Study and Analysis of A Simple Self Cascode Regulated Cascode Amplifier

Document Type : Original Article


Department of Electronics and Communication Engineering, Motilal Nehru National Institute of Technology Allahabad, India


This article proposed a simple self cascode RGC amplifier configuration to increase the gain and bandwidth. The cascode amplifier eliminates the miller capacitance between input and output and facilitates high gain, high input and output impedance with high bandwidth. However, the cascode amplifier requires relatively high supply voltage for proper operation and it decreases the output voltage swing by overdrive voltage. These issues are overcome by self cascode based RGC amplifier; even though it has low bandwidth due to the presence of one of its pole at low frequency. The bandwidth and output impedance of the conventional RGC has increased using a split length compensation technique. To improve the overall performance of the amplifier, introduced a simple self cascode RGC without using additional passive elements. The expression of gain and output impedance for the proposed amplifier is derived using small signal analysis. The calculated value of voltage gain for the projected circuit is 58.37 dB which is more than the self cascode based RGC. The power dissipation of the proposed circuit is 1.07 µWatt and it was compared with CS, cascode, self cascode and SC based cascode, RGC, SC based RGC amplifiers.


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