Analog Devices Inc./Maxim Integrated MAX6385XS18D2-T

Overview

MAX6385XS18D2-T from Maxim Integrated is a push-pull active-high microprocessor supervisory circuit with factory-set 1.8V reset threshold, 20ms minimum reset timeout, and manual reset input (MR). It monitors VCC from +1.0V to +5.5V, consumes only 3μA at +1.8V, and guarantees valid reset output down to VCC = 1V. It is used in battery-powered embedded controllers requiring reliable power-on reset and brownout protection.

For engineers reviewing the MAX6385XS18D2-T datasheet, MAX6385XS18D2-T pinout, MAX6385XS18D2-T application, or MAX6385XS18D2-T equivalent, key selection criteria include its active-high push-pull output logic, MR debounce capability, ±2.5% reset threshold accuracy over –40°C to +125°C, and 4-pin SC70 package compatibility with space-constrained portable designs.

Technical Context

The MAX6385XS18D2-T implements a precision voltage comparator with internal 1.8V reference and an on-chip timer that asserts RESET for ≥20ms after VCC rises above threshold or after MR release. Its MR input features a 63kΩ internal pullup resistor and supports TTL/CMOS-compatible logic levels.

It operates across full industrial temperature range (–40°C to +125°C), maintains reset assertion during negative-going VCC transients up to 35µs (at 100mV overdrive), and ensures correct RESET state even as VCC drops to 1V - critical for graceful shutdown in low-power systems.

Key Specifications

Pinout & Package

MAX6385XS18D2-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 MAX6385XS18D2-T, MAX6385XS26D2-T shifts reset detection to higher voltage rails while preserving all other functionality, whereas TPS3123E18DBVR trades timing precision and package size for TI's process-specific reliability features - making MAX6385XS18D2-T optimal for tight-tolerance 1.8V core supervision in space-constrained designs.

Availability

MAX6385XS18D2-T is available at Aetrix Electronics and suitable for industrial PLC controllers, battery-powered IoT sensor nodes, automotive body control modules, and medical handheld diagnostic devices requiring stable component supply and long-term production continuity.

Supply support for MAX6385XS18D2-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, and computing applications, emphasizing low power, high reliability, and small form factor.

The MAX6381–MAX6390 family delivers ultra-low-power, factory-trimmed supervisory circuits targeting space- and energy-constrained embedded systems where deterministic reset behavior is mission-critical.

FAQ

What is the exact reset threshold voltage of MAX6385XS18D2-T and how accurate is it over temperature?

The MAX6385XS18D2-T has a factory-set reset threshold of 1.80V, with ±2.5% accuracy guaranteed over the full operating temperature range of –40°C to +125°C. This means the actual threshold falls between 1.755V and 1.845V at +25°C, and between 1.755V and 1.845V across the entire temperature range - critical for reliable brownout detection in 1.8V systems. The MAX6385XS18D2-T uses laser-trimmed BiCMOS technology to achieve this stability.

Does MAX6385XS18D2-T require an external pullup resistor on the RESET pin?

No, MAX6385XS18D2-T does not require an external pullup resistor on the RESET pin because it features an active-high push-pull output. The internal driver actively pulls RESET high during assertion and low during deassertion. This eliminates external components and ensures fast, rail-to-rail transitions - a key advantage over open-drain alternatives. The MAX6385XS18D2-T's push-pull architecture is confirmed in the device selector guide and pin description tables.

What is the function of the MR pin on MAX6385XS18D2-T and how should it be used?

The MR (Manual Reset) pin on MAX6385XS18D2-T is an active-low input that forces a reset when pulled to GND. It includes a 63kΩ internal pullup resistor to VCC, so it can be left unconnected if unused. To implement manual reset, connect a normally open momentary switch between MR and GND. The MAX6385XS18D2-T guarantees MR-to-RESET delay of ≤200ns and supports TTL/CMOS logic levels - no external debounce circuitry is needed.

Can MAX6385XS18D2-T operate reliably when VCC drops below 1.8V?

Yes, MAX6385XS18D2-T guarantees correct RESET output logic state down to VCC = 1.0V, well below its 1.8V reset threshold. This ensures deterministic behavior during deep brownout or battery discharge, preventing spurious releases. The device continues asserting RESET until VCC rises above 1.8V and remains above threshold for ≥20ms. This specification is explicitly verified in the Electrical Characteristics table and Absolute Maximum Ratings section of the MAX6385XS18D2-T datasheet.

What package type and dimensions does MAX6385XS18D2-T use?

MAX6385XS18D2-T uses a 4-pin SC70 package (outline number 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm with 0.65mm pin pitch. It is RoHS-compliant (+ suffix) and rated for –40°C to +125°C operation. This compact footprint enables high-density placement in portable and automotive electronics where board space is constrained - a key differentiator from larger SOT-23 or SOIC alternatives.