Analog Devices Inc./Maxim Integrated MAX6385XS44D3-T

Overview

MAX6385XS44D3-T from Maxim Integrated is a low-power microprocessor supervisory circuit with active-high push-pull reset output, factory-set 4.38V reset threshold (±2.5% over -40°C to +125°C), 140ms minimum VCC reset timeout, and integrated debounced manual reset input. It monitors single supply voltage in battery-powered controllers and portable instrumentation where reliable power-on reset and brownout protection are critical.

For engineers reviewing the MAX6385XS44D3-T datasheet, MAX6385XS44D3-T pinout, MAX6385XS44D3-T application, or MAX6385XS44D3-T equivalent, key selection criteria include reset threshold accuracy at temperature extremes, guaranteed reset validity down to VCC = 1V, manual reset timing behavior, SC70-4 package footprint compatibility, and RoHS-compliant lead-free construction.

Technical Context

The MAX6385XS44D3-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 guarantees a minimum 140ms reset assertion after VCC rises above 4.38V, with reset deassertion occurring only after timeout completion.

This device features an active-high push-pull RESET output capable of sourcing 800µA at VCC ≥ 4.5V (VOH ≥ 0.8×VCC) and sinking 3.2mA (VOL ≤ 0.4V), plus a debounced MR input with 63kΩ internal pullup resistor-enabling direct connection to momentary switches without external RC networks.

Key Specifications

Pinout & Package

MAX6385XS44D3-T is housed in a 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm with 0.65mm pitch. This RoHS-compliant, lead-free surface-mount package supports high-density PCB layouts and reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS44D3-T, the MAX6385XS44D2-T reduces boot delay for time-critical applications, while the MAX6326XR44D3-T sacrifices MR functionality and output drive strength to meet legacy open-drain interface requirements - neither offers pin-compatible replacement without layout or firmware changes.

Availability

MAX6385XS44D3-T is available at Aetrix Electronics and suitable for portable medical instrumentation, battery-powered industrial controllers, automotive body control modules, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6385XS44D3-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 applications, with emphasis on power efficiency and reliability.

The MAX6381–MAX6390 family delivers ultra-low-power, factory-trimmed supervisory circuits optimized for space-constrained, battery-operated, and high-temperature embedded systems requiring deterministic reset behavior.

FAQ

What is the exact reset threshold voltage of MAX6385XS44D3-T and how tightly is it specified?

The MAX6385XS44D3-T has a nominal reset threshold of 4.38V, with a guaranteed range of 4.27V to 4.48V at +25°C and ±2.5% accuracy maintained over the full -40°C to +125°C operating temperature range. This specification is factory-trimmed and does not require external calibration - the "44" suffix in MAX6385XS44D3-T explicitly denotes this 4.38V threshold point per Maxim's ordering guide.

Does MAX6385XS44D3-T support manual reset, and what are the electrical characteristics of its MR input?

Yes, MAX6385XS44D3-T includes a debounced manual reset (MR) input with a 63kΩ internal pullup resistor to VCC. The MR pin accepts TTL- or CMOS-compatible logic levels, requires a minimum 1µs low pulse width, and rejects glitches shorter than 100ns. When pulled low, MR forces immediate reset assertion and holds it for the full 140ms timeout after release - enabling robust front-panel or test-point reset functionality without external components.

What is the reset output configuration of MAX6385XS44D3-T, and how does it interface with common microcontrollers?

MAX6385XS44D3-T features an active-high push-pull RESET output, meaning it drives high during reset assertion and low when released. This configuration directly interfaces with microcontrollers requiring active-high reset signals (e.g., many ARM Cortex-M series), eliminating the need for external pullup resistors or level-shifting circuitry. The output can source up to 800µA at VCC ≥ 4.5V and sink up to 3.2mA, ensuring reliable drive into typical µP reset input capacitance and leakage.

Can MAX6385XS44D3-T operate reliably during severe brownout conditions, and down to what VCC level does it guarantee correct reset behavior?

MAX6385XS44D3-T guarantees valid reset output state down to VCC = 1.0V, ensuring deterministic behavior even during deep brownout events. Its internal circuitry remains functional and the RESET output retains correct logic polarity throughout this range - a critical feature for fail-safe operation in battery-powered systems where supply voltage may sag below nominal levels before complete shutdown.

What package type and footprint does MAX6385XS44D3-T use, and are there thermal or layout considerations?

MAX6385XS44D3-T uses a 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm with 0.65mm pin pitch. Its junction-to-ambient thermal resistance is 322.6°C/W on a multilayer board. For optimal performance, place a 0.1µF ceramic capacitor between VCC and GND as close as possible to the device pins to suppress high-frequency noise and improve transient immunity - especially important in noisy industrial or automotive environments.