In this paper, we propose a noise reduction method for a Vernier Time-to-Digital Converter (VTDC) using a first-order noise shaping structure and a gated ring oscillator (GRO). An 11bit VTDC with 4 p s effective resolution was designed and developed for a high performance All Digital Frequency Synthesizer (ADFS). The VTDC realized in 180nm CMOS, its power consumption depending on the time difference between input edges; 1 to 11mA from a 1.5 V supply.