A fully differential third-order VHF G(m)-C filter based on linear transformation techniques
A fully differential third-order very high frequency (VHF) Gm-C filter based on linear transformation ( LT) techniques is presented in this paper. The systematic design method and the procedure are developed to realize LT Gm-C fillters efficiently. A third-order Butterworth lowpass filter embedded bandgap and bias circuits with 200 MHz cutoff frequency is implemented in the TSMC 0.18 mu m 1P6M process. The total harmonic distortion (THD) of the proposed filter is -43 dB with input signal 0.5V(p-p) and output loading capacitance 1 pF at 200 MHz. Power dissipation is 9.77 mW under 1.8 V supply voltage. Its core area occupies 0.188 x 0.186 mm(2). Post simulation and experimental results that confirm the theoretical analysis are obtained. Furthermore, the proposed circuits can be extended to high-order Chebychev and elliptic filters.
fully differential g(m)-c filter linear transformation.