Analog Devices Inc./Maxim Integrated MAX6381LT16D3+

Overview

MAX6381LT16D3+ from Maxim Integrated is a low-power microprocessor supervisory circuit with factory-set 1.58V reset threshold, 140ms minimum reset timeout, active-low open-drain reset output, and operation down to VCC = 1.0V. It monitors single supply rails in battery-powered and embedded systems, consuming only 3µA at +1.8V and offering ±2.5% threshold accuracy over -40°C to +125°C.

For engineers reviewing the MAX6381LT16D3+ datasheet, MAX6381LT16D3+ pinout, MAX6381LT16D3+ application, or MAX6381LT16D3+ equivalent, key selection criteria include guaranteed reset assertion down to 1V VCC, negative-going transient immunity, SC70-3/µDFN-6 package options, and compatibility with dual-voltage monitoring architectures requiring auxiliary reset inputs.

Technical Context

The MAX6381LT16D3+ implements a precision bandgap-based voltage comparator with internal 1.58V reference and ±2.5% threshold tolerance across full industrial temperature range. Its reset timeout is generated by an on-chip RC timer calibrated for 140ms minimum duration after VCC exceeds threshold.

It features an open-drain RESET output requiring external pull-up, valid logic state guarantee down to VCC = 1.0V, and immunity to sub-100ns VCC transients when overdrive exceeds 100mV - enabling robust operation in noisy power environments without external filtering.

Key Specifications

Pinout & Package

MAX6381LT16D3+ is available in 3-pin SC70-3 (X3-2) and 6-pin µDFN-6 (L611-1) packages. The SC70-3 variant uses all three pins; the µDFN-6 variant leaves pins 3, 5, and 6 unconnected (N.C.).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6381LT16D3+, MAX6326LTRD3+T simplifies BOM by removing the pull-up resistor, while TLV809K33DBZR reduces supply current by 83% but lacks documented VCC transient rejection - making MAX6381LT16D3+ optimal for noisy automotive or industrial settings demanding proven immunity.

Availability

MAX6381LT16D3+ is available at Aetrix Electronics and suitable for battery-powered IoT sensors, industrial PLC I/O modules, and medical wearable monitors requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6381LT16D3+ 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 industrial, automotive, and computing markets.

The MAX6381–MAX6390 family delivers ultra-low-power, high-accuracy reset supervision for resource-constrained embedded systems - specifically engineered for reliable operation in battery-powered, automotive, and harsh-environment applications where supply stability cannot be assumed.

FAQ

What is the exact reset threshold voltage of MAX6381LT16D3+ and how is it specified?

The MAX6381LT16D3+ has a factory-set reset threshold of 1.58V, with ±2.5% tolerance guaranteed over the full operating temperature range of -40°C to +125°C. This value is defined as the minimum voltage (VTH min = 1.54V) at which the device deasserts reset, and maximum voltage (VTH max = 1.61V) at which it asserts reset - ensuring deterministic behavior in brownout conditions for 1.8V logic systems. The "16" suffix in MAX6381LT16D3+ explicitly denotes this 1.58V threshold.

Does MAX6381LT16D3+ support manual reset functionality?

No, MAX6381LT16D3+ does not include a manual reset (MR) input. It belongs to the MAX6381/MAX6382/MAX6383 subgroup, which lacks MR and RESET IN pins. Only MAX6384–MAX6390 variants feature MR, and MAX6387–MAX6390 include RESET IN. The MAX6381LT16D3+ is a single-supply, no-manual-reset supervisor with VCC-only monitoring and open-drain active-low RESET output.

What package options are available for MAX6381LT16D3+ and are they pin-compatible?

MAX6381LT16D3+ is offered in two packages: 3-pin SC70-3 (X3-2) and 6-pin µDFN-6 (L611-1). These are not pin-compatible - the SC70-3 uses pins 1 (GND), 2 (RESET), and 3 (VCC), while the µDFN-6 uses pins 1 (GND), 2 (RESET), 4 (VCC), with pins 3, 5, and 6 designated N.C. Designers must select the appropriate footprint; migration between packages requires PCB revision.

How does the open-drain output of MAX6381LT16D3+ interface with a 3.3V microcontroller reset input?

The open-drain RESET output of MAX6381LT16D3+ requires an external pull-up resistor to the target reset domain voltage - e.g., 3.3V for a 3.3V MCU. A 10kΩ resistor is typical. When asserted (low), the output sinks ≤80µA while holding RESET ≤0.3V. When deasserted (high-impedance), the pull-up defines the logic high level. This enables level-shifting and wired-OR configurations not possible with push-pull outputs.

What is the minimum VCC voltage at which MAX6381LT16D3+ guarantees correct RESET logic state?

MAX6381LT16D3+ guarantees valid RESET output logic state down to VCC = 1.0V. Below this, the internal comparator and output driver may become indeterminate. This specification ensures reliable hold-down during deep brownout events - critical for applications like Li-ion battery systems where VCC can decay below 1.8V but must still maintain controlled reset behavior until complete power loss.