LAUSR

Blind zone of a phase frequency detector (PFD) enhances the phase noise in a Charge Pump PLL. This paper presents a novel technique to reduce the blind zone which reduces the reference spur as well. In this proposed work a variable delay element is incorporated in the Reset path of the PFD. The overall PFD delay is maintained at a small positive value to avoid blind zone at lower phase noise. The performance analysis carried out in Cadence design environment and compared with the performance of a PFD using a fixed delay element in its reset path. The comparison shows that the phase noise is improved by 6 dB.