Analog Devices Inc./Maxim Integrated MAX6377UR28+

Overview

MAX6377UR28+ from Maxim Integrated is an ultra-low-power, open-drain, active-low voltage detector optimized for battery and power-supply monitoring in portable systems. It features a factory-trimmed 2.80V threshold (±2.5% over temperature), 500nA supply current at +25°C, and guaranteed operation down to VCC = 1V. Its role is to assert a logic-low output when supply voltage falls below the trip point - used in microcontroller reset supervision and load-switch enable control.

For engineers reviewing the MAX6377UR28+ datasheet, MAX6377UR28+ pinout, MAX6377UR28+ application, or MAX6377UR28+ equivalent, key selection criteria include its SOT23-3 open-drain output configuration, 2.80V detection accuracy, transient immunity up to 200µs at 100mV overdrive, and compatibility with 1.2V–5.5V supply rails in space-constrained battery-powered designs.

Technical Context

The MAX6377UR28+ implements a precision bandgap reference and comparator with internally trimmed resistors to set its 2.80V threshold without external components. Its open-drain output requires an external pull-up and sinks ≥100µA when asserted, supporting interface with diverse logic families up to 5.5V.

Designed for immunity to fast VCC transients, it suppresses output pulses for negative-going glitches ≤200µs at 100mV overdrive (VTH − VCC), with propagation delay of 6.3µs (typ) and hysteresis of 100mV - ensuring stable reset assertion during brownout recovery.

Key Specifications

Pinout & Package

MAX6377UR28+ is housed in a lead-free 3-pin SOT23-3 package (JEDEC MO-178AA), footprint-compatible with SC70-3 but with higher power dissipation rating (320mW at +70°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV803EB28DBZR and APX803S-28SA-7, the MAX6377UR28+ offers optimal balance of ultra-low current, open-drain configurability, and tight 100mV hysteresis - making it preferred for battery-powered systems requiring reset bus sharing and minimal leakage.

Availability

MAX6377UR28+ is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, smart utility meters, and asset tracking beacons requiring stable component supply and long-term obsolescence management.

Supply support for MAX6377UR28+ 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 connectivity applications, with emphasis on high-reliability, low-power solutions.

The MAX6375–MAX6380 family was developed specifically for ultra-low-power voltage monitoring in battery-critical systems - delivering factory-trimmed accuracy and transient immunity in sub-1mm² packages.

FAQ

What is the exact reset threshold voltage of the MAX6377UR28+?

The MAX6377UR28+ has a factory-trimmed nominal reset threshold of 2.80V, with guaranteed accuracy of ±2.5% over the full operating temperature range (−40°C to +85°C). This value is confirmed in Table 1 of the datasheet under suffix "R28", and applies specifically to the MAX6377UR28+ variant - not to other members of the MAX6375–MAX6380 family.

Does the MAX6377UR28+ require an external pull-up resistor on its OUT pin?

Yes, the MAX6377UR28+ features an open-drain active-low output, so an external pull-up resistor is mandatory to establish a valid high logic level. The datasheet specifies that the pull-up may connect to any supply up to 5.5V, and recommends selecting a value that ensures VOL ≤0.4V at ISINK = 100µA while meeting downstream input leakage requirements - typically 10kΩ to 100kΩ.

Can the MAX6377UR28+ operate reliably below 1.8V supply voltage?

Yes, the MAX6377UR28+ is fully specified to operate down to VCC = 1.2V and guarantees correct output logic state (active-low when VCC < 2.80V) for VCC as low as 1.0V. This capability is explicitly stated in the General Description and Electrical Characteristics tables, enabling use in deeply discharged lithium-based batteries and low-voltage energy-harvesting systems.

What is the maximum transient duration the MAX6377UR28+ can ignore at 100mV overdrive?

At a threshold overdrive of 100mV (i.e., VTH − VCC = 100mV), the MAX6377UR28+ suppresses output pulses for negative-going VCC transients up to 200µs in duration, as shown in Figure MAX6375-04 of the datasheet. This transient immunity prevents false resets caused by switching regulator noise or ESD-induced supply dips.

Is the MAX6377UR28+ pin-compatible with other devices in the MAX6375–MAX6380 family?

Yes, all MAX6375–MAX6380 variants - including MAX6377UR28+ - share identical 3-pin SOT23-3 and SC70-3 footprints and pinouts (GND, OUT, VCC). However, output logic type differs: MAX6377UR28+ is open-drain active-low, whereas MAX6376 variants are push-pull active-high - so direct substitution requires verification of downstream logic interface requirements.