一個以脈衝擴展法為基礎的時間至數位轉換器，改良傳統的雙斜率法的開關設計方式將誤差降低，並且搭配插補法來達到無限的量測範圍及高解析度。在不需要以鎖相迴路或延遲鎖定迴路來做連續校正的情況下，希望在不同的環境因素下，也能保有相同的解析度。本晶片的解析度為26.04ps，實現於TSMC 2P4M 0.35µm製程，晶片面積為0.31mm2，輸入參考頻率為80MHz，經量測驗證，其最佳解析度為25.95ps，最差解析度為26.14ps。

A 26.04ps high resolution CMOS time-to-digital converter (TDC) based on a pulse stretcher is proposed to own a theoretically unlimited input range. The reference clock frequency is designed to be 80MHz. In order to reach a higher effective resolution than that of conventional dual-slop TDC, a novel design is proposed to eliminate the error caused by switches. Without any continuous self-calibration, the stretching factor is expected to be fixed. The size of the TDC chip is 0.31 mm2 fabricated in the TSMC 0.35µm CMOS digital process. According to the measurement result, the resolution variation is as small as 25.95ps to 26.14ps.

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