Analog Devices Inc./Maxim Integrated MAX6734KAVDD3+T

Overview

MAX6734KAVDD3+T from Maxim Integrated is a triple-voltage microprocessor supervisor IC with independent watchdog timer, monitoring VCC1 (primary), VCC2 (secondary), and RSTIN (adjustable) supply rails. It features factory-set reset thresholds (VCC1 = +3.075 V, VCC2 = +2.313 V), 140–280 ms reset timeout (D3 suffix), open-drain RST/WDO outputs, and manual reset input - used in multivoltage embedded systems requiring reliable power-on reset and lockup recovery.

For engineers reviewing the MAX6734KAVDD3+T datasheet, MAX6734KAVDD3+T pinout, MAX6734KAVDD3+T application, or MAX6734KAVDD3+T equivalent, key selection criteria include dual fixed-voltage supervision plus adjustable third-rail monitoring, 140–280 ms reset timeout, -40°C to +85°C operation, SOT23-8 package, and compatibility with low-power μP-based telecom, industrial, and portable equipment.

Technical Context

The MAX6734KAVDD3+T integrates three independent voltage monitors: VCC1 and VCC2 use factory-trimmed bandgap references (±1.5% threshold accuracy), while RSTIN employs a precise 626 mV internal reference for externally scaled rail monitoring. Its dual-mode watchdog timer provides a 35 s startup delay followed by 1.12 s normal timeout, ensuring robust system initialization and runtime fault detection.

All reset assertions - from VCC1/VCC2 undervoltage, RSTIN threshold breach, or MR activation - trigger a guaranteed-valid active-low open-drain RST output down to VCC1 or VCC2 ≥ +0.8 V. The device draws only 14 µA typical supply current at +3.6 V and operates across the full industrial temperature range without external components beyond pullups.

Key Specifications

Pinout & Package

SOT23-8 package: 2.9 mm × 2.8 mm, 0.95 mm height, gull-wing leads, RoHS-compliant lead(Pb)-free (+T) construction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6734KAVDD3+T, MAX6734KATGD3+T shifts threshold coverage downward for low-voltage SoCs, while MAX6735KAVDD3+T retains identical supervision specs but replaces open-drain outputs with push-pull - offering direct-drive capability at the cost of added routing constraints.

Availability

MAX6734KAVDD3+T is available at Aetrix Electronics and suitable for telecom infrastructure, industrial automation, and portable medical equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6734KAVDD3+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 high-reliability industrial and communications solutions.

The MAX6730–MAX6735 family delivers integrated triple-supply supervision and watchdog functionality specifically for space-constrained, multirail embedded systems demanding deterministic reset behavior and robust lockup recovery.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6734KAVDD3+T?

The MAX6734KAVDD3+T has factory-set VCC1 reset threshold of +3.075 V (falling edge) and VCC2 reset threshold of +2.313 V (falling edge), per the "VD" suffix in its ordering code. These values are trimmed during production and guaranteed over -40°C to +85°C with ±1.5% accuracy. The MAX6734KAVDD3+T uses these fixed thresholds to supervise common +3.3 V and +2.5 V rails without external components.

Does the MAX6734KAVDD3+T support an adjustable third voltage monitor, and how is it implemented?

Yes, the MAX6734KAVDD3+T includes an adjustable RSTIN input with a precise +626 mV internal reference. To monitor voltages above +0.63 V, connect a resistive divider between the target rail and ground, feeding the midpoint to RSTIN. The MAX6734KAVDD3+T asserts reset when the divided voltage falls below +626 mV - enabling supervision of custom or nonstandard supply rails with no additional ICs.

What are the watchdog timer timing parameters for the MAX6734KAVDD3+T?

The MAX6734KAVDD3+T features a dual-mode watchdog timer: a minimum 35 s startup delay after reset (to allow full system initialization), followed by a normal-mode timeout of 1.12 s (min). A rising or falling edge on WDI resets the timer; absence of edges longer than the active timeout causes WDO to assert low. This architecture ensures safe boot and rapid fault response - both timing parameters are process- and temperature-stable.

Is the MAX6734KAVDD3+T pin-compatible with other devices in the MAX6730–MAX6735 family?

The MAX6734KAVDD3+T uses the SOT23-8 package and shares identical pinout with MAX6734 and MAX6735 variants (e.g., MAX6734KATGD3+T, MAX6735KAVDD3+T). However, it is not pin-compatible with the 6-pin MAX6730–MAX6733 series. All SOT23-8 versions maintain consistent RST, GND, WDO, VCC1, RSTIN, WDI, MR, and VCC2 assignments - enabling drop-in replacement within the 8-pin subgroup when thresholds and output type match.

What is the supply current consumption of the MAX6734KAVDD3+T, and how does it vary with voltage?

The MAX6734KAVDD3+T draws 14 µA typical supply current at +3.6 V (ICC1 + ICC2), with total current remaining below 39 µA across its full 0.8 V to 5.5 V operating range. At lower VCC1 voltages (e.g., +1.8 V), ICC1 drops to ~10 µA and ICC2 to ~4 µA - making the MAX6734KAVDD3+T suitable for battery-operated systems where quiescent power directly impacts runtime.