A novel digitally programmable quadrature oscillator using DCVDGA

In this paper a novel digitally programmable voltage mode (VM) quadrature oscillator (QO) employing DCVDGAs has been presented. The idea of DCVDGA is developed by inserting a digital control unit (DCU) with conventional VDGA The proposed oscillator configuration consists of two DCVDGAs along with three grounded passive components (two capacitors and one resistor) and offers following beneficial features: (i) all the grounded passive elements are used (ii) independent control of frequency of oscillation (FO) and condition of oscillation(CO) (iii) independent electronic control of FO (iv) independent digital control of FO and (v) low active and passive sensitivities. The parasitics effect of DCVDGA's at high frequency behavior and tunability of presented topology is also shown. The performance of proposed circuit is verified using SPICE simulation with TMSC 0.18μm process parameters.