A 60 GHz CMOS combined mm-wave VCO/divider with 10-GHz tuning range

This paper proposes the use of N-push operation for combining the functions of the VCO and dividers in the mm-wave frequency range. If employed in a PLL, the combined VCO/divider (C-VCO/D) would potentially provide wider tuning range than traditional mm-wave PLLs employing injection locked frequency dividers, thus exploiting the full range available in the 60 GHz band (57 GHz-64 GHz). The C-VCO/D is fabricated in 130 nm IBM CMOS technology and achieves a tuning range from 55 GHz-65 GHz using a VDD =1.5 V, I_core = 20 mA, and I_buffer = 15 mA. The C-VCO/D has a phase noise of 97.1 dBc/Hz at 1 MHz Offset.