5 Amplifier Families: Basic Characteristics

Innovative circuit design and simplified tuning requirements from Analog Devices Inc. allow RF designers to quickly design solutions across the signal chain that fit the need for smaller, lower power consuming systems

By Ashraf Elghamrawi

The amplifier is one of the most versatile building blocks used in RF/IF signal chains today. They are commonly used throughout designs to overcome signal losses incurred from passive devices or elements. Throughout a transceiver RF amplifiers are required to increase signal strength. In the receiver these devices amplify faint incoming signals, and in the transmitter they increase signal strength as it approaches the final power amplifier stages. Since these losses occur across the RF/IF signal chain, Analog Devices has developed five families of amplifiers tailored to the needs of each particular radio section. The five varieties are the LNA (low-noise amplifier), IFA (intermediate-frequency amplifiers), driver amplifiers, gain blocks, and the VGA (variable gain amplifier).