Analog Devices Inc./Maxim Integrated MAX6388XS21D5-T

Overview

MAX6388XS21D5-T from Maxim Integrated is a low-power microprocessor supervisory circuit with active-high push-pull reset output, factory-set 2.10V VCC reset threshold (±2.5% over -40°C to +125°C), 280ms minimum reset timeout, and auxiliary RESET IN input for dual-voltage monitoring. It operates from 1.0V to 5.5V supply and consumes only 3μA at 1.8V, targeting power-critical embedded systems requiring reliable brownout detection.

For engineers reviewing the MAX6388XS21D5-T datasheet, MAX6388XS21D5-T pinout, MAX6388XS21D5-T application, or MAX6388XS21D5-T equivalent, key selection criteria include its 2.10V reset threshold accuracy, 280ms VCC timeout, dual-supply monitoring capability via RESET IN, and guaranteed valid reset output down to VCC = 1V - critical for battery-powered and automotive-grade designs.

Technical Context

The MAX6388XS21D5-T integrates a precision voltage comparator for VCC monitoring against a fixed 2.10V threshold and a separate high-impedance RESET IN comparator referenced to +1.27V, enabling user-defined secondary voltage supervision via external resistor divider. Its internal timer ensures reset assertion for ≥280ms after VCC or RESET IN recovers above their respective thresholds.

It features an active-high push-pull RESET output that transitions high during fault conditions (VCC < 2.10V or RESET IN < 1.27V) and remains asserted for the full timeout period. The device guarantees correct logic state of RESET down to VCC = 1V and provides immunity to negative-going VCC transients up to 100µs at 100mV overdrive.

Key Specifications

Pinout & Package

MAX6388XS21D5-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, suitable for space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6387XS21D5-T, MAX6388XS21D5-T eliminates external pullup components and simplifies layout; compared with TLV803EB21DBZR, it adds dual-supply monitoring without increasing quiescent current - making it optimal for compact, multi-rail, battery-sensitive designs.

Availability

MAX6388XS21D5-T is available at Aetrix Electronics and suitable for battery-powered instrumentation, automotive body control modules, industrial PLC I/O, medical wearable sensor hubs, and dual-voltage embedded systems requiring stable component supply and long-term lifecycle support.

Supply support for MAX6388XS21D5-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, mixed-signal, and power management ICs for demanding industrial, automotive, and computing applications.

The MAX6381–MAX6390 family delivers ultra-low-power, high-accuracy μP reset supervision with flexible reset polarity, timeout options, and dual-supply monitoring - engineered for reliability in harsh environments and energy-constrained devices.

FAQ

What is the reset threshold voltage of the MAX6388XS21D5-T?

The MAX6388XS21D5-T has a factory-set VCC reset threshold of 2.10V, specified with ±2.5% accuracy over the full operating temperature range of -40°C to +125°C. This value is confirmed in the Reset Thresholds table of the datasheet and applies specifically to the "21" suffix in the part number. The MAX6388XS21D5-T uses this threshold to detect brownout conditions on the main supply rail.

Does the MAX6388XS21D5-T support monitoring of a second voltage rail?

Yes, the MAX6388XS21D5-T includes a dedicated RESET IN terminal that connects to an internal +1.27V reference comparator. By applying a resistor divider to RESET IN, users can set a custom threshold for a secondary voltage rail - for example, configuring a 3.3V rail to trigger reset when it falls below 3.3V. This dual-monitoring capability is explicitly documented for MAX6387/MAX6388/MAX6389 variants in the Pin Description and Applications Information sections.

What is the function of the RESET output on the MAX6388XS21D5-T?

The RESET output of the MAX6388XS21D5-T is an active-high push-pull driver. It asserts high when VCC falls below 2.10V or when the voltage at RESET IN drops below +1.27V, and remains high for a minimum of 280ms after recovery. Unlike open-drain alternatives, this output requires no external pullup resistor and directly interfaces with standard μP reset inputs. Its guaranteed validity down to VCC = 1V ensures deterministic behavior during deep undervoltage events.

What package type and pin count does the MAX6388XS21D5-T use?

The MAX6388XS21D5-T is packaged in a 4-pin SC70 (surface-mount) outline, identified as package code X4+1 with outline number 21-0098 and land pattern 90-0187. It measures 2.0mm × 2.1mm × 0.95mm and contains four terminals: VCC, RESET, GND, and RESET IN. This matches the ordering information table specifying "MAX6388XS_ _D_+T" for 4-pin SC70 variants.

How much supply current does the MAX6388XS21D5-T consume at low voltage?

The MAX6388XS21D5-T consumes only 3μA of supply current at VCC = +1.8V and room temperature, as specified in the Electrical Characteristics table. At +3.6V, consumption rises to 6μA (typical). This ultra-low quiescent current enables multi-year operation in battery-powered applications such as portable test equipment and medical wearables, and is a defining feature of the MAX6381–MAX6390 family.