Analog Devices Inc./Maxim Integrated MAX6385XS31D4-T

Overview

MAX6385XS31D4-T from Maxim Integrated is a precision microprocessor supervisory circuit with active-high push-pull reset output, factory-set 3.08V reset threshold (±2.5% over –40°C to +125°C), 1120ms minimum VCC reset timeout, and debounced manual reset input. It monitors single-supply rails in low-power embedded systems where reliable power-on reset and brownout protection are critical, such as battery-powered IoT sensors and industrial controllers.

For engineers reviewing the MAX6385XS31D4-T datasheet, MAX6385XS31D4-T pinout, MAX6385XS31D4-T application, or MAX6385XS31D4-T equivalent, key selection criteria include its 3.08V threshold accuracy, 1120ms reset hold time, 4-pin SC70 package footprint, and guaranteed valid reset assertion down to VCC = 1V - all essential for deterministic μP initialization in space-constrained, wide-temperature designs.

Technical Context

This device implements a precision bandgap-based voltage comparator with ±2.5% threshold tolerance across –40°C to +125°C and a monotonic internal timer that guarantees ≥1120ms reset assertion after VCC recovers above 3.08V. Its MR input features a 63kΩ internal pullup and 1µs minimum pulse width requirement.

The active-high push-pull RESET output drives high during reset assertion and guarantees logic-valid state down to VCC = 1V; it sources up to 800µA at VCC ≥ 4.5V and sinks 3.2mA while asserted. No external pullup is required, distinguishing it from open-drain variants.

Key Specifications

Pinout & Package

MAX6385XS31D4-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 high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS31D4-T, the D3 variant offers faster reset release but less margin for slow-ramping supplies, while TPS3808G30DBVR trades manual reset and SC70 compatibility for improved threshold accuracy - making MAX6385XS31D4-T optimal for space-constrained, MR-requiring applications needing robust 1120ms hold time.

Availability

MAX6385XS31D4-T is available at Aetrix Electronics and suitable for industrial PLCs, battery-powered wireless sensors, automotive body control units, and medical portable diagnostics requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6385XS31D4-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 demanding industrial, automotive, and computing applications.

MAX6385XS31D4-T belongs to the MAX6381–MAX6390 family of low-power μP supervisors engineered for reliable power monitoring in space-constrained, wide-temperature embedded systems with strict quiescent current budgets.

FAQ

What is the exact reset threshold voltage of MAX6385XS31D4-T and how stable is it over temperature?

The MAX6385XS31D4-T has a factory-set nominal reset threshold of 3.08V, with guaranteed accuracy of ±2.5% over the full operating temperature range of –40°C to +125°C. This stability is achieved via laser-trimmed bandgap references and low-drift comparator design, ensuring consistent brownout detection without external calibration. The MAX6385XS31D4-T maintains this specification across its entire qualified temperature envelope.

Does MAX6385XS31D4-T require an external pullup resistor on its RESET output?

No, MAX6385XS31D4-T does not require an external pullup resistor because it features an active-high push-pull RESET output. The internal driver actively sources current when asserting reset (driving high) and sinks current when deasserting (driving low), eliminating dependency on external biasing. This simplifies layout and improves noise immunity compared to open-drain alternatives. The MAX6385XS31D4-T's push-pull architecture is confirmed in the device's pin description and electrical characteristics tables.

What is the minimum reset timeout period specified for MAX6385XS31D4-T, and how is it guaranteed?

The MAX6385XS31D4-T specifies a minimum VCC reset timeout period of 1120ms after VCC rises above the 3.08V threshold. This value is production-guaranteed per the datasheet's "Reset Timeout Period" table under the D4 suffix, with no upper limit specified - meaning actual timeout may exceed 1120ms but will never fall below it. The MAX6385XS31D4-T achieves this via a monotonic internal RC timer calibrated during wafer test.

Can MAX6385XS31D4-T monitor a second voltage rail, and what pins are involved?

No, MAX6385XS31D4-T cannot monitor a second voltage rail. It is a single-supply supervisor with only VCC monitoring capability. Devices supporting auxiliary voltage monitoring (e.g., RESET IN) belong to the MAX6387/MAX6388/MAX6389 variants and use a dedicated pin not present on the 4-pin SC70 package of MAX6385XS31D4-T. The MAX6385XS31D4-T pinout confirms only VCC, RESET, MR, and GND - no RESET IN function is implemented.

What package type and dimensions does MAX6385XS31D4-T use, and is it RoHS-compliant?

MAX6385XS31D4-T uses a 4-pin SC70 package (outline number 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm. It is RoHS-compliant and lead-free, indicated by the "+T" suffix in the ordering code. This compact footprint supports high-density PCB layouts in portable and automotive applications. The MAX6385XS31D4-T's package data is explicitly documented in the "Package Information" section of the official datasheet.