Digitally Programmable Lossless Floating Inductor Realization using Current Differential Amplifier (CDA)

A digitally programmable lossless floating inductor realization circuit is proposed. The proposed block uses current differential amplifier as an active block and the programmability is achieved through array of capacitors each one is connected to a switch, according to the logic 1 or 0 applied to the switch gate; the array size change and the programmability is achieved. The presented circuit realizes a tunable floating inductor tuned from L=26.624 mu H to 38.088mH. To show the reliability of the proposed block, Programmable resonant circuit has been implemented using the proposed circuit from frequency 51 kHz to 86 kHz. Also, Programmable low pass filter have been realized using the digital programmable block from frequency 6MHz to 17MHz. The simulation results has been demonstrated and discussed using PSPICE simulation for 0.18 mu m CMOS technology provided by TSMC. The proposed circuit uses +/- 1.5 V dual supply voltages.