Analog Devices Inc./Maxim Integrated MAX6377UR31+

Overview

MAX6377UR31+ from Maxim Integrated is an ultra-low-power, open-drain, active-low voltage detector with a factory-trimmed threshold of 3.08V ±2.5%, 500nA supply current, and operation down to 1V VCC - designed for precision battery monitoring and power-supply supervision in portable equipment.

For engineers reviewing the MAX6377UR31+ datasheet, MAX6377UR31+ pinout, MAX6377UR31+ application, or MAX6377UR31+ equivalent, this device serves as a reliable reset supervisor where low quiescent current, transient immunity, and guaranteed logic state at low VCC are critical selection criteria.

Technical Context

The MAX6377UR31+ implements a precision bandgap reference and comparator with internally trimmed resistors to set its 3.08V detection threshold. It asserts an active-low output (open-drain) when VCC falls below VTH and maintains correct logic state down to 1V VCC.

It features built-in immunity to fast negative-going VCC transients (≤20µs at 100mV overdrive), propagation delay of 6.3µs (typical), and ±2.5% threshold accuracy across –40°C to +85°C - all without external components or trimming.

Key Specifications

Pinout & Package

MAX6377UR31+ is housed in a 3-pin SOT23-3 package (lead-free, +T suffix), with 1.3mm × 2.9mm footprint and gull-wing leads compatible with standard reflow processes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV803EB30DBZR and TPS3808G30DBVR, the MAX6377UR31+ offers optimal balance of ultra-low ICC, precise 3.08V threshold, open-drain versatility, and minimal footprint - making it ideal for cost- and power-constrained single-rail supervision.

Availability

MAX6377UR31+ is available at Aetrix Electronics and suitable for portable medical sensors, industrial IoT edge nodes, smart meter backup power, and POS terminal power sequencing requiring stable component supply and long-term lifecycle support.

Supply support for MAX6377UR31+ 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, automotive, and computing applications.

The MAX6375–MAX6380 family was engineered specifically for ultra-low-power voltage supervision in battery-critical systems - prioritizing nanoscale ICC, factory-trimmed accuracy, and robust transient rejection in minimal 3-pin packages.

FAQ

What is the exact reset threshold voltage of MAX6377UR31+ and how accurate is it?

The MAX6377UR31+ has a factory-trimmed nominal reset threshold of 3.08V, with ±2.5% accuracy over the full –40°C to +85°C temperature range. This specification is guaranteed by design and validated across process corners, ensuring reliable detection for 3.3V supply rails with defined safety margin. The MAX6377UR31+ achieves this without external resistors or calibration.

Does MAX6377UR31+ require an external pull-up resistor on its OUT pin?

Yes, the MAX6377UR31+ features an active-low open-drain output, so an external pull-up resistor is mandatory to establish a valid high logic level. The resistor value must be selected to ensure VOL ≤0.4V at ISINK = 100µA (per datasheet), typically 10kΩ–100kΩ depending on bus capacitance and rise-time requirements. The MAX6377UR31+ itself does not include internal pull-up circuitry.

Can MAX6377UR31+ operate reliably below 2.0V VCC?

Yes, the MAX6377UR31+ is fully specified to maintain correct output logic state down to 1.0V VCC - a key differentiator for ultra-low-voltage applications such as energy-harvesting systems or deeply discharged battery scenarios. Its internal bandgap reference and comparator remain functional and monotonic throughout this range, and the MAX6377UR31+ continues to assert OUT low when VCC < 3.08V even at 1.2V input.

What is the maximum transient duration that MAX6377UR31+ can ignore at its VCC pin?

The MAX6377UR31+ rejects negative-going VCC transients up to 20µs in duration when the overdrive (VTH – VCC) is 100mV, per the Typical Operating Characteristics graph. As overdrive increases, the allowable pulse width decreases - e.g., ~5µs at 200mV overdrive. This built-in immunity prevents false resets caused by switching noise or load transients, and is intrinsic to the MAX6377UR31+ design without external filtering.

Is MAX6377UR31+ pin-compatible with other members of the MAX6375–MAX6380 family?

Yes, all MAX6375–MAX6380 variants - including MAX6377UR31+ - share identical 3-pin SOT23-3 pinout (VCC, GND, OUT) and SC70-3 pinout. This allows direct substitution within the same package type when only threshold voltage or output configuration differs. However, note that MAX6375/MAX6378 use push-pull outputs, while MAX6377UR31+ uses open-drain - so external circuitry (e.g., pull-up) must match the output type.