Analog Devices Inc./Maxim Integrated MAX6824ZUK+

Overview

MAX6824ZUK+ from Maxim Integrated is a low-voltage microprocessor supervisory IC in 5-pin SOT23 package, providing dual reset outputs (active-low push-pull RESET and active-high push-pull RESET), 1.6s watchdog timeout, 2.32V reset threshold, and guaranteed reset validity down to VCC = +1.0V. It monitors power rails in portable/battery-powered equipment and embedded controllers where reliable brownout detection and code-execution monitoring are critical.

For engineers reviewing the MAX6824ZUK+ datasheet, MAX6824ZUK+ pinout, MAX6824ZUK+ application, or MAX6824ZUK+ equivalent, this page delivers verified pin functions, exact reset timing behavior, watchdog interaction logic, and real-world substitution guidance for industrial and battery-operated systems.

Technical Context

The MAX6824ZUK+ integrates voltage monitoring, watchdog timer, and dual-reset output generation in a single BiCMOS device. Its reset threshold is factory-trimmed to 2.32V (±3% over –40°C to +125°C), with 60ppm/°C temperature coefficient and 2×VTH hysteresis. The internal 140ms minimum reset timeout ensures stable µP initialization after VCC recovery.

Watchdog operation relies on edge-triggered WDI input detection (50ns pulse width minimum); the 1.6s timeout period is guaranteed across full temperature range. Unlike MAX6821–MAX6823, MAX6824ZUK+ omits manual reset input but retains watchdog functionality and dual push-pull reset outputs - enabling simultaneous control of active-low and active-high reset domains without external logic.

Key Specifications

Pinout & Package

MAX6824ZUK+ uses a 5-pin SOT23-5 package (outline U5-1, land pattern 21-0057), RoHS-compliant with lead-free termination ("+" suffix). Pin 1 is RESET (active-low push-pull), Pin 2 is GND, Pin 3 is WDI, Pin 4 is RESET (active-high push-pull), and Pin 5 is VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6824ZUK+, MAX6823ZUK+ adds manual reset but removes active-high RESET and simplifies watchdog interface, while MAX6316LUK33+T reduces feature set to basic voltage monitoring only - making MAX6824ZUK+ optimal for systems needing coordinated dual-reset signaling and autonomous µP execution verification.

Availability

MAX6824ZUK+ is available at Aetrix Electronics and suitable for portable/battery-powered equipment, embedded controllers, intelligent instruments, and critical µP monitoring applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6824ZUK+ 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, mixed-signal, and power management ICs for industrial, computing, communications, and consumer applications.

The MAX6821–MAX6825 family targets space-constrained, low-power embedded systems requiring integrated voltage supervision, watchdog protection, and flexible reset signaling - with MAX6824ZUK+ specifically optimized for dual-polarity reset control without manual reset overhead.

FAQ

What is the exact reset threshold voltage of the MAX6824ZUK+ and how is it specified?

The MAX6824ZUK+ has a factory-trimmed reset threshold of 2.32V, with ±3% tolerance over the full operating temperature range (–40°C to +125°C). This value is defined as the VCC voltage at which the RESET output transitions from inactive to active state during a falling VCC condition. The threshold exhibits 60ppm/°C temperature coefficient and includes 2×VTH hysteresis to prevent chatter near the trip point. Data sheet Table "VCC Reset Threshold (VCC Falling)" confirms this for suffix 'Z'.

Does the MAX6824ZUK+ include a manual reset input (MR)?

No, the MAX6824ZUK+ does not include a manual reset input. Unlike MAX6821–MAX6823 and MAX6825, the MAX6824 variant omits the MR pin to enable dual push-pull reset outputs (RESET and RESET) in the same 5-pin SOT23 package. Pin 3 is dedicated to WDI, and no internal pull-up or logic path exists for external MR assertion. This design choice prioritizes autonomous supervision over user-initiated reset capability.

How does the watchdog timer in the MAX6824ZUK+ interact with the reset outputs?

When the MAX6824ZUK+ watchdog timer expires due to lack of WDI edge activity within 1.6s, it simultaneously asserts both RESET (driven low) and RESET (driven high) for the full 140ms minimum reset timeout period. The timer clears immediately upon any rising or falling edge on WDI, and remains cleared while RESET is asserted. This ensures deterministic, synchronized reset signaling to multiple downstream logic domains during µP lockup events.

Can the MAX6824ZUK+ operate reliably at VCC = +1.0V?

Yes, the MAX6824ZUK+ guarantees correct RESET and RESET output states down to VCC = +1.0V, per the "Guaranteed Reset Valid to VCC = +1.0V" specification. While functional operation (e.g., watchdog timing accuracy or threshold precision) is only guaranteed above +1.2V, the reset outputs remain logically valid and electrically compliant - enabling fail-safe behavior during extreme brownout or battery depletion scenarios where other supervisors may release reset prematurely.

What are the absolute maximum ratings for the WDI pin on the MAX6824ZUK+?

The WDI pin on the MAX6824ZUK+ has an absolute maximum rating of –0.3V to (VCC + 0.3V), per the "Absolute Maximum Ratings" table. Input voltage levels must stay within 0.3×VCC (low) and 0.7×VCC (high) for reliable logic recognition, and the pin tolerates up to 160µA average input current when driven high. Exceeding these limits risks latch-up or permanent damage, especially during hot-plug or ESD events.