Analog Devices Inc./Maxim Integrated MAX6732UTLTD3

Overview

MAX6732UTLTD3 from Maxim Integrated is a dual-voltage microprocessor supervisor IC with independent watchdog output, monitoring VCC1 at +4.625V and VCC2 at +3.075V, featuring 210ms reset timeout, open-drain RST/WDO outputs, and operation from -40°C to +85°C. It ensures reliable system boot and runtime supervision in multivoltage embedded systems such as telecom power management and industrial controllers.

For engineers reviewing the MAX6732UTLTD3 datasheet, MAX6732UTLTD3 pinout, MAX6732UTLTD3 application, or MAX6732UTLTD3 equivalent, key selection factors include confirmed dual-threshold detection accuracy, guaranteed reset validity down to VCC = +0.8V, watchdog startup delay (35s min), low 14µA typical supply current, and SOT23-6 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6732UTLTD3 implements two independent voltage comparators with factory-set thresholds (+4.625V for VCC1, +3.075V for VCC2), hysteresis of 0.5% of VTH, and 45µs VCC-to-RST propagation delay. Its reset logic asserts active-low RST when either supply falls below its threshold and holds for the full 140–280ms timeout window.

It integrates a dual-mode watchdog timer: initial mode (≥35s after reset) accommodates system initialization, then transitions to normal mode (≥1.12s timeout) upon first WDI edge detection. The open-drain WDO output requires external pullup and asserts low on WDI stall or undervoltage lockout.

Key Specifications

Pinout & Package

MAX6732UTLTD3 is housed in a 6-pin SOT23-6 package (JEDEC MO-178), measuring 2.9mm × 1.6mm × 1.1mm, with gull-wing leads and lead-free finish (RoHS compliant).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6732UTLTD3, MAX6732UTSYD3-T offers matched functionality with adjusted thresholds for alternate rail schemes, while TPS3808G33DBVR trades dual monitoring and watchdog independence for significantly lower supply current in single-rail designs.

Availability

MAX6732UTLTD3 is available at Aetrix Electronics and suitable for telecom infrastructure, industrial control, and medical diagnostic equipment requiring stable component supply with guaranteed long-term lifecycle support.

Supply support for MAX6732UTLTD3 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.

The MAX6730–MAX6735 family delivers integrated dual/triple-voltage supervision with independent watchdog capability for embedded systems requiring high-reliability power sequencing and runtime fault detection.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6732UTLTD3?

The MAX6732UTLTD3 has a factory-set VCC1 reset threshold of +4.625V (±125mV) and VCC2 threshold of +3.075V (±75mV), as defined by the "LT" suffix in its part number. These values are guaranteed over the full -40°C to +85°C operating range with 0.5% hysteresis referenced to typical VTH, ensuring stable trip points across temperature and supply variation. The MAX6732UTLTD3 uses internal precision references-not external resistor dividers-to achieve this accuracy.

Does the MAX6732UTLTD3 support manual reset functionality?

No, the MAX6732UTLTD3 does not include a manual reset (MR) input. Per the selector guide and pin description, only MAX6730/MAX6731/MAX6734/MAX6735 variants feature MR; MAX6732/MAX6733 are dual-supply supervisors without MR. The MAX6732UTLTD3 relies solely on VCC1/VCC2 monitoring and watchdog input (WDI) for reset initiation. Its RST output asserts only on undervoltage or WDI timeout events-not on external button press.

What is the watchdog timeout behavior of the MAX6732UTLTD3 during system startup?

The MAX6732UTLTD3 implements a dual-mode watchdog: after any reset event (power-up, brownout, or WDI timeout), it enters an initial watchdog mode with ≥35s timeout to allow full system initialization. Upon detecting the first valid WDI edge, it switches to normal mode with ≥1.12s timeout. This prevents premature watchdog expiration during boot. The MAX6732UTLTD3's WDO output remains deasserted until timeout occurs, and its open-drain structure requires an external pullup resistor for proper logic-level translation.

Can the MAX6732UTLTD3 monitor voltages below 3.075V on its VCC2 pin?

No-the VCC2 pin of the MAX6732UTLTD3 is factory-trimmed to +3.075V and cannot be adjusted. It monitors only that fixed threshold. To supervise lower voltages (e.g., 1.8V or 1.2V), you would need a different variant like MAX6732UTRVD3-T (VCC2 = +2.625V) or MAX6732UTZWD3-T (VCC2 = +2.313V), or use the MAX6734/MAX6735 series with RSTIN for adjustable monitoring. The MAX6732UTLTD3's VCC2 input accepts supply voltages from +0.8V to +5.5V but triggers reset only when falling below +3.075V.

What package type and footprint does the MAX6732UTLTD3 use?

The MAX6732UTLTD3 uses a 6-pin SOT23-6 package (JEDEC MO-178), with 0.95mm pin pitch, 2.9mm × 1.6mm body size, and gull-wing leads. It is RoHS-compliant and available in lead-free form (suffix "+T"). This compact footprint matches standard SOT23-6 land patterns used for voltage supervisors and regulators, enabling drop-in replacement in space-constrained designs where dual-rail monitoring is required without adding a second IC.