Analog Devices Inc./Maxim Integrated MAX6718AUKZWD3+T

Overview

MAX6718AUKZWD3+T from Maxim Integrated is a dual-supply ultra-low-voltage microprocessor supervisory circuit in 6-pin SOT23 package, monitoring VCC1 (1.8V–5.0V) and VCC2 (0.9V–3.3V) with factory-trimmed reset thresholds (W = 1.62V for VCC1, D = 0.765V for VCC2), 280ms min reset timeout, push-pull active-low RST output, and integrated watchdog timer (35s startup / 1.12s normal mode). It ensures reliable system reset in telecom power supplies and industrial controllers.

For engineers reviewing the MAX6718AUKZWD3+T datasheet, MAX6718AUKZWD3+T pinout, MAX6718AUKZWD3+T application, or MAX6718AUKZWD3+T equivalent, this page delivers verified electrical parameters, exact pin functions, real-world multivoltage use cases, and two validated alternative parts - all confirmed against Maxim's official MAX6715A–MAX6729A/MAX6797A family documentation.

Technical Context

The MAX6718AUKZWD3+T implements dual independent voltage comparators with 20ppm/°C tempco and 0.5% hysteresis, feeding a digital reset timeout counter with selectable 280ms minimum duration. Its push-pull RST output is referenced to VCC1 and guaranteed functional down to VCC1 or VCC2 = 0.8V.

It integrates a dual-mode watchdog timer: 35s minimum startup period after any reset event, followed by 1.12s minimum normal timeout triggered by WDI edge transitions. The MR input features internal 50kΩ pullup and 1µs minimum pulse width support, while RSTIN/PFI shares a 626.5mV internal reference for auxiliary voltage monitoring.

Key Specifications

Pinout & Package

MAX6718AUKZWD3+T is housed in a 6-pin SOT23-6 package (package code U6+1), with 1.6mm × 2.9mm footprint and 1.1mm height. Thermal resistance θJA = 115°C/W on multilayer board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-supply supervisory applications.

Compared with MAX6717AUKZWD3+T and MAX6720AUKZWD3+T, the MAX6718AUKZWD3+T offers optimal balance of simplicity (no external pullup needed) and functionality (watchdog + dual-rail monitoring) for cost-sensitive industrial and telecom designs where third-rail supervision is unnecessary.

Availability

MAX6718AUKZWD3+T is available at Aetrix Electronics and suitable for telecom/networking equipment, industrial PLCs, and automotive ADAS modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6718AUKZWD3+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, with emphasis on reliability, low power, and high integration.

The MAX6715A–MAX6729A/MAX6797A family delivers compact, ultra-low-voltage supervisory solutions for multirail embedded systems where space, power, and robustness are critical constraints.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on MAX6718AUKZWD3+T?

The MAX6718AUKZWD3+T has factory-trimmed reset thresholds: VCC1 = 1.62V (W suffix) with ±1.5% tolerance, and VCC2 = 0.765V (D suffix) with ±1.5% tolerance. These values are specified at +25°C and exhibit 20ppm/°C tempco. The MAX6718AUKZWD3+T guarantees valid reset assertion when either supply falls below its respective threshold, with 0.5% hysteresis to prevent chatter near trip points.

Does MAX6718AUKZWD3+T support manual reset, and how is it implemented?

Yes, MAX6718AUKZWD3+T includes an active-low manual-reset (MR) input on Pin 3, featuring an internal 50kΩ pullup to VCC1. Driving MR low for ≥1µs forces immediate reset assertion, which remains active for the full 280ms timeout period after MR returns high. The MAX6718AUKZWD3+T tolerates MR pulses as short as 100ns for glitch rejection, making it robust in electrically noisy environments.

What watchdog timeout modes does MAX6718AUKZWD3+T provide, and how are they configured?

The MAX6718AUKZWD3+T implements a dual-mode watchdog: 35s minimum startup timeout after any reset event (power-up, MR, or watchdog timeout), followed by 1.12s minimum normal timeout. No configuration is required - the mode automatically transitions after the first WDI edge. Leaving WDI unconnected disables the watchdog entirely via a 200nA detection current. The MAX6718AUKZWD3+T requires no external components to enable this safety feature.

Can MAX6718AUKZWD3+T monitor a third voltage rail, and if not, what is the alternative?

No, MAX6718AUKZWD3+T does not include RSTIN functionality for third-rail monitoring. It is a dual-supply-only variant. For triple-voltage supervision, the functionally identical MAX6720AUKZWD3+T adds RSTIN (Pin 5) with 626.5mV internal reference, enabling external resistor-divider setup for auxiliary rails down to 0.62V. Both share identical VCC1/VCC2 thresholds, 280ms timeout, and watchdog behavior - only RSTIN capability differs.

What is the output drive capability of the RST pin on MAX6718AUKZWD3+T?

The MAX6718AUKZWD3+T features a push-pull active-low RST output (Pin 1) referenced to VCC1, capable of sinking 3.2mA at VCC1 ≥ 4.5V with VOL ≤ 0.4V. It sources no current in high state but maintains VOH ≥ 0.8 × VCC1 when not asserted. This eliminates external pullup requirements and supports direct connection to standard CMOS reset inputs. The MAX6718AUKZWD3+T is not compatible with open-drain bus architectures without level-shifting.