Analog Devices Inc./Maxim Integrated MAX6723UTSDD3+T

Overview

MAX6723UTSDD3+T from Maxim Integrated is a triple-voltage microprocessor supervisory circuit in 6-pin SOT23 package, monitoring VCC1 (4.625V threshold), VCC2 (3.075V threshold), and an externally adjustable RSTIN input (626.5mV reference). It asserts active-low open-drain reset for ≥210ms after any supply drop, supports manual reset and watchdog timer, and operates from -40°C to +85°C in telecom and industrial power management systems.

For engineers reviewing the MAX6723UTSDD3+T datasheet, MAX6723UTSDD3+T pinout, MAX6723UTSDD3+T application, or MAX6723UTSDD3+T equivalent, key selection factors include its dual-supply monitoring with factory-trimmed thresholds, 210ms reset timeout, open-drain RST output referenced to VCC1, guaranteed reset validity down to VCC1/VCC2 = 0.8V, and integrated watchdog with 35s startup/1.12s normal timeout.

Technical Context

The MAX6723UTSDD3+T implements a triple-monitoring architecture: primary supply (VCC1) at 4.625V, secondary supply (VCC2) at 3.075V, and auxiliary voltage via RSTIN with 626.5mV internal reference. Its reset logic remains valid even when either VCC1 or VCC2 drops to 0.8V, enabling robust brownout detection in multirail systems.

It features an open-drain RST output (pin 1), manual reset input (MR, pin 3) with 50kΩ internal pullup to VCC1, and watchdog input (WDI, pin 5) supporting dual-mode timing-35s minimum after reset and 1.12s minimum during normal operation. No power-fail or RST2 functionality is included per Selector Guide.

Key Specifications

Pinout & Package

Package: 6-pin SOT23-6, surface-mount, lead-free (+T suffix), footprint compatible with industry-standard 0.95mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6723UTSDD3+T, MAX6724UTSDD3+T offers push-pull drive for direct CMOS interfacing but removes flexibility of external pullup configuration, while TPS3808G33DBVR reduces complexity and cost at the expense of triple-supply capability and watchdog supervision.

Availability

MAX6723UTSDD3+T is available at Aetrix Electronics and suitable for telecom infrastructure, industrial control, and portable medical equipment requiring stable component supply, long-lifecycle support, and guaranteed lead-free compliance.

Supply support for MAX6723UTSDD3+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 and mixed-signal ICs for power, sensing, and connectivity applications, with emphasis on reliability and integration.

The MAX6715–MAX6729 family delivers compact, ultra-low-power supervisory solutions for multivoltage embedded systems where simultaneous monitoring of primary, secondary, and auxiliary rails is essential for safe boot and runtime integrity.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6723UTSDD3+T?

The MAX6723UTSDD3+T has a factory-trimmed VCC1 reset threshold of 4.625V, with a tolerance of ±125mV (min 4.500V, max 4.750V) over temperature. This value is encoded in the "TS" suffix per Maxim's Reset Voltage Threshold Suffix Guide and is verified in the Electrical Characteristics table under VTH1 parameter.

Does the MAX6723UTSDD3+T support power-fail detection?

No, the MAX6723UTSDD3+T does not include power-fail input (PFI) or power-fail output (PFO) functionality. Per the Selector Guide, only MAX6728/MAX6729 variants support PFI/PFO; MAX6723 is designated for triple-voltage monitoring with RSTIN, MR, and WDI-but no power-fail comparator.

What is the function of pin 5 (WDI) on the MAX6723UTSDD3+T?

Pin 5 (WDI) on the MAX6723UTSDD3+T is the watchdog input that monitors microprocessor activity. It triggers a reset if held static (high or low) beyond the timeout period-35s minimum after power-up or reset, then 1.12s minimum during normal operation. A rising or falling edge clears the watchdog timer.

Can the MAX6723UTSDD3+T monitor a 1.2V supply as the third voltage?

Yes, the MAX6723UTSDD3+T can monitor a 1.2V supply via the RSTIN pin using an external resistor divider. With its 626.5mV internal reference, a divider ratio of R1/R2 = (1.2V / 0.6265V) − 1 ≈ 0.914 enables precise 1.2V trip point, and low RSTIN input current (<25nA) ensures minimal loading.

Is the reset output of the MAX6723UTSDD3+T push-pull or open-drain?

The MAX6723UTSDD3+T features an open-drain RST output (pin 1), as confirmed by the Selector Guide and Pin Description. It requires an external pullup resistor to VCC1 and is not capable of actively driving high; this configuration supports wired-OR reset buses and level translation across voltage domains.