Guidelines for designing BJT amplifiers with low 1/f AM and PMnoise

摘要

In this paper we discuss guidelines for designing linear bipolarnjunction transistor amplifiers with low 1/f amplitude modulation (AM)nand phase modulation (PM) noise. These guidelines are derived from a newntheory that relates AM and PM noise to transconductance fluctuations,njunction capacitance fluctuations, and circuit architecture. We analyzenthe noise equations of each process for a common emitter (CE) amplifiernand use the results to suggest amplifier designs that minimize the 1/fnnoise while providing other required attributes such as high gain.nAlthough we use a CE amplifier as an example, the procedure applies tonother configurations as well. Experimental noise results for severalnamplifier configurations are presented