Analog Devices Inc./Maxim Integrated MAX667EPA

Overview

MAX667EPA from Maxim Integrated is a low-dropout linear voltage regulator delivering up to 250mA output current with typical dropout of 150mV at 200mA, 20µA quiescent current in normal mode, and -40°C to +85°C operating range. It features Dual Mode™ operation (fixed +5V or adjustable 1.3V–16V output), integrated low-battery detector (LBO), shutdown control (SHDN), and dropout detector (DD), used in battery-powered instrumentation and portable radios.

For engineers reviewing the MAX667EPA datasheet, MAX667EPA pinout, MAX667EPA application, or MAX667EPA equivalent, key selection criteria include dropout voltage vs. load, quiescent current in shutdown (0.2µA typ), LBI/LBO threshold accuracy (±30mV), SET input bias (<10nA), and compatibility with 10µF output capacitor for stability across temperature.

Technical Context

The MAX667EPA uses a micropower bandgap reference (1.22V trimmed), PNP pass transistor, and dual-comparator architecture: one selects fixed/adjustable mode via SET pin logic (>50mV threshold), the other implements low-battery detection against the internal reference. Its error amplifier drives the pass device with feedback sourced either from internal resistors (for +5V) or external divider (for programmable output).

Dropout detection is implemented via DD - an open-collector PNP output that sources current when VIN–VOUT falls below ~300mV - enabling early warning of regulation loss. Shutdown disables OUT, LBO, and DD while reducing IQ to <1µA, with SHDN threshold defined at 1.5V (VIH) and 0.3V (VIL).

Key Specifications

Pinout & Package

MAX667EPA is supplied in an 8-pin plastic DIP package (0.300" wide), compatible with through-hole prototyping and legacy industrial PCBs. Pin assignments are electrically identical to SO-package variants but with larger pitch and thermal mass.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM2931Z-5.0 and TPS76350, the MAX667EPA uniquely integrates adjustable output, ultra-low shutdown current, and dual-purpose monitoring outputs (LBO + DD) in a rugged DIP package - making it optimal for space-constrained, battery-critical industrial instruments where feature density and long-term reliability matter.

Availability

MAX667EPA is available at Aetrix Electronics and suitable for battery-powered instruments, portable radio receivers, and solar-powered data loggers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX667EPA 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 semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX667EPA belongs to Maxim's micropower linear regulator product line, designed specifically for energy-constrained, battery-operated systems needing precision voltage regulation, intelligent power monitoring, and extended temperature operation.

FAQ

What is the minimum input voltage required for the MAX667EPA to maintain 5V output regulation?

The MAX667EPA requires VIN ≥ VOUT + dropout voltage. At 200mA load, typical dropout is 150mV, so minimum VIN is 5.15V. At lighter loads, dropout decreases - e.g., 100mV at 100mA yields 5.10V minimum. Absolute minimum specified input is +3.5V, but regulation is only guaranteed above dropout threshold.

Can the MAX667EPA be used with an adjustable output voltage below 5V?

Yes. The MAX667EPA supports output voltages from +1.3V to +16V using external resistors R1 and R2 on the SET pin. For example, setting VOUT = 3.3V requires R2/R1 ≈ 1.71 (with VSET = 1.22V). Input bias at SET is <10nA, allowing high-value resistors (e.g., 1MΩ) without accuracy loss.

How does the dropout detector (DD) output function in the MAX667EPA?

The DD pin is an open-collector PNP output that begins sourcing current when VIN–VOUT falls below ~300mV. It does not switch digitally but provides analog warning - current increases sharply near dropout. A 100kΩ pull-down resistor converts this to a voltage for ADC monitoring or comparator triggering before regulation fails.

What is the purpose of the LBI and LBO pins on the MAX667EPA?

LBI is a comparator input referenced to the internal 1.22V bandgap. When voltage at LBI drops below this threshold, LBO - an open-drain output - pulls low to signal low battery. External resistor dividers on LBI allow custom thresholds (e.g., 3.0V or 4.2V), enabling flexible battery health monitoring without extra components.

Is the MAX667EPA pin-compatible with earlier versions like the MAX666?

Yes - the MAX667EPA is explicitly described as a pin-compatible upgrade to the MAX666 for applications with VIN > +3.5V. It improves upon the MAX666 with higher output current (250mA vs. 150mA), lower dropout (150mV vs. 350mV), and enhanced thermal performance across the -40°C to +85°C range.