Comparison of Two Layout Options for 110-GHz CMOS LC Cross-Coupled Oscillators

Abstract

Two 110-GHz oscillators have been developed in 65-nm CMOS technology. To study the effect of layout on the circuit performance, both oscillators had the same LC cross-coupled topology but different layout schemes of the circuit. The oscillator with the conventional cross-coupled design (OSC1), showed an output power of −3.9 dBm at 111 GHz with a phase noise of −75 dBc/Hz at 1-MHz offset. On the other hand, OSC2, with a modified cross-coupled line layout, generated an output power of −2.0 dBm at 117 GHz with a phase noise of −77 dBc/Hz at 1-MHz offset. The result indicates that the optimized layout can improve key oscillator performances such as oscillation frequency and output power.

Keywords

• Layout
• LC Cross-Coupled
• Oscillators
• Signal Generation
• 65-nm CMOS