A Novel Continuous TDC Measurement Technique
Résumé
This paper presents a novel technique implementing a continuous Time-to-Digital Converter (TDC) measurement circuit that has been used for designing an Event-Based ADC (EB-ADC) implementing a LCSS (Level Crossing Sample Scheme). In the case presented in this brief, the EB-ADC has been connected to a bundled-data asynchronous digital ASK demodulation algorithm module, and has been sent to fabrication using FDSOI 28nm STMicroelectronics technology. For the ASK demodulation implementation purpose, only two crossing levels have been defined. Then, the EB-ADC is composed only by two comparators, one for each level. These comparators were characterized though an electrical simulation and then modeled in SystemVerilog in order to be integrated in a fully digital simulation. Thus, the TDC, its internal elements and the demodulation module has been synthetized and placed and routed, for obtaining the final layout. A post-layout simulation has been executed to validate the whole design and hence the continuous TDC measurement between each consecutive input request events. The obtained demodulation performance of the system has been a BER = 3.33∙10-7 for a bitrate of 6.78 Mbps and SNR greater than 16 dB.
