title: Guidelines for designing BJT amplifiers with low 1/f AM and PM noise.
abstract: In this paper we discuss guidelines for designing linear bipolar junction transistor amplifiers with low 1/f amplitude modulation (AM) and phase modulation (PM) noise. These guidelines are derived from a new theory that relates AM and PM noise to transconductance fluctuations, junction capacitance fluctuations, and circuit architecture. We analyze the noise equations of each process for a common emitter (CE) amplifier and use the results to suggest amplifier designs that minimize the 1/f noise while providing other required attributes such as high gain. Although we use a CE amplifier as an example, the procedure applies to other configurations as well. Experimental noise results for several amplifier configurations are presented.
authors.affiliation: Nat. Inst. of Stand. and Technol., Boulder, CO.
authors.forename: E S
authors.initials: ES
authors.lastname: Ferre-Pikal
authors.forename: F L
authors.initials: FL
authors.lastname: Walls
authors.forename: C W
authors.initials: CW
authors.lastname: Nelson