Analog Devices Inc./Maxim Integrated MAX6723UTSDD3+

Overview

MAX6723UTSDD3+ from Maxim Integrated is a triple-voltage microprocessor supervisory circuit in SOT23-6 package, monitoring VCC1 (primary), VCC2 (secondary), and RSTIN (adjustable third supply) with factory-trimmed thresholds of 3.075V (VTH1), 2.925V (VTH2), and 626.5mV reference for RSTIN. It asserts an active-low open-drain reset output with 210ms minimum timeout and guarantees valid reset operation down to VCC1 or VCC2 = 0.8V. Used in multivoltage embedded systems requiring reliable power-up sequencing and brownout protection.

For engineers reviewing the MAX6723UTSDD3+ datasheet, MAX6723UTSDD3+ pinout, MAX6723UTSDD3+ application, or MAX6723UTSDD3+ equivalent, key selection criteria include dual/third-supply monitoring capability, 210ms reset timeout, open-drain RST output, watchdog-free configuration, and guaranteed reset validity at ultra-low supply voltages (0.8V).

Technical Context

The MAX6723UTSDD3+ implements independent voltage comparators for VCC1 and VCC2, plus a high-impedance RSTIN input referenced to a 626.5mV internal bandgap. Reset assertion occurs when any monitored voltage falls below its threshold, and reset remains asserted for a fixed 210ms minimum timeout after all supplies recover.

It features no watchdog timer or power-fail comparator-confirmed by Selector Guide and Pin Description-and uses an internal 50kΩ pullup on MR. The open-drain RST output requires an external pullup and is referenced to VCC1, supporting bidirectional µP reset interfaces without contention.

Key Specifications

Pinout & Package

MAX6723UTSDD3+ is housed in a 6-pin SOT23-6 package with gull-wing leads, 1.27mm pitch, and JEDEC MO-178AC footprint. Thermal performance supports continuous operation at ambient up to +85°C with standard PCB copper pour.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6724UTSDD3+, the MAX6723UTSDD3+ offers open-drain flexibility for shared reset buses but requires an external pullup; versus TPS3808G33DBVR, it adds critical RSTIN-based third-rail monitoring at the cost of slightly higher design complexity.

Availability

MAX6723UTSDD3+ is available at Aetrix Electronics and suitable for industrial PLC controllers, telecom line cards, and medical handhelds requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.

Supply support for MAX6723UTSDD3+ 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 demanding industrial, automotive, and communications applications, with emphasis on reliability, integration, and low-power operation.

The MAX6715–MAX6729 family delivers compact, ultra-low-voltage supervisory solutions targeting multirail embedded systems where space, power, and supply robustness are critical constraints.

FAQ

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

The MAX6723UTSDD3+ has a factory-trimmed VCC1 reset threshold of 3.075V (typical), with min/max values of 3.000V and 3.150V across temperature and process variation. This value is encoded in the 'S' suffix per the Reset Voltage Threshold Suffix Guide and applies specifically to the MAX6723UTSDD3+ variant.

Does the MAX6723UTSDD3+ include a watchdog timer function?

No, the MAX6723UTSDD3+ does not include a watchdog timer. Per the Selector Guide and Functional Diagram, MAX6723 is explicitly listed without WDI support. Watchdog capability is only present in MAX6721–MAX6729 variants with 'W' in the ordering code - the MAX6723UTSDD3+ is a dedicated triple-supply supervisor without watchdog logic.

What is the function of the RSTIN pin on the MAX6723UTSDD3+?

The RSTIN pin on the MAX6723UTSDD3+ serves as a high-impedance input for monitoring a third supply voltage using an external resistor divider. It compares the applied voltage against a 626.5mV internal reference, enabling adjustable reset thresholds down to 0.62V. When RSTIN falls below this reference, the device asserts the RST output.

What package type and pin count does the MAX6723UTSDD3+ use?

The MAX6723UTSDD3+ uses a 6-pin SOT23-6 package (JEDEC MO-178AC), with gull-wing leads, 1.27mm pitch, and standard thermal pad layout. This matches the pin configuration shown in the Pin Description table for MAX6723/MAX6724 variants, confirming pins 1–6 as RST, GND, MR, VCC2, VCC1, and RSTIN respectively.

Is the MAX6723UTSDD3+ compatible with bidirectional microprocessor reset pins?

Yes, the MAX6723UTSDD3+ is compatible with bidirectional µP reset pins due to its open-drain RST output. This allows safe connection to µPs that drive reset low during normal operation and sample it high during boot - no external series resistor is required unless noise immunity is critical, as confirmed in the Applications Information section.