Analog Devices Inc./Maxim Integrated MAX6385XS31D3+T

Overview

MAX6385XS31D3+T from Maxim Integrated is a low-power microprocessor supervisory circuit with active-high push-pull reset output, factory-set 3.08V reset threshold (±2.5% over –40°C to +125°C), and 140ms minimum VCC reset timeout. It monitors single supply voltage in portable/battery-powered equipment and embedded controllers, asserting reset during power-up, brownout, or manual trigger events.

For engineers reviewing the MAX6385XS31D3+T datasheet, MAX6385XS31D3+T pinout, MAX6385XS31D3+T application, or MAX6385XS31D3+T equivalent, key selection criteria include guaranteed reset validity down to VCC = 1V, 3μA supply current at 1.8V, manual reset input with internal 63kΩ pullup, and 4-pin SC70 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6385XS31D3+T implements a precision bandgap-based reset comparator with ±2.5% threshold accuracy across –40°C to +125°C and 60ppm/°C tempco. Its internal timer enforces a fixed 140ms minimum reset assertion period after VCC rises above 3.08V or after MR release.

It features a debounced active-low manual reset input (MR) with 1µs minimum pulse width support and 100ns glitch rejection, and guarantees correct reset output logic state for VCC ≥ 1V - critical for low-voltage brownout detection in battery-operated systems.

Key Specifications

Pinout & Package

MAX6385XS31D3+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 - optimized for ultra-compact portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS31D3+T, the /V variant adds automotive qualification without altering functionality, while TPS3808G33DBVR trades MR capability and compact SC70 size for lower ICC and higher threshold precision - making it suitable for fixed-threshold, no-manual-reset applications where board space is less constrained.

Availability

MAX6385XS31D3+T is available at Aetrix Electronics and suitable for portable/battery-powered equipment, industrial controller monitoring, and wearable sensor node designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6385XS31D3+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 power, sensing, and timing applications, with emphasis on low-power, high-reliability solutions for demanding environments.

The MAX6381–MAX6390 family delivers single/dual-supply microprocessor reset supervision with ultra-low ICC, factory-trimmed thresholds, and multiple reset output configurations - engineered for battery longevity and robust operation in portable, industrial, and automotive systems.

FAQ

What is the exact reset threshold voltage of MAX6385XS31D3+T and how is it specified?

The MAX6385XS31D3+T has a nominal reset threshold of 3.08V, defined by the "31" suffix per Maxim's ordering guide. This value is factory-trimmed with ±2.5% accuracy over –40°C to +125°C and exhibits a 60ppm/°C tempco. The threshold is guaranteed not to drift outside VTH ±2.5% across temperature, ensuring consistent brownout detection in harsh environments without external calibration.

Does MAX6385XS31D3+T support manual reset, and what are its interface requirements?

Yes, MAX6385XS31D3+T includes an active-low manual reset input (MR) with an internal 63kΩ pullup resistor to VCC. It accepts TTL- or CMOS-compatible logic levels: VIH ≥ 0.7×VCC and VIL ≤ 0.3×VCC for VTH < 4V. A momentary switch from MR to GND suffices for manual reset; no external debounce components are needed due to built-in 100ns glitch rejection and 1µs minimum pulse width support.

What package type and dimensions does MAX6385XS31D3+T use, and is it RoHS-compliant?

MAX6385XS31D3+T uses a 4-pin SC70 package (outline 21-0098), measuring 2.0mm × 2.1mm × 0.95mm with 0.65mm pin pitch. The "+T" suffix confirms lead(Pb)-free and RoHS-compliant construction. This ultra-compact footprint enables high-density PCB layouts in space-constrained applications like wearables and handheld instruments.

How does MAX6385XS31D3+T behave during deep brownout conditions near 1V supply?

MAX6385XS31D3+T guarantees correct reset output logic state down to VCC = 1V - meaning the active-high RESET pin remains valid (driving high during reset, low otherwise) even as supply collapses. This ensures deterministic MCU behavior during severe undervoltage events, unlike many supervisors that lose output control below 1.5V. No external pulldown resistor is required for push-pull operation.

What is the minimum reset timeout period of MAX6385XS31D3+T, and how is it implemented?

The MAX6385XS31D3+T provides a minimum reset timeout period of 140ms (suffix "D3"), enforced by an internal monolithic timer. After VCC rises above 3.08V or MR is released, the active-high RESET output remains asserted for at least 140ms - independent of temperature, supply voltage, or process variation. This ensures sufficient time for power rails and clocks to stabilize before MCU firmware execution resumes.