Design and Performance Analysis of Asynchronous GRO based Time to Digital Converter

An Asynchronous Gated Ring Oscillator based Time to Digital Converter (A-GRO-TDC) is proposed. Gating functionality is added to a simple Ring Oscillator which drastically improves the system performance with asynchronous operation. Energy saving is possible due to scrambling and first order noise shaping. The proposed 9 bit A-GRO-TDC is implemented in Cadence using 0.18μm digital CMOS Technology. Pre and post layout simulation with corner analysis shows good linearity. All these features with very little power between 16μW to 26μW make it suitable for IoT applications. It consumes an active area of 550μm x 410μm. .