Multiplied ΔΣ Time to Digital ConverterのNoise shaping改善の検討

抄録

Previously, the method has been proposed to reduce the quantization noise of the fractional N-PLL and the spurious due to the reference leak by placing a DLL before the PLL. We have previously proposed Multiplied ΔΣTDC, which solves the phase noise problem and spurious due to DLL delay device manufacturing variation. However, in the previous proposal, there was a trade-off between spurious reduction and quantization noise improvement by ΔΣTDC. In this paper, we propose a Multiplied ΔΣTDC that solves this problem and always has the effect of Noise shaping by ΔΣTDC.