Analog Devices Inc./Maxim Integrated MAX604ESA+

Overview

The MAX604ESA+ 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 an internal 500mA P-channel MOSFET pass transistor, 240mV dropout at 200mA, and 15μA typical quiescent current - designed for battery-powered portable instruments and solar-powered devices.

For engineers reviewing the MAX604ESA+ datasheet, MAX604ESA+ pinout, MAX604ESA+ application, or MAX604ESA+ equivalent, key selection criteria include dropout voltage under load, reverse-current protection threshold (6–20mV), thermal shutdown behavior (160°C), Dual Mode™ feedback configuration, and SO-8 package thermal derating (1.8W at +70°C).

Technical Context

The MAX604ESA+ employs a 1.20V bandgap reference and error amplifier to regulate output via internal or external feedback; its Dual Mode™ comparator selects between preset (3.3V) and adjustable operation based on SET pin voltage (<80mV for internal divider). The P-channel MOSFET pass transistor eliminates base-drive current, enabling stable 15μA IQ across load and temperature.

Reverse-current protection activates when VIN falls 6–20mV below VOUT, switching substrate bias to limit reverse leakage to ≤10μA; foldback current limiting delivers 350mA short-circuit protection below 0.8V output and 1.2A above 0.8V with VIN–VOUT > 0.7V.

Key Specifications

Pinout & Package

MAX604ESA+ is housed in an 8-pin SOIC (SO-8) package rated for 1.8W dissipation at +70°C, with four GND pins serving as thermal conduction paths - requiring soldering to large copper planes for reliable 500mA operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS76333QDBVRQ1 and MCP1703T-3302E/MB, the MAX604ESA+ delivers higher output current (500mA vs. ≤300mA), lower dropout (240mV vs. ≥120mV at comparable loads), integrated reverse-current protection, and Dual Mode™ flexibility - making it uniquely suited for thermally demanding, battery-backed, or adjustable-voltage systems requiring SO-8 reliability.

Availability

MAX604ESA+ is available at Aetrix Electronics and suitable for battery-powered portable instruments, solar-powered remote sensors, backup power systems, and industrial handheld terminals requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX604ESA+ 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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, automotive, and communications markets.

The MAX603/MAX604 product line was engineered specifically for ultra-low-power, wide-input-voltage battery regulation - emphasizing dropout efficiency, reverse-current isolation, and thermal robustness in compact SO-8 packages.

FAQ

What is the guaranteed output voltage tolerance for MAX604ESA+?

The MAX604ESA+ guarantees a fixed 3.3V output with ±1.5% tolerance (3.15V to 3.45V) across load (20μA–300mA), input (4.3V–11.5V), and temperature (–40°C to +85°C). This specification is validated per the Electrical Characteristics table in the official datasheet, with typical performance tighter at ±0.5% under nominal conditions. The MAX604ESA+ does not require external trimming to meet this spec.

How does the MAX604ESA+ implement reverse-current protection?

The MAX604ESA+ uses internal substrate switching to detect when VIN falls 6–20mV below VOUT, then disconnects the pass transistor's body diode path and biases the substrate to the more positive of IN or OUT. This limits reverse leakage to ≤10μA - critical for backup battery integrity. Unlike diode-or schemes, this is fully integrated and requires no external components.

Can MAX604ESA+ operate in adjustable mode, and what is the minimum output voltage?

Yes, the MAX604ESA+ supports adjustable mode via the SET pin: connecting an external resistor divider between OUT and GND sets VOUT = 1.20V × (1 + R1/R2). The minimum output is 1.25V - determined by the 1.20V internal reference plus tolerance and noise margins. The SET pin's 150mV threshold ensures clean mode transition without oscillation.

What thermal derating applies to MAX604ESA+ in SO-8 package?

The MAX604ESA+ SO-8 package has a thermal derating factor of 23.6mW/°C above +70°C ambient, with 1.8W maximum continuous dissipation at +70°C. To sustain 500mA at high VIN–VOUT differentials, PCB layout must use all four GND pins connected to ≥1.3cm² copper area per Figure 4 in the datasheet - otherwise, junction temperature may exceed +150°C.

Does MAX604ESA+ require specific input/output capacitors for stability?

Yes: the MAX604ESA+ requires ≥0.1μF ceramic input capacitance and exactly 10μF output capacitance (tantalum or aluminum electrolytic) for guaranteed stability across –40°C to +85°C and 20μA–500mA load. Capacitors smaller than 3.3μF risk oscillation; larger output values improve transient response but do not affect loop stability. CIN and COUT must be placed within 5mm of respective pins.