Analog Devices Inc./Maxim Integrated MAX6720UTYDD3+

Overview

MAX6720UTYDD3+ from Maxim Integrated is a triple-voltage microprocessor supervisory circuit in SOT23-6 package, monitoring VCC1 (4.625V threshold), VCC2 (3.075V threshold), and an externally adjustable RSTIN input (626.5mV reference). It asserts active-low push-pull reset for ≥210ms after any supply drop, supports manual reset and watchdog timer, and operates from -40°C to +85°C. Used in telecom power systems requiring reliable dual-rail brownout detection and auxiliary voltage supervision.

For engineers reviewing the MAX6720UTYDD3+ datasheet, MAX6720UTYDD3+ pinout, MAX6720UTYDD3+ application, or MAX6720UTYDD3+ equivalent, key selection criteria include its 4.625V/3.075V factory-trimmed dual-thresholds, 210ms reset timeout, push-pull RST output referenced to VCC1, RSTIN-adjustable third-voltage monitoring down to 0.626V, and guaranteed reset validity with VCC1 or VCC2 ≥ 0.8V.

Technical Context

The MAX6720UTYDD3+ implements a dual-comparator architecture with independent VCC1 and VCC2 sensing paths feeding into a shared reset timeout timer. Its RSTIN input uses a dedicated 626.5mV internal reference to enable precise third-supply monitoring via external resistor divider, decoupled from primary rail thresholds.

Reset assertion logic combines ORed fault conditions (VCC1/VCC2 undervoltage, RSTIN low, MR low) with a monotonic timeout counter that restarts on any new fault before timeout completion. The push-pull RST output is actively driven high (≥0.8×VCC1) and low (≤0.4V at 3.2mA sink), eliminating external pull-up requirements.

Key Specifications

Pinout & Package

MAX6720UTYDD3+ is housed in a 6-pin SOT23-6 package with gull-wing leads, 1.27mm pitch, and 2.9mm × 1.6mm footprint. Thermal pad not present; standard reflow profile applies.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX6720UTYDD3+, the MAX6720UTYDD5+ offers double the reset timeout (420ms) with identical voltage thresholds and pinout, while the TPS3808G33DBVR provides lower-cost single-rail supervision but cannot replace the dual/third-voltage monitoring capability essential for complex power architectures.

Availability

MAX6720UTYDD3+ is available at Aetrix Electronics and suitable for telecom infrastructure, industrial control systems, and medical diagnostics equipment requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.

Supply support for MAX6720UTYDD3+ 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 management, sensing, and interface applications, serving industrial, automotive, and communications markets.

The MAX6715–MAX6729 family delivers ultra-low-voltage, multi-rail supervisory circuits optimized for space-constrained systems needing reliable power monitoring with minimal external components and guaranteed operation down to 0.8V supply.

FAQ

What voltage thresholds does the MAX6720UTYDD3+ monitor?

The MAX6720UTYDD3+ monitors VCC1 at 4.625V (±1.5%), VCC2 at 3.075V (±1.5%), and a third voltage via RSTIN using a 626.5mV internal reference. These values are factory-trimmed and specified in the Reset Voltage Threshold Suffix Guide - the "YD" suffix in MAX6720UTYDD3+ directly encodes 4.625V/3.075V. RSTIN threshold is fixed and not adjustable in value, only in monitored voltage level via external resistor divider.

Does the MAX6720UTYDD3+ support manual reset functionality?

Yes, the MAX6720UTYDD3+ includes an active-low manual reset input (MR) on Pin 3 with an internal 50kΩ pullup to VCC1. A logic-low pulse ≥1µs on MR forces reset assertion for the full 210ms timeout period, regardless of supply status. This allows system-level reset initiation via pushbutton, FPGA GPIO, or test equipment - a key feature confirmed in the Selector Guide and Pin Description tables.

What is the reset output type and drive capability of the MAX6720UTYDD3+?

The MAX6720UTYDD3+ features a push-pull active-low RST output on Pin 1, referenced to VCC1. It drives low to ≤0.4V at 3.2mA sink current and high to ≥0.8×VCC1 at 800µA source current. This eliminates external pull-up resistors and ensures robust interfacing with µP reset inputs - a distinguishing feature versus open-drain variants like MAX6719, explicitly documented in the Electrical Characteristics table.

Can the MAX6720UTYDD3+ monitor a third supply voltage?

Yes, the MAX6720UTYDD3+ supports third-supply monitoring via the RSTIN input (Pin 6), which compares the applied voltage against a precise 626.5mV internal reference. Using an external resistor divider, users can configure monitoring thresholds from 0.626V up to >5V. This capability is confirmed in the General Description, Selector Guide (listing MAX6720 as a 3-monitor device), and RSTIN Electrical Characteristics section.

What is the guaranteed operating voltage range for valid reset output from the MAX6720UTYDD3+?

The MAX6720UTYDD3+ guarantees correct reset output logic state (high/low) as long as either VCC1 or VCC2 remains ≥0.8V - a critical specification for brownout recovery scenarios. This is explicitly stated in the General Description and Absolute Maximum Ratings sections, and verified in the Electrical Characteristics table under "Reset Output Logic Options" and "Guaranteed Reset Valid Down to VCC1 or VCC2 = 0.8V".