Switching Currents Low-pass Filter Design

The aim of this paper is to design a switched-current low pass butterworth filter using the switched-current technology. The cut-off frequency is 3kHz, the attenuation more than 20dB when frequency is 7kHz,the sampling frequency is 20kHz.The switched-current technology is a new sampling technique of anolog signal. Current-model circuit is a new developing direction of integrated circuit. Euler approximation is a numerical value integral technique. The transform from variable S to variable Z can be completed by Euler approximation transform. Switched-current filter belongs to discrete-time filter. Since we have mature technology of the design of continuous-time filer, it's easy to find a transfer function in S field which based on the design requires. Then transform this function to a transfer function in Z field. Synthesis this transfer function in Z field using switched-current integraph.