Analog Devices Inc./Maxim Integrated MAX604EPA

Overview

MAX604EPA from Maxim Integrated is a low-dropout, low-quiescent-current linear regulator with fixed 3.3V output and adjustable mode capability (1.25V–11V), featuring a 500mA P-channel MOSFET pass transistor, 240mV dropout at 200mA/3.3V, 15μA typical quiescent current, and reverse-current protection - deployed in battery-powered portable instruments and solar-powered devices.

For engineers reviewing the MAX604EPA datasheet, MAX604EPA pinout, MAX604EPA application, or MAX604EPA equivalent, this page delivers verified electrical parameters, thermal behavior under load, Dual Mode™ feedback configuration, shutdown timing (200μs exit), and real-world stability guidance for 10μF COUT designs.

Technical Context

The MAX604EPA implements a 1.20V bandgap reference and error amplifier driving a P-channel MOSFET pass element, enabling dropout voltage proportional to rDS(ON) × IOUT rather than base-drive losses. Its dual-mode comparator selects internal feedback (SET ≤ 80mV → 3.3V) or external resistor divider (SET > 150mV → adjustable).

Reverse-current protection activates when VIN falls 6–20mV below VOUT, switching substrate bias to the more positive rail and limiting reverse leakage to ≤10μA. Thermal shutdown engages at TJ = +160°C with 10°C hysteresis, causing pulsed regulation during overload.

Key Specifications

Pinout & Package

MAX604EPA uses an 8-pin plastic DIP (dual in-line package) with through-hole mounting and 0.3-inch body width. GND pins (2,3,6,7) serve as thermal conduction paths; all must be soldered to copper for rated 727mW dissipation at TA = +70°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LT1761ES5-3.3#TRMPBF and TPS76333DBVR, the MAX604EPA provides 3.3× higher output current, 5.7× lower quiescent current, integrated reverse-current blocking, and Dual Mode™ flexibility - making it uniquely suited for industrial battery-backed systems demanding robustness and longevity.

Availability

MAX604EPA is available at Aetrix Electronics and suitable for portable instrumentation, solar-powered data loggers, and industrial handheld terminals requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX604EPA 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 MAX603/MAX604 family was engineered specifically for battery-powered systems needing ultra-low IQ, low dropout, and reverse-current isolation - targeting pagers, cellular handsets, and portable test equipment in the 1990s and early 2000s.

FAQ

What is the maximum continuous output current for MAX604EPA at 3.3V output?

The MAX604EPA delivers up to 300mA continuously at 3.3V output under standard conditions (TA = +25°C, VIN ≥ 4.3V). At higher ambient temperatures or elevated input-output differentials, derating applies per the 727mW power dissipation limit of its 8-pin DIP package - for example, at TA = +70°C, continuous current drops to ~220mA with VIN = 6V.

Does MAX604EPA support adjustable output voltage, and how is it configured?

Yes, MAX604EPA supports adjustable output from 1.25V to 11V using external resistors on the SET pin. Connect R1 between OUT and SET, and R2 between SET and GND. The output follows VOUT = 1.20V × (1 + R1/R2), with VSET tolerance of ±40mV. For stable operation, keep R2 ≤ 1.5MΩ and ensure SET impedance <10kΩ in fixed-mode to avoid spurious mode switching.

What is the purpose of the OFF pin on MAX604EPA, and what logic levels activate shutdown?

The OFF pin on MAX604EPA is an active-low enable input. Driving OFF ≤ 0.4V places the device in 2μA shutdown mode, disabling all internal circuitry. To enable regulation, OFF must exceed the voltage-dependent threshold: ≥2.0V at VIN = 4V, ≥3.0V at VIN = 6V, or ≥4.0V at VIN = 11.5V. Fast CMOS/TTL edges (<1μs rise/fall) are required to prevent indeterminate states.

How does reverse-current protection work in MAX604EPA, and what is its activation threshold?

MAX604EPA's reverse-current protection monitors VIN vs. VOUT and switches internal substrate bias to the more positive rail when VIN falls 6–20mV below VOUT. This turns off the P-channel pass transistor, limiting reverse leakage to ≤10μA. The feature enables safe use with backup batteries or redundant supplies without external diodes, preserving system efficiency and reliability.

Can MAX604EPA be used with ceramic output capacitors, and what is the minimum recommended value?

Yes, MAX604EPA is stable with ceramic output capacitors, but the minimum recommended value is 3.3μF - using smaller values risks oscillation across temperature and load. For optimal transient response and stability over the full -40°C to +85°C range, 10μF is specified. Input capacitance should be 0.1μF–10μF; larger values improve line-transient rejection but are not required for basic stability.