Analog Devices Inc./Maxim Integrated MAX6385XS43D4-T

Overview

MAX6385XS43D4-T from Maxim Integrated is a push-pull active-high microprocessor supervisory circuit with factory-set 4.30V reset threshold, 1120ms V_CC reset timeout, and manual reset input. It monitors single-supply voltages from +1.8V to +5.0V, consumes only 3μA at +1.8V, guarantees valid reset output down to V_CC = 1V, and operates across -40°C to +125°C for industrial and automotive power-up/brownout protection in embedded controllers.

For engineers reviewing the MAX6385XS43D4-T datasheet, MAX6385XS43D4-T pinout, MAX6385XS43D4-T application, or MAX6385XS43D4-T equivalent, key selection criteria include its 4.30V ±2.5% threshold accuracy over temperature, 1120ms/140ms dual timeout configuration, SC70-4 package footprint, MR debounced input with internal 63kΩ pullup, and guaranteed push-pull active-high reset assertion during low-V_CC conditions.

Technical Context

The MAX6385XS43D4-T implements a precision bandgap-based voltage comparator monitoring V_CC against a fixed 4.30V threshold, with ±2.5% tolerance over -40°C to +125°C and 60ppm/°C tempco. Its internal timer asserts RESET high for ≥1120ms after V_CC rises above threshold, and ≥140ms after MR release.

It features a dedicated active-low manual reset input (MR) with internal 63kΩ pullup, TTL/CMOS-compatible logic levels, 1µs minimum pulse width, and 100ns glitch rejection. The push-pull active-high RESET output drives up to 800µA source / 3.2mA sink while maintaining valid logic states down to V_CC = 1V.

Key Specifications

Pinout & Package

MAX6385XS43D4-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 0.65mm pin pitch and 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 MAX6385XS43D4-T, MAX6385XS43D3-T offers faster reset release but less margin for slow-rising rails, while TPS3808G33DBVR targets lower-voltage systems without manual reset capability - neither is pin-compatible, and both require schematic and layout changes.

Availability

MAX6385XS43D4-T is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, medical infusion pumps, and smart energy meters requiring stable component supply with guaranteed automotive-grade (-40°C to +125°C) performance and RoHS compliance.

Supply support for MAX6385XS43D4-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.

The MAX6381–MAX6390 family delivers ultra-low-power, high-accuracy reset supervision for microprocessor-based systems operating under wide voltage and temperature ranges - specifically engineered for reliability-critical power monitoring in harsh environments.

FAQ

What is the exact reset threshold voltage of MAX6385XS43D4-T and how accurate is it over temperature?

The MAX6385XS43D4-T has a factory-set nominal reset threshold of 4.30V, 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, where V_TH min/max values are listed as 4.19V/4.41V at +25°C and maintain ±2.5% tolerance across temperature. The MAX6385XS43D4-T achieves this stability via laser-trimmed bandgap reference and low-tempco design.

Does MAX6385XS43D4-T support manual reset, and what are the electrical requirements for the MR pin?

Yes, MAX6385XS43D4-T includes a debounced manual reset input (MR) with an internal 63kΩ pullup resistor to V_CC. The MR pin is active-low and accepts TTL/CMOS logic levels: V_IL ≤ 0.3×V_CC (for V_TH < 4V) and V_IH ≥ 0.7×V_CC. It requires a minimum pulse width of 1µs and rejects glitches ≤100ns. No external components are needed - a momentary switch from MR to GND suffices. This functionality is explicitly documented for MAX6385 in the Pin Description and Features sections of the MAX6381–MAX6390 datasheet.

What is the reset timeout behavior of MAX6385XS43D4-T during power-up versus manual reset?

The MAX6385XS43D4-T provides two distinct timeout periods: a 1120ms minimum V_CC reset timeout activated when V_CC rises above 4.30V, and a separate 140ms minimum manual reset timeout triggered upon MR release. This dual-timing architecture ensures sufficient hold time for power rail stabilization during startup while enabling rapid, controlled resets during field service. Both timeouts are guaranteed minimum values per the Reset Timeout Period table in the datasheet, and the MAX6385XS43D4-T implements them using independent internal timers.

Can MAX6385XS43D4-T operate reliably at very low supply voltages, and what is its minimum functional V_CC?

Yes, MAX6385XS43D4-T guarantees correct reset output logic state down to V_CC = 1.0V, as stated in the Absolute Maximum Ratings and Detailed Description sections. Its push-pull active-high RESET output remains valid (i.e., correctly asserted or deasserted) across the full 1.0V to 5.5V operating range. This capability ensures deterministic behavior during deep brownout conditions where other supervisors may release reset prematurely. The MAX6385XS43D4-T achieves this via specialized low-voltage biasing and comparator design, verified across temperature.

What package type and footprint does MAX6385XS43D4-T use, and are land patterns available?

MAX6385XS43D4-T is supplied in a 4-pin SC70 package (package code X4+1, outline 21-0098), with dimensions 2.0mm × 2.1mm × 0.95mm and 0.65mm pin pitch. Official land pattern number 90-0187 is published by Maxim Integrated and available at maximintegrated.com/packages. The SC70-4 footprint is compact and reflow-compatible, supporting high-density PCB layouts. This package assignment is confirmed in the Ordering Information table, where MAX6385XS_ _D_+T entries specify "4 SC70" under PIN-PACKAGE.