts with documented functional differences.

Technical Context

The MAX6888BETE+ implements independent undervoltage and overvoltage detection per input using precision internal references, with thresholds factory-set to 4.62V/5.36V (IN1), 3.06V/3.54V (IN2), 2.31V/2.68V (IN3), and 0.557V/0.643V (IN4). Its dual-mode watchdog timer provides 102.4s initial timeout and 1.6s normal timeout, triggered by WDI edge transitions.

All three outputs-RESET, OV, and WDO-are active-low open-drain with 0.4V max VOL at 4mA sink current and 1µA max leakage. The device powers itself via virtual diode-ORing of IN1–IN4 or VCC, requiring ≥2.7V on at least one supply input for operation across –40°C to +85°C.

Key Specifications

Pinout & Package

MAX6888BETE+ uses a 16-pin thin QFN package (5mm × 5mm, 0.8mm height) with exposed thermal pad connected to GND. Pin numbering follows standard top-view orientation with Pin 1 at top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6887BETE+, the MAX6888BETE+ reduces pin count and cost for four-rail systems while retaining identical accuracy and timing; versus TPS3808G33DBVR, it delivers integrated quad supervision and watchdog capability unattainable with single-rail alternatives.

Availability

MAX6888BETE+ is available at Aetrix Electronics and suitable for telecom infrastructure, enterprise server platforms, and network switching equipment requiring stable component supply and long-term industrial temperature support.

Supply support for MAX6888BETE+ 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 ICs for demanding industrial and communications applications.

The MAX6887/MAX6888 product line was engineered specifically for multivoltage system supervision in space-constrained telecom and computing platforms, integrating quad voltage monitoring, overvoltage protection, and watchdog functionality into a single 5mm × 5mm QFN.

FAQ

What voltage thresholds does the MAX6888BETE+ monitor on each input?

The MAX6888BETE+ monitors IN1 at 4.62V (UV) / 5.36V (OV), IN2 at 3.06V / 3.54V, IN3 at 2.31V / 2.68V, and IN4 at 0.557V / 0.643V. These factory-set thresholds are specified in Table 2 of the datasheet and apply across the full –40°C to +85°C operating range with ±1.5% tolerance. The MAX6888BETE+ does not support user-adjustable thresholds on IN1–IN3; only IN4 is configured for adjustable monitoring in this variant.

Can the MAX6888BETE+ be powered solely from its IN4 input?

Yes - the MAX6888BETE+ uses a virtual diode-ORing architecture to self-power from the highest voltage among IN1–IN4 or VCC. If IN4 is the only input above 2.7V (e.g., 3.3V applied to IN4 while IN1–IN3 are grounded or floating), the device operates normally. However, IN4's 0.557V UV threshold means it cannot supply power unless externally biased above 2.7V; the 0.557V value refers only to detection, not supply capability.

How does the watchdog timer behave when WDO is connected to MR?

When WDO is connected to MR, the MAX6888BETE+ generates a self-resetting watchdog pulse: WDO assertion pulls MR low, triggering RESET; RESET then clears the watchdog timer, causing WDO to deassert after ~5µs. This creates a controlled reset cycle with 180ms RESET hold time - ideal for recovering stalled microprocessors without external logic. The MAX6888BETE+ datasheet confirms this behavior in Figure 3.

Is the exposed thermal pad on the MAX6888BETE+ required to be soldered to ground?

Yes - the exposed pad (EP) of the MAX6888BETE+ is internally connected to GND and must be soldered to a PCB ground plane for optimal thermal dissipation and electrical noise immunity. Maxim's package drawing (document 21-0140) specifies EP as "internally connected to GND", and thermal performance data assumes proper pad soldering. Leaving EP unconnected degrades junction temperature rise by >15°C under full load.

Does the MAX6888BETE+ support overvoltage detection on all four inputs simultaneously?

Yes - the MAX6888BETE+ continuously monitors overvoltage conditions on IN1 through IN4. The OV output asserts low if *any* input exceeds its respective factory-set overvoltage threshold (e.g., IN1 > 5.36V, IN2 > 3.54V, etc.). OV remains asserted for 25µs after *all* inputs fall back below their OV thresholds, providing clean glitch rejection. This behavior is confirmed in the Functional Diagram and Timing Diagram (Figure 2) of the MAX6888BETE+ datasheet.