A 0.1-1.5 GHz 8-bit inverter-based digital-to-phase converter using harmonic rejection

In this paper, a 0.1-1.5 GHz 8-bit inverter-based digital-to-phase converter (DPC) is proposed. Conventional inverter-based DPC suffers from poor linearity and limited output frequency range. To mitigate the linearity problem and extend the output frequency range, we propose to use harmonic rejection (HR) filter to cancel out the 3^rd- and 5^th-order harmonics of the phase interpolated signal. The residual INL and DNL can be further eliminated by nonlinear interpolation technique. Designed and fabricated in 65-nm CMOS technology, the DPC demonstrates a maximum INL and DNL of 2.18 and 0.89 LSB while consumes a power of 4.3 mW and occupies 0.06 mm² area.