Analog Devices Inc./Maxim Integrated MAX6718UKWGD3

Overview

MAX6718UKWGD3 from Maxim Integrated is a dual-voltage microprocessor supervisory circuit in 5-pin SOT23 package, monitoring VCC1 (primary supply) and VCC2 (secondary supply) with factory-trimmed reset thresholds of 2.925V (VTH1) and 1.388V (VTH2), 210ms minimum reset timeout, push-pull active-low RST output, and guaranteed reset validity down to VCC1 or VCC2 = 0.8V - used in portable battery-operated equipment for reliable power-on reset and brownout detection.

For engineers reviewing the MAX6718UKWGD3 datasheet, MAX6718UKWGD3 pinout, MAX6718UKWGD3 application, or MAX6718UKWGD3 equivalent, key selection criteria include dual-supply threshold accuracy, 210ms reset timeout stability over -40°C to +125°C, push-pull RST drive capability referenced to VCC1, low 14µA typical supply current at 3.6V, and immunity to sub-20µs VCC transients.

Technical Context

The MAX6718UKWGD3 integrates two independent voltage comparators with hysteresis (0.5% of VTH), a precision internal reference (626.5mV for auxiliary inputs), and a digital timeout counter that restarts on any threshold violation before timeout completion. It operates with VCC1 from 0.8V–5.5V and VCC2 from 0.8V–5.5V, maintaining valid reset logic state even when either supply drops to 0.8V.

This device implements a fixed-function supervisory architecture with no configuration registers or I²C interface: reset assertion is purely analog-comparator–driven, and the 210ms timeout is hardwired via internal RC timing. The push-pull RST output is referenced to VCC1 and sinks up to 3.2mA at VCC1 ≥ 4.5V while maintaining VOL ≤ 0.4V.

Key Specifications

Pinout & Package

MAX6718UKWGD3 is housed in a 5-pin SOT23 package (2.9mm × 1.6mm × 1.1mm height), RoHS-compliant, with gull-wing leads and thermal pad not connected internally.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-voltage supervisory applications.

Compared with TPS3808G18DBVR and ADM6705ARTZ-REEL7, MAX6718UKWGD3 uniquely delivers factory-trimmed dual-threshold supervision (2.925V/1.388V), full -40°C to +125°C operation, and push-pull RST in a 5-pin SOT23 - eliminating external components and enabling compact, high-reliability designs in automotive and industrial edge nodes.

Availability

MAX6718UKWGD3 is available at Aetrix Electronics and suitable for battery-powered IoT sensor nodes, industrial PLC I/O modules, automotive body control units, medical point-of-care monitors, and telecom line cards requiring stable component supply across extended temperature ranges.

Supply support for MAX6718UKWGD3 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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, communications, and computing markets.

The MAX6715A–MAX6729A family was designed specifically for ultra-low-voltage, dual- or triple-rail microprocessor supervision in space-constrained, thermally demanding applications - emphasizing precision threshold matching, low IQ, and guaranteed operation down to 0.8V supply.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on MAX6718UKWGD3?

The MAX6718UKWGD3 has factory-trimmed reset thresholds of 2.925V (typical, ±37.5mV) for VCC1 and 1.388V (typical, ±37.5mV) for VCC2, as defined by the 'W' and 'G' suffixes in its part number per Maxim's Reset Voltage Threshold Suffix Guide. These values are measured at TA = +25°C and exhibit ±20ppm/°C tempco over temperature.

Does MAX6718UKWGD3 support monitoring a third voltage rail?

No, MAX6718UKWGD3 is a dual-supply supervisor and does not include the RSTIN input required for adjustable third-rail monitoring. That functionality is present only in variants like MAX6719A/MAX6720A (5-pin with RSTIN) or MAX6723A–MAX6727A (6- or 8-pin). MAX6718UKWGD3 monitors only VCC1 and VCC2.

What is the function of the MR pin on MAX6718UKWGD3, and how should it be used?

The MR pin on MAX6718UKWGD3 is an active-low manual-reset input with an internal 50kΩ pullup to VCC1. Pulling MR low forces immediate RST assertion for the full 210ms timeout period. It can be driven by a momentary switch to GND or CMOS logic; leaving it unconnected defaults to inactive (RST controlled only by supply voltages).

Is MAX6718UKWGD3 compatible with push-pull or open-drain microcontroller reset inputs?

MAX6718UKWGD3 features a push-pull active-low RST output referenced to VCC1, making it directly compatible with standard µP reset pins requiring active-low assertion. For µPs with bidirectional reset I/O, a 4.7kΩ series resistor between RST and the µP pin prevents contention - as documented in Maxim's Application Note 4319.

What is the maximum supply voltage the MAX6718UKWGD3 can tolerate on VCC1 and VCC2 pins?

The absolute maximum rating for VCC1 and VCC2 on MAX6718UKWGD3 is +6V, but the recommended operating range is 0.8V to 5.5V per the Electrical Characteristics table. Operation above 5.5V risks permanent damage, and below 0.8V invalidates guaranteed reset behavior - though the device may still function down to 0V with external pulldown/pullup.