The large signal models of Si transistors

• Main Authors: Weng, Chung-chian, 溫崇謙
• Other Authors: Y.J.Chan
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/88595370164174171019

碩士 === 國立中央大學 === 電機工程學系 === 85 === The telecommunication channels are becoming jammed in recent years. It leads to the development in the aspect of high frequency circuits. In pursuit of high quality telecommunication products, the improvement of high frequency circuits is necessary, which makes transistor model of active component crucial in this situation. Considering the lower cost of silicon transistors, we extracted the component parameters from the circuit model of silicon transistor to increase the reliability in the circuit simulation. Our bipolar junction transistor was the Gummel Poon model. We measured the S-parameters for both the low frequency (20MHz-50MHz) and high frequency (40MHz-2GHz), and in this way we could calculate the internal component parameter instead of calculating it from the optimal simulation. In addition, we can have better initial values for other parameters. The DC part of the Gummel Poon parameter could be determined by measured Gummel Plots. The non-linear capacitor parameters could be calculated from the optimal simulation, and as a result the Gummel Poon model could be set. This model was then used in the design of high frequency circuit. For example, it could predict the frequency and phase noise of the VCO and improve its circuit characteristics. For MOSFET, we used the component with a TSMC gatelength of 0.6 um to measure its high frequency characteristics and resulted in an Ft value of 13.5 GHz, which was applicable in high frequency. Moreover, we also simulated its "small-signal" and "large-signal" models, and applied these in the high frequency circuits. We then used the results measured from this component to simulate the characteristics of LNA, and determined the phase noise to be 3.7dB, which implied that the development of this model would contribute to the application of MOSFET in the high frequency circuits.