Analog Devices Inc./Maxim Integrated MAX6388XS27D4-T

Overview

The MAX6388XS27D4-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), 1120ms minimum VCC reset timeout, and auxiliary RESET IN input for dual-voltage monitoring. It operates from 1.0V to 5.5V supply, consumes only 3μA at 1.8V, and guarantees valid reset state down to VCC = 1V - ideal for battery-powered embedded controllers requiring reliable brownout protection.

For engineers reviewing the MAX6388XS27D4-T datasheet, MAX6388XS27D4-T pinout, MAX6388XS27D4-T application, or MAX6388XS27D4-T equivalent, key selection criteria include its 2.70V reset threshold accuracy, 1120ms timeout timing, 4-pin SC70 package footprint, auxiliary voltage monitoring capability, and compatibility with dual-rail power systems where core and I/O supplies must be independently validated.

Technical Context

This device integrates a precision bandgap reference, comparator-based VCC monitor, auxiliary RESET IN comparator referenced to 1.27V ±2.5%, and a digitally controlled timeout timer. Its reset assertion logic responds to either VCC falling below 2.70V or RESET IN falling below 1.27V, with independent glitch rejection (100ns) on both inputs.

The active-high push-pull RESET output drives high during fault conditions and deasserts cleanly after the 1120ms timeout; the internal 4-pin SC70 layout isolates GND and VCC pins for stable operation in noisy environments, and the RESET IN input draws only ±1nA leakage current, enabling high-impedance resistor-divider threshold setting without loading error.

Key Specifications

Pinout & Package

MAX6388XS27D4-T is housed in a RoHS-compliant 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm, 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 MAX6388XS27D4-T, the μDFN variant offers superior thermal management but increases PCB area by 140%, while TLV809E27DBZR reduces supply current by 40% but sacrifices dual-supply capability and timeout duration - making MAX6388XS27D4-T optimal for space-constrained dual-rail systems needing robust 1120ms reset hold.

Availability

MAX6388XS27D4-T is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, portable medical devices, smart energy meters, and dual-voltage embedded systems requiring stable component supply with guaranteed long-term availability.

Supply support for MAX6388XS27D4-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, communications, and computing markets, emphasizing low power, high reliability, and AEC-Q100 qualification.

The MAX6381–MAX6390 family delivers single/dual low-voltage microprocessor supervisory circuits optimized for battery-powered and harsh-environment applications where accurate, low-current reset generation is critical.

FAQ

What is the exact reset threshold voltage of MAX6388XS27D4-T and how stable is it over temperature?

The MAX6388XS27D4-T has a factory-set VCC reset threshold of 2.70V nominal, with ±2.5% tolerance guaranteed over the full -40°C to +125°C operating range. This stability is achieved via laser-trimmed bandgap reference and comparator design, and the datasheet confirms 60ppm/°C tempco - meaning threshold drift is less than ±13.5mV across the entire temperature span. The MAX6388XS27D4-T maintains this accuracy without external calibration.

Does MAX6388XS27D4-T support monitoring two independent power rails simultaneously?

Yes, the MAX6388XS27D4-T supports dual-rail supervision: its primary VCC pin monitors the main supply (e.g., 3.3V), while the dedicated RESET IN pin compares an external voltage against an internal 1.27V reference. By connecting a resistor divider to RESET IN, users can set a second threshold - for example, configuring it to assert reset if a 1.2V core rail drops below specification. This eliminates the need for a second supervisor IC in the MAX6388XS27D4-T design.

What is the function of the RESET output on MAX6388XS27D4-T and how does it behave during power failure?

The RESET output of the MAX6388XS27D4-T is an active-high push-pull driver. During normal operation (VCC ≥ 2.70V and RESET IN ≥ 1.27V), RESET remains low. When either voltage falls below its threshold, RESET immediately drives high and stays high for the full 1120ms timeout period after both voltages recover. This behavior ensures the connected microprocessor remains held in reset long enough to complete safe shutdown or restart - a key feature of the MAX6388XS27D4-T.

Can MAX6388XS27D4-T operate reliably at very low supply voltages, and what is its minimum functional VCC?

Yes, the MAX6388XS27D4-T is guaranteed to produce a valid RESET output down to VCC = 1.0V, as confirmed in the Absolute Maximum Ratings and Electrical Characteristics tables. Below 1.0V, the internal circuitry may not sustain correct logic states - however, at 1.0V the device still asserts or deasserts RESET with defined timing and voltage levels. This extended low-VCC operation makes the MAX6388XS27D4-T suitable for brownout recovery in deeply discharged battery systems.

What package type and footprint does MAX6388XS27D4-T use, and are there alternative packages available?

The MAX6388XS27D4-T uses a 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm. An alternative μDFN version - MAX6388LT27D4-T - is available in a 6-pin μDFN (L611+1, outline 21-0147, land pattern 90-0080). Both share identical electrical specifications, but the μDFN offers better thermal performance (θ_JA = 477°C/W vs. 322.6°C/W) at the cost of larger PCB area. The MAX6388XS27D4-T is optimized for space-constrained designs.