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

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 44; no. 2; pp. 335 - 343
• Main Authors: Ferre-Pikal, E.S., Walls, F.L., Nelson, C.W.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-03-1997; Institute of Electrical and Electronics Engineers
• Subjects: Amplitude modulation; Applied sciences; Capacitance; Circuit noise; Electronics; Exact sciences and technology; Fluctuations; Guidelines; Low-noise amplifiers; Noise level; Phase modulation; Phase noise; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Transconductance; Transistors; Experimental result; Phase modulation; Low noise amplifier; Linear amplification; Theoretical study; Amplitude modulation; 1/f noise; Bipolar transistor
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/58.585118

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.