Analog Devices Inc./Maxim Integrated MAX667CSA

Overview

MAX667CSA from Maxim Integrated is a low-dropout, positive linear voltage regulator delivering up to 250mA output current with typical dropout of 150mV at 200mA load and 20µA quiescent current in normal operation. It features Dual Mode™ operation-fixed +5V output or adjustable output (1.3V–16V) via external resistors-and integrated low-battery detection (LBO), shutdown control (SHDN), and dropout detector (DD). It is used in battery-powered portable instruments requiring stable, micropower regulation.

For engineers reviewing the MAX667CSA datasheet, MAX667CSA pinout, MAX667CSA application, or MAX667CSA equivalent, key selection criteria include dropout voltage at 200mA, quiescent current in shutdown mode (0.2µA typ), LBI/LBO threshold accuracy (±30mV), SET input bias (<10nA), and SO-8 thermal derating (5.88mW/°C above +70°C).

Technical Context

The MAX667CSA uses a PNP pass transistor architecture with a trimmed 1.225V internal bandgap reference and dual-comparator supervision: one selects fixed/adjustable mode via the SET pin, the other implements low-battery detection by comparing LBI to the reference. Its error amplifier drives the pass device with feedback sourced either from internal resistors (SET = GND) or an external divider (SET > 50mV).

Dropout detection is implemented via the DD pin-an open-collector PNP output that begins sourcing 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

MAX667CSA is housed in an 8-pin SO (Small Outline) package, surface-mount compatible, with standard JEDEC MS-012AC footprint and 1.27mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LT1129CS8-5 and TPS76350DBVR, the MAX667CSA uniquely integrates programmable output, low-battery detection, and dropout warning in a single SO-8 package-reducing component count and board area in battery-critical systems where functional integration outweighs minor dropout or quiescent current trade-offs.

Availability

MAX667CSA is available at Aetrix Electronics and suitable for battery-powered portable instruments, pagers and radio control receivers, solar-powered environmental sensors, low-power wireless sensor nodes, and handheld test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX667CSA 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, automotive, and communications applications.

The MAX667CSA belongs to Maxim's micropower linear regulator product line, designed specifically for battery-operated portable electronics where ultra-low quiescent current, low dropout, and integrated power-supervision features are essential.

FAQ

What is the maximum output current specification for the MAX667CSA?

The MAX667CSA delivers up to 250mA of continuous output current, as confirmed in the Electrical Characteristics table under "Maximum Output Current" (IOUT = 250mA, TA = +25°C). This rating applies across the full input voltage range (+3.5V to +16.5V) and is thermally limited by the SO-8 package's 471mW dissipation ceiling at +70°C ambient.

How does the MAX667CSA implement low-battery detection?

The MAX667CSA implements low-battery detection using the LBI input and LBO output: LBI compares an external voltage (e.g., from a resistor divider across the battery) to an internal 1.225V reference; when LBI falls below this threshold, LBO-a CMOS open-drain output-sinks current to ground. The MAX667CSA datasheet specifies ±30mV tolerance on the LBI threshold and confirms LBO functionality across the full operating temperature range.

Can the MAX667CSA be configured for output voltages other than +5V?

Yes, the MAX667CSA supports adjustable output voltages from +1.3V to +16V using the SET pin and two external resistors (R1, R2). When SET is biased >50mV above ground, the internal feedback path switches to the SET node, and VOUT = 1.225V × (R1 + R2)/R1. The MAX667CSA datasheet provides design equations, tolerance guidance (±25mV on VSET), and examples for common output values.

What is the quiescent current of the MAX667CSA in shutdown mode?

The MAX667CSA draws 0.2µA typical quiescent current in shutdown mode, as specified in the Features list and Electrical Characteristics table under "Quiescent Current" (IQ = 0.2µA typ, shutdown mode). This value is measured with SHDN > 1.5V and is validated across the full 0°C to +70°C operating temperature range for the MAX667CSA variant.

Does the MAX667CSA require an external output capacitor, and what value is recommended?

Yes, the MAX667CSA requires an external output capacitor for stability. The datasheet specifies a minimum of 10µF aluminum electrolytic or tantalum capacitor, with ESR requirements varying by temperature (e.g., ≥1Ω at –40°C, ≥0.5Ω at +85°C). Figure 4 in the MAX667CSA datasheet provides the exact ESR vs. temperature curve, and Figures 4–5 detail alternative stabilization schemes using series resistors.