An integrated circuit that measures time intervals with high precision and accuracy has a wide range of applications including data conversion, ranging, and 3-D imaging. The resolution with which time intervals are quantized by a ring oscillator or delay line is limited by the minimum delay of an inverter in the technology. We propose the use of cyclic-coupled ring oscillators (CCROs) as a time-domain quantizer to achieve a combination of subgate-delay time resolution together with a short conversion time, thereby enabling data conversion with high resolution as well as high bandwidth. The resolution-power tradeoff in coupled oscillators is studied. Simulation indicates up to a factor-of-13 subgate-delay time resolution with 13 coupled oscillators. A real-time quantizing time-to-digital converter with coupled oscillators is designed for a time-domain analog-to-digital converter. Powered by a factor-of-8 subgate-delay time resolution of 1.6 ps obtained with nine coupled oscillators, and a sample time of 4 ns for 11-bit conversion, the converter delivers a 9.9-bit ENOB over a signal bandwidth of 125 MHz and an SFDR of 88 dB. Results demonstrate that CCROs is an attractive candidate as a high-precision high-linearity time-domain quantizer for data converters.

中文翻译：

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使用循环耦合环形振荡器的Subgate-Delay时间分辨率数据转换

以高精度和高精度测量时间间隔的集成电路具有广泛的应用，包括数据转换，测距和3D成像。通过环形振荡器或延迟线量化时间间隔的分辨率受该技术中反相器的最小延迟限制。我们建议使用循环耦合环形振荡器（CCRO）作为时域量化器，以实现子门延迟时间分辨率与较短转换时间的结合，从而实现高分辨率和高带宽的数据转换。研究了耦合振荡器的分辨率-功率折衷。仿真表明，具有13个耦合振荡器的子栅延迟时间分辨率高达13倍。设计了带有耦合振荡器的实时量化时间数字转换器，用于时域模数转换器。该转换器由九个耦合振荡器获得的1.6 ps的8倍子栅极延迟时间分辨率和11比特转换的4 ns采样时间提供动力，在125 MHz的信号带宽上提供9.9位ENOB SFDR为88 dB。结果表明，CCRO作为数据转换器的高精度高线性度时域量化器是有吸引力的候选对象。