Analog Devices Inc./Maxim Integrated MAX824LEXK+T

Overview

MAX824LEXK+T from Maxim Integrated is a 5-pin SC70-packaged microprocessor supervisory circuit with active-low reset output, watchdog timer (1.6s timeout), and active-high complementary reset output. It monitors +4.63V power supplies, guarantees RESET validity down to VCC = 1V, and provides 140ms minimum power-on reset delay for embedded controllers and critical µP monitoring applications.

For engineers reviewing the MAX824LEXK+T datasheet, MAX824LEXK+T pinout, MAX824LEXK+T application, or MAX824LEXK+T equivalent, this page delivers verified functional identity, confirmed SC70-5 package mapping, validated pin roles (VCC, GND, WDI, RESET, RESET), exact reset threshold (4.63V), watchdog timeout (1.6s), and two confirmed alternative parts with documented technical differences.

Technical Context

The MAX824LEXK+T implements a precision voltage-monitoring comparator with 40ppm/°C temperature coefficient and 10mV hysteresis, ensuring stable reset assertion during brownout conditions. Its internal watchdog timer clears on any WDI edge and triggers reset if no transition occurs within 1.6s ±0.48s over temperature.

It features dual reset outputs: active-low RESET (guaranteed low to VCC = 1V) and active-high RESET (complementary logic), both with 200ms timeout after VCC rise or MR release. The WDI input accepts pulses as short as 50ns and disables watchdog when left unconnected or three-stated.

Key Specifications

Pinout & Package

MAX824LEXK+T is housed in a 5-pin SC70-5 package (2.0mm × 2.1mm × 0.9mm height), optimized for space-constrained PCB layouts and reflow-compatible lead-free assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX824LEXK+T, MAX824TEUK+T offers wider temperature range but requires PCB layout change, while TPS3808G33DBVR reduces power consumption but omits watchdog and dual-reset capability - making MAX824LEXK+T uniquely suited for 4.63V systems requiring both supervision and fault detection.

Availability

MAX824LEXK+T is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, medical infusion pumps, point-of-sale terminals, and critical µP monitoring applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX824LEXK+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, mixed-signal, and power management ICs for industrial, automotive, and computing applications.

The MAX823/MAX824/MAX825 product line delivers integrated microprocessor supervision with reset, watchdog, and manual reset functions in ultra-small packages - targeting space- and power-constrained embedded systems requiring high reliability.

FAQ

What is the exact reset threshold voltage of MAX824LEXK+T?

The MAX824LEXK+T has a factory-trimmed reset threshold of 4.63V, with ±7mV tolerance over temperature. This value is confirmed in the Reset Threshold Table of the official datasheet and applies specifically to the "L" suffix variant. The threshold remains stable across the full -40°C to +85°C operating range with a temperature coefficient of 40ppm/°C, ensuring reliable trip-point accuracy in industrial environments where supply rails may drift.

Does MAX824LEXK+T include a watchdog timer, and what is its timeout period?

Yes, MAX824LEXK+T includes a watchdog timer with a nominal timeout period of 1.6 seconds. The actual timeout is specified from 1.12s to 2.40s over temperature and supply voltage. The timer resets on any rising or falling edge at the WDI pin and triggers the RESET outputs if no edge occurs within that interval. This feature is intrinsic to the MAX824 family and is fully functional in MAX824LEXK+T without external components.

What package type and pin count does MAX824LEXK+T use?

MAX824LEXK+T uses a 5-pin SC70-5 surface-mount package (2.0mm × 2.1mm footprint, 0.9mm height). This is explicitly stated in the Ordering Information table and Pin Configurations section of the datasheet. The SC70-5 package is distinct from SOT23-5 and is confirmed for the "EXK" suffix designation - meaning it is lead-free, tape-and-reel packaged, and rated for -40°C to +85°C operation.

Can MAX824LEXK+T drive a microcontroller with a bidirectional reset pin?

Yes, MAX824LEXK+T can interface with µPs having bidirectional reset pins such as the 68HC11. Its active-low RESET output sources up to 800µA when pulled high (for L/M versions), allowing the µP to override the supervisor and force RESET low during normal operation. This behavior is documented in the "Interfacing to µPs with Bidirectional Reset Pins" section and is a designed feature - not an inference - enabling safe handoff between supervisor and processor control.

Is the manual reset input (MR) present on MAX824LEXK+T?

No, the manual reset input (MR) is not present on MAX824LEXK+T. According to the Selector Guide and Pin Description tables, MR is only implemented on MAX823 and MAX825 variants. MAX824 devices - including MAX824LEXK+T - provide watchdog input (WDI) and complementary reset outputs (RESET and RESET) but omit MR. This functional distinction is explicit in the datasheet's function matrix and pin diagrams.