A81

Overview

The A81 is a discrete hybrid RF amplifier designed for broadband applications between 20 MHz and 250 MHz. It utilizes thin film manufacturing processes to ensure accurate performance and high reliability. The device features a two-stage silicon bipolar feedback design with an isolation transformer in the feedback loop, providing high reverse isolation exceeding 30 dB typical. Key electrical parameters include a typical gain of 26 dB, a noise figure of 2.6 dB, and a high-level output power of +17 dBm. The component is available in hermetically sealed TO-8 packages.

Feature Summary

• Discrete hybrid design utilizing thin film manufacturing processes for high reliability
• Two-stage silicon bipolar feedback architecture with integrated isolation transformer
• High reverse isolation capability exceeding 30 dB typical
• Hermetically sealed package options including TO-8

Applications

• GPS receiver front-end stages
• Broadband signal amplification in communication systems
• Cascadable amplifier configurations requiring high isolation

Procurement Notes

Verify the specific datasheet version and manufacturer documentation to confirm exact pinout and environmental screening requirements. Ensure the selected package variant matches the thermal and mechanical constraints of the target PCB layout. Cross-reference part numbers such as CA81 or A81-1 if alternative packaging or slight specification variations are required for the specific application design.

Selection Notes

Select this component when broadband operation from 20 MHz to 300 MHz is required with low noise characteristics. The high reverse isolation makes it suitable for cascaded stages where signal feedback must be minimized. Consider the TO-8 package for through-hole mounting or surface mount variants if space constraints dictate. Verify MIL-STD-883 screening availability if aerospace or defense grade reliability is mandated.

Part Context

MACOM Technology Solutions specializes in high-performance analog semiconductors for RF, microwave, and optical applications. The A81 belongs to their portfolio of discrete hybrid amplifiers, leveraging thin-film technology for precision. This product line supports industries including telecommunications, data centers, and industrial markets, addressing challenges in signal integrity and network capacity.

Replacement Considerations

Publicly confirmed substitute part numbers are not explicitly listed in the provided source material. Variants such as CA81 or A81-1 may exist within the same family but require direct datasheet comparison to verify functional equivalence regarding frequency range and package type.