Dual Band Current Reusing VCO with Loop Filter and Sigma-Delta Modulators for PLL Applications

The promoted low power dissipation voltage-controlled oscillator (VCO) with low-pass filter of fifth order curer and low pass sigma-delta (ΣΔ) modulator are fabricated with tsmc 0.18 µm CMOS processing for phase-locked loop (PLL) controlled applications. The proposed dual-band current reusing VCO is used divided-by-2 to adopt low power dissipation, power saving and enhance performance. The proposed switching capacitors of dual-band ΣΔ modulator and filter optimized core chip area is report for PLL controlled applications.