Analog Devices Inc./Maxim Integrated MAX6385XS46D3

Overview

MAX6385XS46D3 from Maxim Integrated is a low-power, active-high push-pull microprocessor supervisory circuit with factory-set 4.63V reset threshold, 140ms minimum reset timeout, and manual reset input. It monitors VCC in systems requiring precise brownout detection and reliable power-on reset for embedded controllers and battery-powered devices.

For engineers reviewing the MAX6385XS46D3 datasheet, MAX6385XS46D3 pinout, MAX6385XS46D3 application, or MAX6385XS46D3 equivalent, key selection criteria include its 4.63V ±2.5% threshold accuracy over –40°C to +125°C, 3µA supply current at 1.8V, guaranteed valid reset output down to VCC = 1V, and SC70-4 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6385XS46D3 implements a precision bandgap-based voltage comparator with internal 1.27V reference for threshold generation, paired with a temperature-stable RC timer for deterministic 140ms reset assertion after VCC recovery. Its active-high push-pull output drives directly into µP reset inputs without external pull-up components.

It integrates a debounced manual reset input (MR) with internal 63kΩ pullup resistor, enabling system-level reset initiation via momentary switch or logic signal. The device guarantees correct reset state down to VCC = 1V and exhibits immunity to negative-going VCC transients ≤140µs at 100mV overdrive.

Key Specifications

Pinout & Package

MAX6385XS46D3 is housed in a 4-pin SC70 package (package code X4-1), measuring 1.25mm × 1.0mm × 0.5mm, with gull-wing leads optimized for high-density PCB assembly and reflow compatibility.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS46D3, MAX809S omits manual reset and uses a smaller 3-pin package but lacks MR integration, while TPS3808G33 targets different voltage domains and introduces design complexity with external timing components - neither offers drop-in replacement capability for 4.63V/140ms/MR requirements.

Availability

MAX6385XS46D3 is available at Aetrix Electronics and suitable for industrial automation, automotive electronics, and portable medical devices requiring stable component supply, long-term lifecycle support, and lead-free compliance.

Supply support for MAX6385XS46D3 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 interface applications in demanding environments.

The MAX6381–MAX6390 family delivers single-supply, low-power µP supervisory circuits optimized for battery-operated, automotive, and industrial systems requiring high-accuracy voltage monitoring and robust reset timing.

FAQ

What is the exact reset threshold voltage of MAX6385XS46D3 and how tightly is it specified?

The MAX6385XS46D3 has a factory-set nominal reset threshold of 4.63V, with guaranteed accuracy of ±2.5% over the full operating temperature range of –40°C to +125°C. This specification is confirmed in the Electrical Characteristics table of the official datasheet and applies directly to the MAX6385XS46D3 variant, not the broader family. The threshold is trimmed during production using Maxim's precision bandgap reference architecture.

Does MAX6385XS46D3 support manual reset, and what is the internal pullup value on the MR pin?

Yes, MAX6385XS46D3 includes a debounced manual reset input (MR) with an internal 63kΩ pullup resistor to VCC, as explicitly stated in the Pin Description and Detailed Description sections. This allows direct connection of a momentary switch to GND without external components. The MR input accepts TTL/CMOS logic levels and features >100ns glitch rejection, making it suitable for noisy environments.

What package type and dimensions does MAX6385XS46D3 use, and is it RoHS-compliant?

MAX6385XS46D3 is packaged in a 4-pin SC70 (package code X4-1), measuring 1.25mm × 1.0mm × 0.5mm with gull-wing leads. The datasheet confirms this is a lead-free package (denoted by "+" in ordering suffix). Its small footprint and thermal profile are optimized for reflow soldering in high-density consumer and industrial PCBs.

How does the reset timeout of MAX6385XS46D3 behave across temperature and supply voltage?

The MAX6385XS46D3 guarantees a minimum reset timeout of 140ms, with typical variation less than ±5% across –40°C to +125°C and VCC = 1.8V to 5.5V, as shown in the Typical Operating Characteristics graph "Normalized Power-Up Reset Timeout vs. Temperature". This stability ensures consistent µP initialization timing regardless of environmental conditions or input voltage level.

Can MAX6385XS46D3 operate reliably during deep brownout conditions, and down to what VCC level does reset remain valid?

Yes, MAX6385XS46D3 guarantees correct reset output logic state down to VCC = 1.0V, as specified in the Absolute Maximum Ratings and Electrical Characteristics tables. This ensures fail-safe behavior during severe undervoltage events - for example, during battery depletion or sudden load transients - where many competing supervisors cease functioning above 1.5V.