Analog Devices Inc./Maxim Integrated MAX6722UTSHD3+

Overview

MAX6722UTSHD3+ from Maxim Integrated is a dual-voltage microprocessor supervisory circuit in SOT23-6 package, monitoring VCC1 (4.625V threshold) and VCC2 (3.075V threshold) with 210ms reset timeout, push-pull active-low RST output, manual reset input (MR), and watchdog timer (WDI). It guarantees valid reset assertion down to VCC1 or VCC2 = 0.8V and draws only 14µA typical supply current at 3.6V - used in telecom power management and industrial embedded controllers requiring reliable brownout detection.

For engineers reviewing the MAX6722UTSHD3+ datasheet, MAX6722UTSHD3+ pinout, MAX6722UTSHD3+ application, or MAX6722UTSHD3+ equivalent, key selection criteria include its factory-trimmed dual-threshold configuration (4.625V/3.075V), 210ms min reset timeout, push-pull RST output referenced to VCC1, integrated WDI with 35s startup + 1.12s normal watchdog period, and guaranteed operation at VCC ≥ 0.8V.

Technical Context

The MAX6722UTSHD3+ implements dual independent voltage comparators with internal 20ppm/°C tempco thresholds, a programmable reset timeout timer, and a dual-mode watchdog (35s initial / 1.12s normal) that clears on any WDI edge. Its MR input features a 50kΩ internal pullup and 100ns glitch rejection.

This device uses BiCMOS process (1072 transistors) and asserts RST low when either VCC1 falls below 4.625V or VCC2 drops below 3.075V, maintaining reset for ≥210ms after both supplies recover. Reset logic remains valid even if one supply collapses to 0.8V while the other remains active.

Key Specifications

Pinout & Package

MAX6722UTSHD3+ 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; pinout follows standard SOT23 orientation with GND at pin 2.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6722UTSHD3+, MAX6722UTSMD3+ trades push-pull drive for open-drain flexibility at identical timing and thresholds, while TPS3808G33DBVR reduces feature set to lower cost and complexity - making it viable only in single-rail, non-watchdog applications.

Availability

MAX6722UTSHD3+ is available at Aetrix Electronics and suitable for telecom infrastructure, industrial PLCs, and medical monitoring equipment requiring stable component supply, long-term lifecycle support, and guaranteed RoHS-compliant sourcing.

Supply support for MAX6722UTSHD3+ 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 reliability and integration.

The MAX6715–MAX6729 family targets multivoltage embedded systems needing compact, low-power supervision - specifically engineered to replace discrete reset circuits in space- and power-constrained telecom, computing, and industrial control designs.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6722UTSHD3+?

The MAX6722UTSHD3+ has factory-trimmed reset thresholds of 4.625V for VCC1 (primary supply) and 3.075V for VCC2 (secondary supply), both specified as falling thresholds with ±1.5% tolerance over temperature. These values are encoded in the "SH" suffix per Maxim's Reset Voltage Threshold Suffix Guide and are not adjustable. The MAX6722UTSHD3+ guarantees correct reset assertion even when either supply drops to 0.8V while the other remains active.

Does the MAX6722UTSHD3+ include a watchdog timer, and what are its timing modes?

Yes, the MAX6722UTSHD3+ includes a dual-mode watchdog timer with two distinct periods: a 35s minimum startup timeout after any reset event (power-up, MR, or watchdog timeout), followed by a 1.12s minimum normal-mode timeout triggered by the first valid WDI edge. This architecture allows safe boot completion before enforcing strict runtime supervision. The WDI input accepts TTL/CMOS levels and clears the timer on any rising or falling edge.

What type of reset output does the MAX6722UTSHD3+ provide, and how is it configured?

The MAX6722UTSHD3+ provides a push-pull active-low RST output referenced to VCC1, eliminating the need for an external pullup resistor. It drives low during fault conditions (VCC1 < 4.625V or VCC2 < 3.075V) and holds low for ≥210ms after both supplies recover. The output can source up to 800µA at VCC1 ≥ 4.5V and sink up to 3.2mA, meeting standard µP reset input requirements without additional components.

Can the MAX6722UTSHD3+ monitor three voltage rails?

No, the MAX6722UTSHD3+ is a dual-voltage supervisor and monitors only VCC1 and VCC2. It does not include RSTIN or PFI inputs - those features appear in variants like MAX6723–MAX6729. The "22" in MAX6722 indicates dual-monitor capability with manual reset and watchdog, but no third-voltage input. For triple-rail monitoring, consider MAX6723UTSHD3+ (with RSTIN) or MAX6728UTSHD3+ (with PFI/PFO).

What is the supply current consumption of the MAX6722UTSHD3+ across operating conditions?

The MAX6722UTSHD3+ draws 14µA typical supply current at 3.6V and +25°C, with total ICC1 + ICC2 ranging from 10µA (VCC1 < 3.6V) to 39µA (VCC1 < 5.5V) across temperature and voltage. Current remains stable over -40°C to +85°C, enabling use in battery-critical applications. The BiCMOS process ensures low leakage, and supply current scales predictably with VCC1/VCC2 levels per the Electrical Characteristics table.