Abstract

This dissertation describes the design of a CMOS 900-MHz bandpass amplifier that is suitable for RF transceivers. The work employs the state-of-art inductive degeneration techniques to minimize the noise figure and explores the use of lossy spiral inductors in high frequency circuit to realize input matching networks on-chip. A Q-compensation circuit is included to achieve a 25-MHz 3-dB bandwidth. Besides, a center frequency tuning circuit is also embedded to compensate for frequency deviations due to process variations. In the first prototype, a second-order bandpass amplifier had been fabricated in standard 0.8 μm single-poly, triple-metal CMOS process (HP SCN26G) provided by MOSIS ®. With a 3-V supply, at 950-MHz and a 3-dB bandwidth of 25-MHz, the measured voltage gain is 26 dB and the input S 11 is-13 dB. Under the same baising condition, the input third-order intermodulation product (IIP 3) and input-referred 1-dB compression point (P o,1-dB) are- 21.5 dBm and-31.5 dBm respectively. The image rejection at 140-MHz away from the desired signal is 20 dB. In addition, the Q of the amplifier can be tuned from around 2 to infinity and the center frequency can also be varied from 930 MHz to 1040 MHz. On the grounds that the measured

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