Gain and Bandwidth Boosting of Transimpedance Amplifier

In many useful systems, accuracy is desired. The accuracy is directly related to the amplifier open loop gain. Thus, it is necessary to have higher gain for better accuracy and performance of the amplifier. In transimpedance amplifier, many techniques have been employed to increase its gain. Conventional techniques used flipped voltage follower to increase the gain of the amplifier. In this work, a transimpedance amplifier using flipped voltage follower, a DTMOS technique has been used to increase gain. The basic idea behind the proposed work is to enhance the transconductance of the MOSFET transistor with the help of biasing technique via gate and bulk terminals. Since the ampifiers open loop gain is directly proportional to the transconductance of the MOSFET, the gain increases by increase in the transconductance. The bandwidth is also proportional to the increased transconductance, thus the bandwidth also increases.An additional improved bandwidth is also obtained. A gain of 16.84dB and a bandwidth as high as 8.09GHz is obtained by using DTMOS technique. It can be concluded that the proposed technique is very effective in increasing the gain and bandwidth of the transimpedance amplifier.