優れた帯域平坦特性を有する1GHz帯2段高利得増幅器の開発

摘要

2段高利得増幅器で優れた帯域平坦特性を実現するために、高利符と安定性を両立させる回路形式に　ついて検討した。今回は回路安定化のために、入出力ダンピング回路とトランジスタ負帰還回路を導入した。両者の効果による周波数特性への影響を調べ、解析結果を元にそれらを組み合わせて、実際に増幅回路を設計・試作した。その結果、比帯域20％において、基底利得40．9dB、利得偏差0．2dBを実現することができた。%To realize an excellent gain flatness for 2-stage high-gain amplifier, a circuit configuration, which can achieve both high-gain and stable performance, is studied. This time, an input/output damping circuit and a negative feedback circuit are introduced to stabilize the circuit. The effects on the frequency characteristics by the both circuits are investigated. Then, the amplifier is designed and fabricated based on the simulation results, where the both circuits are properly combined. As a result, the experimental amplifier are successfully demonstrated with an excellent performance, of which is fundamental gain of 40.9dB and in-band gain ripple of 0.2dB for 20% fractional bandwidth.