Analog Devices Inc./Maxim Integrated MAX6381LT18D5+T

Overview

MAX6381LT18D5+T from Maxim Integrated is a low-power microprocessor supervisory circuit with factory-set 1.8V reset threshold, 280ms minimum V_CC reset timeout, and active-low push-pull reset output. It monitors single supply voltage in battery-powered systems, guarantees valid reset down to V_CC = 1V, consumes only 3µA at 1.8V, and operates across –40°C to +125°C for industrial embedded control.

For engineers reviewing the MAX6381LT18D5+T datasheet, MAX6381LT18D5+T pinout, MAX6381LT18D5+T application, or MAX6381LT18D5+T equivalent, key selection criteria include reset threshold accuracy (±2.5% over temperature), negative-going transient immunity, SC70/μDFN package compatibility, and absence of manual reset or auxiliary input functionality in this variant.

Technical Context

The MAX6381LT18D5+T implements a precision bandgap-based reset comparator with ±2.5% threshold accuracy from –40°C to +125°C and 60ppm/°C tempco. Its internal timer generates a guaranteed-minimum 280ms reset assertion after V_CC rises above 1.8V, independent of supply ramp rate.

It features an active-low push-pull RESET output capable of sinking 3.2mA at V_CC ≥ 4.5V (V_OL ≤ 0.4V) and sourcing current when deasserted, with logic state validity ensured down to V_CC = 1V. No MR or RESET IN pins are present-this is a dedicated single-supply monitor.

Key Specifications

Pinout & Package

MAX6381LT18D5+T is housed in a 6-pin µDFN package (2mm × 2mm, 0.5mm pitch, exposed pad) with wettable flanks for automated optical inspection. Pin 1 is RESET, Pin 4 is V_CC, Pin 6 is GND; Pins 2, 3, and 5 are no-connect (N.C.) and must remain unconnected per datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326LTR18D5+T and TPS3123E18DBVR, MAX6381LT18D5+T provides the exact 280ms timeout needed for robust 1.8V system startup, lower quiescent current for battery longevity, and native active-low push-pull compatibility with most µP reset inputs-without requiring redesign or additional components.

Availability

MAX6381LT18D5+T is available at Aetrix Electronics and suitable for portable/battery-powered equipment, critical μP and μC power monitoring, and dual voltage systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6381LT18D5+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 communications applications, with emphasis on low-power, high-reliability solutions.

The MAX6381–MAX6390 family delivers single/dual low-voltage µP supervisory circuits optimized for battery-operated and thermally demanding systems, featuring factory-trimmed thresholds, sub-µA quiescent current, and AEC-Q100 qualified variants.

FAQ

What is the exact reset threshold voltage of MAX6381LT18D5+T and how stable is it over temperature?

The MAX6381LT18D5+T has a nominal reset threshold of 1.80V, with guaranteed tolerance of ±2.5% across the full operating temperature range of –40°C to +125°C. This stability is achieved via laser-trimmed bandgap reference and low-tempco design (60ppm/°C), ensuring reliable brownout detection without recalibration in automotive or industrial environments where MAX6381LT18D5+T is deployed.

Does MAX6381LT18D5+T include a manual reset input (MR) or auxiliary voltage monitor (RESET IN)?

No, MAX6381LT18D5+T does not include MR or RESET IN functionality. It is a dedicated single-supply supervisor with only RESET, V_CC, and GND terminals plus three N.C. pins. The "LT" prefix and "D5" suffix identify it as a 6-pin µDFN variant with 1.8V threshold and 280ms timeout-matching the MAX6381 base part number's push-pull active-low configuration without added inputs, as confirmed in the Selector Guide and Pin Configurations.

What is the minimum V_CC level at which MAX6381LT18D5+T guarantees correct RESET output logic state?

MAX6381LT18D5+T guarantees valid RESET output logic state down to V_CC = 1.0V. Below this voltage, the internal circuitry may not maintain defined output behavior. This specification ensures deterministic reset assertion during deep brownout events common in battery discharge profiles, making MAX6381LT18D5+T suitable for applications where power collapse must trigger a controlled shutdown before µP enters undefined states.

Can MAX6381LT18D5+T be used in automotive applications, and what qualification does it hold?

Yes, MAX6381LT18D5+T is rated for –40°C to +125°C operation and is AEC-Q100 qualified (referenced in the Features section). While the specific /V automotive trim version uses different ordering suffixes (e.g., MAX6381LT18D5/V+T), the +T RoHS-compliant 6-pin µDFN package of MAX6381LT18D5+T meets automotive ambient temperature and reliability requirements for non-safety-critical modules such as infotainment power supervisors or body electronics.

What are the absolute maximum ratings for V_CC and RESET pin voltage in MAX6381LT18D5+T?

The absolute maximum V_CC rating for MAX6381LT18D5+T is –0.3V to +6.0V, and the RESET pin (push-pull) withstands –0.3V to (V_CC + 0.3V). Exceeding these limits risks permanent damage. These ratings allow safe operation during hot-swap events or transient overshoots, but sustained operation should remain within the recommended 1.0V–5.5V V_CC range specified in the Electrical Characteristics table for MAX6381LT18D5+T.