Analog Devices Inc./Maxim Integrated MAX6722UTWGD3+T

Overview

MAX6722UTWGD3+T from Maxim Integrated is a dual-voltage microprocessor supervisory IC monitoring VCC1 (4.625V threshold) and VCC2 (3.075V threshold), with manual reset input, watchdog timer (35s startup / 1.12s normal timeout), and 210ms reset timeout period. It operates in 6-pin SOT23-6 package over -40°C to +85°C and delivers 14µA typical supply current at 3.6V for battery-sensitive telecom and portable systems.

For engineers reviewing the MAX6722UTWGD3+T datasheet, MAX6722UTWGD3+T pinout, MAX6722UTWGD3+T application, or MAX6722UTWGD3+T equivalent, key selection criteria include dual-supply reset thresholds, guaranteed reset validity down to VCC = 0.8V, push-pull RST output referenced to VCC1, and integrated watchdog with long/short dual-mode timing - all critical for reliable power sequencing in multivoltage embedded controllers.

Technical Context

The MAX6722UTWGD3+T implements two independent voltage comparators with factory-trimmed thresholds (VTH1 = 4.625V, VTH2 = 3.075V), a 210ms minimum reset timeout timer, and a dual-mode watchdog with 35s initial startup period and 1.12s normal operation timeout. Its push-pull RST output is referenced to VCC1 and guarantees valid logic state down to VCC1 or VCC2 = 0.8V.

It integrates a manual reset input (MR) with internal 50kΩ pullup to VCC1, glitch rejection of 100ns, and MR-to-reset delay of 200ns. The watchdog input (WDI) clears on any edge transition and restarts the 1.12s timeout after the first valid edge post-reset.

Key Specifications

Pinout & Package

MAX6722UTWGD3+T is housed in a 6-pin SOT23-6 package (2.9mm × 1.6mm × 1.1mm), RoHS-compliant and lead-free (+T suffix). Pin 1 is marked with a dot; device orientation follows JEDEC MO-178AB standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6722UTWGD3+T, MAX6722UTWD3+T removes watchdog capability but retains identical dual-threshold supervision and reset timing, while TPS3808G33DBVR offers lower cost for single-rail use but requires added design effort to replicate dual-supply coverage and watchdog safety.

Availability

MAX6722UTWGD3+T is available at Aetrix Electronics and suitable for telecom infrastructure, industrial PLCs, portable medical devices, and network router control planes requiring stable component supply across extended product lifecycles.

Supply support for MAX6722UTWGD3+T 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 communications applications.

The MAX6715–MAX6729 family delivers ultra-low-voltage, dual/triple-supply microprocessor supervisors optimized for space-constrained, multirail systems where reliability, low quiescent current, and guaranteed reset behavior under brownout are mandatory.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6722UTWGD3+T?

The MAX6722UTWGD3+T has factory-trimmed reset thresholds of 4.625V for VCC1 (primary supply) and 3.075V for VCC2 (secondary supply), as indicated by the "WG" suffix per Maxim's Reset Voltage Threshold Suffix Guide. These values are specified with ±1.5% tolerance over temperature and ensure precise supervision of standard 5V and 3.3V rails without external adjustment.

Does the MAX6722UTWGD3+T include a watchdog timer, and what are its timing modes?

Yes, the MAX6722UTWGD3+T includes a dual-mode watchdog timer. After each reset event (power-up, MR, or brownout), it enters a 35s minimum startup mode to accommodate lengthy system initialization. Once the first valid WDI edge occurs, it switches to a 1.12s minimum normal timeout mode - both timings are guaranteed over -40°C to +85°C and enable robust software hang detection in the MAX6722UTWGD3+T.

What type of reset output does the MAX6722UTWGD3+T provide, and how is it driven?

The MAX6722UTWGD3+T provides an active-low push-pull reset output (RST) referenced to VCC1. Unlike open-drain variants, it actively drives high (to VCC1) and low (to GND) without requiring an external pullup resistor. This simplifies interface design with microprocessors having bidirectional reset pins - a 4.7kΩ series resistor suffices to prevent contention, making the MAX6722UTWGD3+T ideal for compact, low-component-count implementations.

How does the MAX6722UTWGD3+T guarantee valid reset operation at low supply voltages?

The MAX6722UTWGD3+T guarantees correct reset output logic state down to VCC1 or VCC2 = 0.8V, verified across temperature. This ensures deterministic reset assertion during deep brownout conditions where other supervisors may fail. The internal comparator and output driver remain functional, allowing the MAX6722UTWGD3+T to maintain system integrity even as input rails collapse - a critical feature for fail-safe operation in industrial and telecom equipment.

What is the function of the MR pin on the MAX6722UTWGD3+T, and what are its electrical characteristics?

The MR (Manual Reset) pin on the MAX6722UTWGD3+T is an active-low input with an internal 50kΩ pullup resistor to VCC1. A logic-low pulse ≥1µs forces reset assertion for the full 210ms timeout period. It rejects glitches ≤100ns and exhibits 200ns delay from MR rising edge to RST deassertion. Leaving MR unconnected defaults to inactive high, making the MAX6722UTWGD3+T ready for panel-mounted pushbutton integration without external biasing.