Analog Devices Inc./Maxim Integrated MAX6377XR31+

Overview

MAX6377XR31+ from Maxim Integrated is an ultra-low-power, open-drain, active-low voltage detector designed for precision supply monitoring in battery-powered systems. It features a factory-trimmed 3.08V threshold (±2.5% over temperature), 500nA supply current, and operates down to 1V VCC. Its primary circuit role is asserting a logic-low reset signal when input voltage falls below threshold - used in portable equipment power sequencing and Li+-battery undervoltage protection.

For engineers reviewing the MAX6377XR31+ datasheet, MAX6377XR31+ pinout, MAX6377XR31+ application, or MAX6377XR31+ equivalent, key selection criteria include its SC70-3 open-drain output configuration, guaranteed 1V minimum operating voltage, ±2.5% threshold accuracy across -40°C to +85°C, and immunity to sub-200µs VCC transients at 100mV overdrive.

Technical Context

The MAX6377XR31+ implements a precision bandgap reference and comparator with internally trimmed resistors to set its 3.08V detection threshold. It uses no external components and ignores fast negative-going VCC transients - propagation delay is 6.3µs (falling) and 9.5µs (rising) under typical conditions.

This device belongs to the MAX6375–MAX6380 family of single-function voltage detectors. Its open-drain output requires an external pull-up and sinks up to 100µA at 0.4V (VOL) while asserted, supporting interface flexibility across logic voltage domains up to 5.5V.

Key Specifications

Pinout & Package

MAX6377XR31+ is housed in a 3-pin SC70-3 package (2.0mm × 2.1mm × 0.95mm), optimized for space-constrained portable designs. Pin 1 = GND, Pin 2 = OUT (open-drain), Pin 3 = VCC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage detector applications.

Compared with TLV803EB30DBZR and APX803S-30SA-7, the MAX6377XR31+ offers superior transient immunity (200µs rejection at 100mV overdrive), guaranteed 1V operation, and factory-trimmed 3.08V threshold optimized for 3.3V system margins - making it preferred for high-reliability portable and medical applications.

Availability

MAX6377XR31+ is available at Aetrix Electronics and suitable for portable medical sensors, wearables with Li+ battery, and industrial IoT edge nodes requiring stable component supply, long-term availability, and lead-free compliance.

Supply support for MAX6377XR31+ 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, mixed-signal, and power management ICs for demanding industrial, medical, and communications applications.

The MAX6375–MAX6380 series was developed specifically for ultra-low-power supply monitoring in battery-critical systems - prioritizing nanoscale current, guaranteed low-VCC operation, and factory-trimmed thresholds to eliminate calibration overhead.

FAQ

What is the exact reset threshold voltage of the MAX6377XR31+?

The MAX6377XR31+ has a factory-trimmed nominal reset threshold of 3.08V, with ±2.5% accuracy guaranteed over the full operating temperature range of -40°C to +85°C. This value is confirmed in Table 1 of the official datasheet and corresponds to the "R31" suffix. The actual threshold remains stable across load and supply variations due to its internal bandgap reference and trimmed resistor network.

Does the MAX6377XR31+ require an external pull-up resistor on its OUT pin?

Yes, the MAX6377XR31+ features an open-drain output, so an external pull-up resistor is mandatory for proper logic-level generation. The datasheet specifies that the pull-up may connect to any voltage up to 5.5V, allowing interoperability with 1.8V, 3.3V, or 5V logic domains. Typical values range from 10kΩ to 100kΩ depending on bus capacitance and sink-current requirements.

Can the MAX6377XR31+ operate reliably below 2.0V VCC?

Yes - the MAX6377XR31+ is fully specified to operate down to 1.0V VCC, and its output remains valid (active-low when VCC < 3.08V) across this entire range. This capability is critical for applications such as end-of-life Li+ battery monitoring, where supply voltage may decay below 2.0V while still requiring functional reset assertion.

What package type does the MAX6377XR31+ use, and is it RoHS-compliant?

The MAX6377XR31+ uses the SC70-3 package (2.0mm × 2.1mm × 0.95mm) and is supplied in lead-free, RoHS-compliant form - indicated by the "+" suffix in the part number. The "+T" ordering variant confirms tape-and-reel packaging with Pb-free terminations, meeting JEDEC J-STD-020 moisture sensitivity level 1 requirements.

How does the MAX6377XR31+ handle fast supply transients?

The MAX6377XR31+ rejects fast negative-going VCC transients up to 200µs in duration when the overdrive (VTH – VCC) is 100mV, as shown in Figure 4 of the datasheet. This built-in immunity prevents false resets caused by switching noise from DC/DC converters or digital load transients - a key differentiator versus basic comparators without integrated filtering.