Analog Devices Inc./Maxim Integrated MAX6720AUTTGD3+

Overview

MAX6720AUTTGD3+ from Maxim Integrated is a dual-voltage microprocessor supervisory circuit in 6-pin SOT23 package, monitoring VCC1 (primary supply) and VCC2 (secondary supply) with factory-trimmed reset thresholds of 3.075V (VTH1) and 0.788V (VTH2), 210ms minimum reset timeout, and guaranteed reset validity down to VCC1 or VCC2 = 0.8V. It supports triple-voltage monitoring via RSTIN input (626.5mV internal reference), and operates across –40°C to +125°C for industrial embedded power sequencing.

For engineers reviewing the MAX6720AUTTGD3+ datasheet, MAX6720AUTTGD3+ pinout, MAX6720AUTTGD3+ application, or MAX6720AUTTGD3+ equivalent, key selection criteria include dual-supply threshold accuracy, 210ms reset timeout compliance, RSTIN-adjustable third-voltage monitoring capability, push-pull active-low RST output referenced to VCC1, and immunity to sub-20µs VCC transients.

Technical Context

The MAX6720AUTTGD3+ integrates two independent voltage comparators with hysteresis (0.5% typical), a precision 626.5mV internal reference for RSTIN, and a digital reset timer with fixed 210ms (min) timeout period. Its reset logic asserts RST low when either VCC1 falls below 3.075V or VCC2 drops below 0.788V - or when RSTIN falls below 626.5mV - and holds RST low for the full timeout after all monitored voltages recover.

This device uses a push-pull RST output referenced to VCC1, eliminating external pull-up requirements, and guarantees valid reset assertion even as VCC1 or VCC2 decays to 0.8V. It draws only 14µA typical supply current at 3.6V and features built-in immunity to short VCC transients (<20µs at 100mV overdrive).

Key Specifications

Pinout & Package

MAX6720AUTTGD3+ is housed in a 6-pin SOT23 package (2.9mm × 1.6mm × 1.1mm, 0.95mm pitch), RoHS-compliant and lead-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6720AUTTGD3+, MAX6720AUTTGD5+ offers extended reset duration but identical threshold accuracy and RSTIN functionality, while TPS3808G33DBVR reduces power consumption by 82% but sacrifices dual-supply supervision and third-voltage adjustability - making it unsuitable for multirail validation.

Availability

MAX6720AUTTGD3+ is available at Aetrix Electronics and suitable for industrial PLC power sequencing, automotive ADAS camera modules, and medical infusion pump controllers requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MAX6720AUTTGD3+ 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, and communications markets.

The MAX6715A–MAX6729A family delivers ultra-low-voltage µP supervisory circuits optimized for space-constrained, multirail embedded systems where reliability across –40°C to +125°C and minimal quiescent current are critical.

FAQ

What is the exact reset timeout period for MAX6720AUTTGD3+?

The MAX6720AUTTGD3+ has a guaranteed minimum reset timeout period of 210ms. This value is factory-trimmed and specified across –40°C to +125°C. Typical timeout is 210ms, with maximum values up to 280ms under worst-case conditions per the Reset Timeout Period Suffix Guide (D3 suffix). The timeout begins after all monitored supplies exceed their thresholds and ends with RST returning high.

Does MAX6720AUTTGD3+ support monitoring a third voltage, and how is it implemented?

Yes, MAX6720AUTTGD3+ supports third-voltage monitoring via its RSTIN pin, which connects to an internal 626.5mV precision reference. A resistor-divider network between the target supply and ground sets the trip point using V_{EXT_TH} = 626.5mV × (R1 + R2)/R2. Input leakage is <100nA, enabling high-value resistors to minimize power draw without compromising accuracy.

What is the function of the MR pin on MAX6720AUTTGD3+, and does it require external components?

The MR pin on MAX6720AUTTGD3+ is an active-low manual-reset input with an internal 50kΩ pullup to VCC1. Pulling MR low forces an immediate reset assertion for the full 210ms timeout period, then holds reset for the timeout after MR returns high. No external components are required - MR can be left unconnected, tied to VCC1, or driven by a momentary switch to GND.

Is MAX6720AUTTGD3+ compatible with 1.8V VCC2 supplies, and what is its minimum operating voltage?

MAX6720AUTTGD3+ supports VCC2 from 0.8V to 5.5V, so it fully supports 1.8V secondary supplies. Its reset output remains valid and functional as long as either VCC1 or VCC2 remains ≥0.8V - a key feature enabling operation during deep brownout conditions where other supervisors fail. The 0.788V VCC2 threshold is optimized for 0.9V core rails but functions reliably at 1.8V.

What type of reset output does MAX6720AUTTGD3+ provide, and what are its drive capabilities?

MAX6720AUTTGD3+ provides a push-pull active-low RST output referenced to VCC1. It sources ≥0.8×VCC1 at 800µA and sinks ≤0.4V at 3.2mA (VCC1 ≥4.5V), eliminating the need for external pull-up resistors. This differs from open-drain variants in the same family and simplifies interface to MCUs with unidirectional reset pins.