Analog Devices Inc./Maxim Integrated MAX825TEXK

Overview

MAX825TEXK from Maxim Integrated is a 5-pin microprocessor supervisory circuit with manual reset input and complementary active-high reset output, designed for precision monitoring of +3.08V power supplies in embedded systems. It guarantees valid reset assertion down to VCC = 1V, features 140ms minimum power-on reset timeout, 2µA supply current (SC70 package), and immunity to fast VCC transients. Used in portable battery-powered equipment requiring reliable brownout protection.

For engineers reviewing the MAX825TEXK datasheet, MAX825TEXK pinout, MAX825TEXK application, or MAX825TEXK equivalent, this page delivers verified functional identity, exact SC70-5 pin mapping, confirmed reset threshold (3.08V), manual reset timing (500ns MR-to-reset delay), and validated alternative options for critical µP monitoring designs.

Technical Context

The MAX825TEXK implements a precision voltage comparator with 5mV hysteresis and 40ppm/°C temperature coefficient to detect VCC drops below 3.08V. Its internal reset timer ensures 140–280ms reset pulse width after power-up or brownout recovery.

It integrates a manual reset input (MR) with 52kΩ internal pullup, 1.0µs minimum pulse width support, and 100ns noise immunity-enabling direct interface to CMOS logic or momentary switches without external components.

Key Specifications

Pinout & Package

MAX825TEXK is packaged in a 5-pin SC70-5 (SOT-457) surface-mount package measuring 2.0mm × 2.1mm × 0.95mm, optimized for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX825TEXK, MAX825SEUK-T offers identical functionality in a thermally robust SOT23 package for harsh environments, while TPS3808G30DBVR trades dual-output flexibility for marginally lower quiescent current-making MAX825TEXK optimal for space-constrained designs needing both reset polarities without external logic.

Availability

MAX825TEXK is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, automotive body control units, and smart energy meters requiring stable component supply across industrial temperature ranges.

Supply support for MAX825TEXK 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 industrial, automotive, and computing applications, with emphasis on power management and system-level reliability.

The MAX823/MAX824/MAX825 family was engineered specifically for microprocessor supervision in resource-constrained embedded systems-delivering integrated reset, manual reset, and watchdog functions in minimal 5-pin packages.

FAQ

What is the exact reset threshold voltage for MAX825TEXK?

The MAX825TEXK has a factory-trimmed reset threshold of 3.08V, specified as 3.04V to 3.11V over the full -40°C to +85°C temperature range. This value is confirmed in the Reset Threshold Table of the official datasheet and applies specifically to the "T" suffix variant in SC70 packaging. The MAX825TEXK uses this precise threshold to monitor +3.3V power rails without requiring external resistive dividers.

Does MAX825TEXK provide both active-high and active-low reset outputs?

Yes, the MAX825TEXK provides dual complementary reset outputs: pin 3 is active-high RESET and pin 4 is active-low RESET. Both outputs respond identically to VCC falling below 3.08V or MR being pulled low, ensuring synchronized reset assertion across multiple device domains. This dual-output capability is intrinsic to the MAX825 variant and is explicitly documented in the Pin Description and Selector Guide sections of the MAX825TEXK datasheet.

What is the supply current of MAX825TEXK and under what conditions is it measured?

The MAX825TEXK draws 2µA typical supply current when measured in SC70 package with MR unconnected and at TA = +25°C, per the Electrical Characteristics table. This ultra-low quiescent current is maintained across the full operating temperature range (-40°C to +85°C) and enables multi-year battery life in always-on portable equipment. The MAX825TEXK achieves this efficiency through BiCMOS process optimization and internal biasing that scales with VCC.

Can MAX825TEXK operate reliably during VCC brownout events down to 1V?

Yes, the MAX825TEXK guarantees valid reset output states (both RESET and RESET) for VCC as low as 1V, as explicitly stated in the General Description and Electrical Characteristics sections. This ensures deterministic behavior during deep brownout or backup power transitions-critical for preserving register state and preventing partial writes in nonvolatile memory. The MAX825TEXK maintains internal logic integrity and comparator accuracy even at this minimum supply voltage.

What package type and pin count does MAX825TEXK use, and is it lead-free?

The MAX825TEXK uses a 5-pin SC70-5 (SOT-457) package with 0.65mm lead pitch and is available in lead-free (RoHS-compliant) form. The "-T" suffix denotes tape-and-reel packaging, and lead-free ordering requires replacing "-T" with "+T". This compact 2.0mm × 2.1mm footprint is ideal for space-constrained PCB layouts in portable electronics, and the package meets IPC/JEDEC J-STD-020 moisture sensitivity level 1 for standard reflow processing.