MAX840ESA+T

Overview

The MAX840ESA+T is a low-noise, regulated switching voltage regulator designed to generate negative bias voltages for GaAsFET applications. It operates from an input supply of 2.5V to 10V and provides a single adjustable output ranging from -0.5V to -9.4V. Housed in an 8-SOIC package, this charge pump-based device delivers stable negative rail generation suitable for powering RF front-end components.

Feature Summary

• Generates regulated negative bias voltage specifically optimized for GaAsFET circuits
• Utilizes internal charge pump topology for efficient DC-DC conversion
• Supports wide input voltage range compatible with standard cellular power rails

Applications

• Cellular telephone transmitter biasing
• GaAsFET amplifier gate bias supply
• RF front-end module negative voltage generation

Procurement Notes

Verify the specific suffix 'T' indicates tape-and-reel packaging when sourcing. Confirm RoHS compliance status through official manufacturer documentation. Ensure the SOIC-8 footprint matches your PCB layout constraints. Check for obsolescence notices as Maxim Integrated products may have lifecycle changes.

Selection Notes

Select this component when a compact, low-noise negative voltage source is required for GaAsFET devices. The integrated charge pump eliminates external inductors, simplifying design compared to traditional flyback converters. Suitable for space-constrained mobile handsets where board area is limited.

Part Context

Part of the Maxim Integrated linear and switching regulator portfolio. Designed for portable communication equipment requiring precise negative bias control. Complements positive LDO regulators in dual-rail power systems for RF transceivers.

Replacement Considerations

Check for direct pin-compatible alternatives within the MAX84x family. Verify if newer generations offer improved efficiency or lower quiescent current. Cross-reference with other GaAsFET bias ICs if lead times are critical.