Analog Devices Inc./Maxim Integrated MAX6734KASYD3-T

Overview

MAX6734KASYD3-T from Maxim Integrated is a triple-voltage microprocessor supervisor IC with independent watchdog output, monitoring VCC1 (+2.925V threshold), VCC2 (+2.188V threshold), and an adjustable RSTIN input (626mV reference). It features open-drain RST and WDO outputs, manual reset input (MR), and a 210ms minimum reset timeout period. Used in multivoltage embedded systems to ensure reliable power-on initialization and runtime fault detection.

For engineers reviewing the MAX6734KASYD3-T datasheet, MAX6734KASYD3-T pinout, MAX6734KASYD3-T application, or MAX6734KASYD3-T equivalent, this page delivers verified electrical specs, SOT23-8 package details, dual-mode watchdog timing (35s startup / 1.12s normal), reset threshold hysteresis (0.5%), and confirmed compatibility with telecom, industrial, and portable equipment designs requiring stable dual-supply monitoring and fail-safe reset assertion.

Technical Context

The MAX6734KASYD3-T implements three independent voltage monitors: a factory-set +2.925V threshold on VCC1, +2.188V on VCC2, and a precision 626mV internal reference for the high-impedance RSTIN comparator-enabling third-supply monitoring via external resistive divider. Its reset logic asserts active-low RST when any monitored voltage falls below its threshold or MR is pulled low.

It integrates a dual-mode watchdog timer: a 35s (min) initial startup delay after reset ensures full system initialization, followed by a 1.12s (min) normal-mode timeout triggered by missing WDI edges. Both RST and WDO outputs are open-drain, requiring external pullups, and operate reliably down to VCC1/VCC2 = +0.8V.

Key Specifications

Pinout & Package

MAX6734KASYD3-T is housed in an 8-pin SOT23-8 package (JEDEC MO-178AA), measuring 2.9mm × 1.6mm × 1.1mm, with gull-wing leads and RoHS-compliant lead-free finish (+T suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6734KASYD3-T, MAX6734KATZD3-T offers higher VCC2 threshold precision for 2.5V rails but sacrifices margin for 2.2V systems, while TPS3808G33DBVR reduces cost and size at the expense of monitoring flexibility and system-level fault coverage.

Availability

MAX6734KASYD3-T is available at Aetrix Electronics and suitable for telecom infrastructure, industrial automation, and portable medical devices requiring stable component supply, long-lifecycle support, and guaranteed -40°C to +85°C operation.

Supply support for MAX6734KASYD3-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 demanding industrial, automotive, and communications applications.

The MAX6730–MAX6735 family targets robust power-supply supervision in multivoltage embedded systems-emphasizing glitch immunity, low-power operation, and flexible reset/wdog timing for μP-based equipment.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6734KASYD3-T?

The MAX6734KASYD3-T has a factory-set VCC1 reset threshold of +2.925V (falling edge), corresponding to the "SY" suffix in the Reset Voltage Threshold Suffix Guide. This value is guaranteed over -40°C to +85°C with ±1.5% tolerance and 20ppm/°C tempco. The threshold is used to monitor +3.3V rails during brownout conditions, and the MAX6734KASYD3-T asserts RST low when VCC1 drops below this level.

Does the MAX6734KASYD3-T support monitoring a third voltage, and how is it configured?

Yes, the MAX6734KASYD3-T supports third-voltage monitoring via its RSTIN pin, which features a precise 626mV internal reference. To monitor voltages above 626mV, connect a resistive divider between the target supply and GND, with the midpoint fed to RSTIN. The MAX6734KASYD3-T asserts RST when the divided voltage falls below 626mV. RSTIN draws only ±25nA, enabling high-resistance dividers for minimal power loss.

What are the watchdog timeout periods for the MAX6734KASYD3-T?

The MAX6734KASYD3-T features a dual-mode watchdog: a minimum 35s startup delay after reset (to allow full system initialization), followed by a minimum 1.12s normal-mode timeout. The watchdog triggers if no rising or falling edge occurs on WDI within these intervals. Both timeouts are factory-trimmed and stable over temperature-no external components are needed to set or adjust them in the MAX6734KASYD3-T.

Is the MAX6734KASYD3-T compatible with bidirectional microprocessor reset pins?

Yes, but with caution: the MAX6734KASYD3-T's open-drain RST output is inherently compatible with bidirectional μP reset I/O ports. However, to prevent logic contention during μP-driven reset assertion, a 10kΩ series resistor should be placed between RST and the μP pin-as documented in the Applications Information section. This ensures safe bidirectional operation without damaging either device, and the MAX6734KASYD3-T remains fully functional in such configurations.

What package type and RoHS status does the MAX6734KASYD3-T use?

The MAX6734KASYD3-T uses an 8-pin SOT23-8 package (outline 21-0078) with gull-wing leads and a lead-free, RoHS-compliant finish indicated by the "+T" suffix. Its dimensions are 2.9mm × 1.6mm × 1.1mm, and thermal resistance is θJA = 180°C/W (JEDEC 4-layer board). The package is qualified for reflow soldering at +260°C and supports automated assembly without special handling-standard for the MAX6734KASYD3-T.