Analog Devices Inc./Maxim Integrated MAX6388XS27D7-T

Overview

The MAX6388XS27D7-T from Maxim Integrated is a low-power microprocessor supervisory circuit with active-high push-pull reset output, factory-set 2.70V VCC reset threshold (±2.5% over −40°C to +125°C), 1200ms minimum VCC reset timeout, and auxiliary RESET IN input for dual-voltage monitoring. It consumes only 3μA at +1.8V and guarantees valid reset state down to VCC = 1V, used in battery-powered controllers and dual-rail embedded systems.

For engineers reviewing the MAX6388XS27D7-T datasheet, MAX6388XS27D7-T pinout, MAX6388XS27D7-T application, or MAX6388XS27D7-T equivalent, key selection criteria include its 2.70V threshold accuracy, 1200ms VCC timeout, 4-pin SC70 package, RESET IN comparator interface, and compatibility with dual-supply brownout detection in space-constrained industrial controllers.

Technical Context

The MAX6388XS27D7-T integrates a precision bandgap reference and comparator to monitor VCC against a fixed 2.70V threshold while simultaneously accepting an external voltage via RESET IN, which is compared to an internal +1.27V reference. Its reset assertion logic triggers on either VCC < 2.70V or RESET IN < 1.27V.

It features a digitally controlled timeout timer that holds the active-high RESET output asserted for ≥1200ms after VCC recovers above threshold, and includes built-in immunity to negative-going VCC transients up to 150µs (at 100mV overdrive), verified across −40°C to +125°C.

Key Specifications

Pinout & Package

MAX6388XS27D7-T is housed in a RoHS-compliant 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 1.0mm × 1.0mm × 0.5mm, with thermal resistance θ_JA = 322.6°C/W on multilayer board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor reset applications.

Compared with MAX6388LT27D7-T, the MAX6388XS27D7-T saves 60% board area but trades 155°C/W higher junction-to-ambient thermal resistance; versus TPS3808G33DBVR, it provides critical dual-voltage supervision and 6× longer reset timeout - essential for complex SoC initialization.

Availability

MAX6388XS27D7-T is available at Aetrix Electronics and suitable for battery-powered instrumentation, dual-voltage microcontroller systems, and automotive body control modules requiring stable component supply with guaranteed long-term availability.

Supply support for MAX6388XS27D7-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 industrial, automotive, and computing applications, with emphasis on low-power, high-reliability solutions.

The MAX6381–MAX6390 family delivers single/dual low-voltage μP reset circuits optimized for space-constrained, battery-sensitive systems requiring guaranteed reset behavior across extreme temperatures and supply transients.

FAQ

What is the exact reset threshold voltage of the MAX6388XS27D7-T and how stable is it over temperature?

The MAX6388XS27D7-T has a factory-set VCC reset threshold of 2.70V nominal, with ±2.5% accuracy guaranteed over the full operating temperature range of −40°C to +125°C. This stability is achieved through laser-trimmed bandgap references and matched comparator design, ensuring consistent brownout detection without system-level calibration. The MAX6388XS27D7-T maintains this specification under all load conditions and supply voltages from 1.0V to 5.5V.

Does the MAX6388XS27D7-T support monitoring of a second voltage rail, and how is it implemented?

Yes, the MAX6388XS27D7-T supports dual-voltage monitoring via its dedicated RESET IN pin, which compares an external voltage to an internal +1.27V reference. To monitor a second rail (e.g., 3.3V or 5.0V), connect a resistor divider between that rail and GND, feeding the midpoint to RESET IN. The MAX6388XS27D7-T asserts reset if either VCC falls below 2.70V or the divided voltage drops below 1.27V - enabling true independent supervision of two supplies.

What is the function of the RESET output on the MAX6388XS27D7-T, and what drive strength does it provide?

The RESET output of the MAX6388XS27D7-T is an active-high push-pull driver, meaning it actively drives high during reset assertion and actively pulls low when deasserted - no external pullup resistor is needed. At VCC ≥ 1.0V, it sources ≥80µA while maintaining VOH ≥ 0.8×VCC, and sinks ≥80µA while maintaining VOL ≤ 0.3V. This ensures robust interfacing with standard CMOS microprocessor reset inputs across its full 1.0V–5.5V operating range.

How does the MAX6388XS27D7-T handle short-duration power supply transients?

The MAX6388XS27D7-T incorporates inherent immunity to negative-going VCC transients: it will not assert reset for glitches ≤150µs wide when the overdrive (VTH − VCC) is 100mV, as characterized in the "Maximum Transient Duration vs. Reset Comparator Overdrive" graph. This rejection is achieved through internal filtering and comparator hysteresis. For enhanced immunity, a 0.1µF ceramic capacitor placed close to the VCC pin further suppresses high-frequency noise, making the MAX6388XS27D7-T suitable for motor-drive and switching-power-supply environments.

What package type and dimensions does the MAX6388XS27D7-T use, and are there thermal considerations?

The MAX6388XS27D7-T uses a 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 1.0mm × 1.0mm × 0.5mm with 0.65mm pin pitch. Its junction-to-ambient thermal resistance (θ_JA) is 322.6°C/W on a multilayer PCB. While adequate for typical low-power applications, designers should verify temperature rise under worst-case ambient + self-heating conditions - especially in sealed enclosures - since the MAX6388XS27D7-T operates up to +125°C and its threshold accuracy is specified across that full range.