VLSI Society of India, IEEE Circuits and Systems Society Bangalore Chapter, and ParagaTI (TI India Technical University) jointly arranged a one-day seminar entitled Low Frequency and High Frequency Noise in Bipolar transistors on August 23, 2007. The speaker was Dr. Jayasimha Prasad, Maxim Integrated Products (USA) and the venue was the auditorium of Texas Instruments, Bangalore, India. The seminar was attended by about 30 participants. Dr Prasad emphasized that LF noise is a very important concern in analog and mixed signal circuits. Low frequency noise also affects the high frequency performance of oscillators, VCOs and mixers by generating phase noise. Mr.Jayasimha Prasad in his talk reviewed popcorn noise, flicker noise, shot noise, thermal noise and their behavior. He also described the methods of measuring the noise in devices. HF noise affects the performance of communication systems and sets the lower limit on the minimum detectable signal. Noise figure NF is a better parameter to characterize noise at higher frequencies. At any given frequency and Ic, there are four noise parameters that are needed to characterize the high frequency noise: minimum noise figure, noise resistance, optimum source conductance and susceptance. In addition, the associated gain of the device is also very important parameter. He highlighted how NF varies with Ic and frequency, introduced the concept of noise temperature to help us in making noise figure measurement. Set up for noise figure measurements were detailed out, and typical measurement results from transistors were shown. Methods of minimizing noise figure were also discussed. The talk subsequently concluded on how to perform phase noise and jitter calculations from 1/f noise for practical system applications.

Jayasimha Prasad obtained his Ph.D in Electrical Engineering from Oregon State University, Corvallis. For the past twenty four years, he has been engaged in developing high-speed GaAs and SiGe HBT technology. He has been with Tektronix for 12 years developing GaAs-based HBT technology for high-speed oscilloscopes. He was a Tektronix Fellow and he was the first in the world to demonstrate a 60GHz InGaP HBT IC technology with 28ps gate delay. During the past 12 years, he has been with National Semiconductor, Micrel Semiconductor and Maxim Integrated Products where he has developed SiGe BiCMOS processes for wireless and fiber optic applications which have resulted in several products.
Prior to the HBT work, Prasad has developed E2PROM processes at National Semiconductor and contributed to VMOS processes at AMI Semiconductor. Prasad is an IEEE Fellow and a Distinguished Lecturer of IEEE Electron Devices Society. He is member of the IEEE technical committees on Compound Semiconductor Devices, Compact Modeling and Education. He is currently serving in the IEEE Technical Field Awards Committees. Prasad has been serving in the technical committees of BCTM and IEDM. Prasad was an Adjunct Professor at Oregon State University. Currently, he is an adjunct faculty at Santa Clara University.