Analog Devices Inc./Maxim Integrated MAX603CPA

Overview

The MAX603CPA from Maxim Integrated is a 5V fixed-output, low-dropout linear regulator with P-channel MOSFET pass transistor, delivering up to 500mA output current, 320mV dropout at 5V/500mA, and 15μA typical quiescent current. It operates from 2.7V to 11.5V input and features shutdown mode (2μA), reverse-current protection, and thermal overload protection - ideal for battery-powered instrumentation and portable 5V systems.

For engineers reviewing the MAX603CPA datasheet, MAX603CPA pinout, MAX603CPA application, or MAX603CPA equivalent, key selection criteria include dropout performance under load, ultra-low IQ across temperature, fixed 5V output accuracy (±5%), shutdown threshold behavior, and SOIC/DIP package thermal management requirements.

Technical Context

The MAX603CPA implements a 1.20V bandgap reference, error amplifier, and MOSFET driver controlling an internal 500mA P-channel pass transistor. Its Dual Mode™ architecture selects between internal 5V feedback (SET = GND) and external adjustable configuration (SET = resistor divider), with dual-mode comparator threshold at 80mV.

Reverse-current protection activates when VIN falls 6–20mV below VOUT, switching substrate bias to limit reverse leakage to ≤10μA. Foldback current limiting provides 350mA short-circuit protection below 0.8V output and 1.2A limiting above 0.8V with sufficient VIN–VOUT margin.

Key Specifications

Pinout & Package

MAX603CPA uses an 8-pin plastic DIP (dual in-line package) with 0.3-inch body width and through-hole mounting. The package supports 727mW continuous power dissipation at +70°C ambient (derated 9.09mW/°C above).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout, low-IQ 5V regulator applications.

Compared with LM2940CT-5.0 and TPS76350DBVR, the MAX603CPA uniquely combines 500mA capability, 15μA IQ, reverse-current protection, and shutdown - making it the only option meeting all three requirements simultaneously in DIP-8 form factor.

Availability

MAX603CPA is available at Aetrix Electronics and suitable for portable instrumentation, battery-powered medical devices, and industrial data loggers requiring stable component supply with long-term lifecycle assurance.

Supply support for MAX603CPA 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 demanding industrial, medical, and communications applications.

The MAX603CPA belongs to Maxim's low-dropout linear regulator product line, engineered specifically for extended battery life and robust operation in portable and harsh-environment systems.

FAQ

What is the maximum continuous output current of the MAX603CPA?

The MAX603CPA delivers up to 500mA continuous output current under proper thermal conditions. At full load and elevated ambient temperatures, power dissipation must remain within the 727mW limit for the plastic DIP package - requiring adequate PCB copper area and airflow. Derating applies above +70°C ambient per the 9.09mW/°C specification.

Does the MAX603CPA require external capacitors, and what values are recommended?

Yes, the MAX603CPA requires external capacitors for stability and performance. Use ≥0.1μF (up to 10μF) on the IN pin for line-transient suppression, and ≥10μF on the OUT pin for load-transient response and stability across temperature and load. Capacitors smaller than 3.3μF risk oscillation, especially at high load currents.

How does the MAX603CPA achieve reverse-current protection, and what is its activation threshold?

The MAX603CPA achieves reverse-current protection by monitoring VIN and VOUT and switching the internal substrate bias to the more positive node. This turns off the P-channel pass transistor when VIN falls 6mV to 20mV below VOUT, limiting reverse leakage to ≤10μA - essential for maintaining backup supply integrity in dual-source systems.

Can the MAX603CPA be used in adjustable-output configurations, and how is the output voltage set?

Yes, the MAX603CPA supports adjustable output via its SET pin. Connect an external resistor divider (R1–R2) between OUT and GND, with SET tied to the R1–R2 junction. Output voltage follows VOUT = 1.20V × (1 + R1/R2), enabling precise 1.25V–11V regulation. For fixed 5V operation, simply tie SET to GND.

What is the shutdown behavior of the MAX603CPA, and how quickly does it exit shutdown?

Driving the OFF pin low disables the MAX603CPA, reducing total supply current to ≤2μA. When OFF transitions high, the device exits shutdown in ≤200μs (measured from 0% to 95% of final VOUT), with ≤1% overshoot. OFF threshold is VIN-dependent - e.g., >3.0V required at VIN = 6V - so avoid deriving OFF drive from fixed 3.3V logic rails.