Analog-to-Digital (ADC) converters have been an essential building block of electronic design for years. As ADC components get faster, new data interfaces are required in order to keep up with the faster data rates while providing very high data integrity. The objective of this project was to design an inter-IC ADC interface for converters with data bandwidths as high as 56 Gigabytes per second. The main goal for this project was to create a mechanism for interfacing a general-purpose high-speed ADC integrated circuit with an FPGA. This will enable applications that can benefit from the reprogrammability offered by FPGAs as well as those that could not justify a monolithic integrated solution for cost reasons. The interface presented is based on the physical layer of the IEEE 10GBASE-KR specification for 10 Gigabit Ethernet (10GE). Leveraging this specification provides significant benefits as it defines most of the services required by the interface, such as effcient encoding and forward error correction. Furthermore, using an interface as widely used as 10GBASE-KR leverages significant validation work as well as widespread support in mainstream FPGAs and by IP providers. The report will provide an analysis of the requirements of the ADC interface and a description of the architecture proposed. One key aspect of the design of the system was the analysis of the e ects of random bit errors in the channel and how to deal with them while making a robust interface. The causes of error are described and the critical sections of the system were simulated to validate the choice of Forward Error Correction solution. Finally, the report describes the working prototype system built in an FPGA board and provides a description of the performance achieved. / text

As wireless communication is ever-evolving, demanding higher data speeds, the requirementsincrease for the ADC, and the requirements for the comparator, which is one of the mainbuilding blocks, increase as well. The primary purpose of the comparator is to compare twovoltage levels and provide a logic output. One significant advantage of dynamic comparatorsis that they are more power-efficient than traditional comparators. There exist many differentarchitectures for dynamic comparators. In this thesis, the most promising designs areoptimized and evaluated over various parameters, such as speed, noise, offset, and hysteresis,while minimizing power consumption. The thesis includes a traditional StrongARM-latch,a double tail, and four triple tail comparators. The StrongARM-latch was the most powerefficientdesign while all the parameters were within the requirements, which was unexpected.

La chaîne de réception des téléphones mobiles de dernière génération utilisent au moins deux étages de transposition en fréquence avant d'effectuer la démodulation en quadrature. La transposition en fréquence augmente la complexité du système et engendre de nombreux problèmes tels que la limitation de l'échelle dynamique et l'introduction de bruit issu de l'oscillateur local. Il est alors nécessaire d'envisager une numérisation du signal le plus près possible de l'antenne. Cette dernière permet la conversion directe d'un signal analogique en un signal numérique à des fréquences intermédiaires. Elle simplifie ainsi la conception globale du système et limite les problèmes liés aux mélangeurs. Pour cela, des architectures moins conventionnelles doivent être développées, comme la conversion analogique-numérique utilisant la modulation Sigma-Delta à temps continu. La modélisation comportementale de ce convertisseur analogique-numérique, ainsi que la conception des principaux blocs ont donc été l'objet de cette thèse. L'application d'une méthodologie de conception avancée, permettant la simulation mixte des blocs fonctionnels à différents niveaux d'abstraction, a permis de valider aussi bien la conception des circuits que le système global de conversion. En utilisant une architecture à multiples boucles de retour avec un quantificateur multi-bit, le convertisseur Sigma-Delta passe bande à temps continu atteint un rapport signal sur bruit (SNR) d'environ 76 dB dans une large bande de 20MHz. / Wireless front-end receivers of last generation mobile devices operate at least two frequency translations before I/Q demodulation. Frequency translation increases the system complexity, introducing several problems associated with the mixers (dynamic range limitation, noise injection from the local oscillator, etc.). Herein, the position of the analog-to-digital interface in the receiver chain can play an important role. Moving the analog-to-digital converter (ADC) as near as possible to the antenna, permits to simplify the overall system design and to alleviate requirements associated with analog functions (filters, mixers). These currently requirements have led to a great effort in designing improved architectures as Continuous-Time Delta-Sigma ADCs. The behavioural modeling this converter, although the circuit design of the main blocks has been the subject of this thesis. The use of an advanced design methodology, allowing the mixed simulation at different levels of abstraction, allows to validate both the circuit design and the overall system conversion. Using a multi-feedback architecture associated with a multi-bit quantizer, the continuous-time Bandpass Delta-Sigma converter achieves a SNR of about 76 dB in a wide band of 20MHz.

The motivation behind this work is to target the demand for high-speed medium-resolution ADCs for satellite communication systems. An 8-bit, 12.5GS/s folding-interpolating ADC was designed in 0.25µm, 190GHz SiGe BiCMOS technology from IHP. The ADC consists of a THA, a reference resistor ladder, folding amplifiers, an interpolating resistor string, a comparator array, a digital encoder, a coarse quantizer and a bit synchronizer. Post-layout simulation results of the ADC verify that its performance meets all the required specifications. By comparison to other high-speed ADCs, implemented in SiGe technologies, the present design features the highest sampling rate for 8-bit resolution ADCs to date with a good FOM (12.9pJ/conversion). The THA and the comparator were implemented experimentally and characterized to verify their performance and to ascertain the possibility of implementing the complete ADC. The experimental results meet the expected specifications and indicate that both circuits are suitable for the implementation of the ADC.

The motivation behind this work is to target the demand for high-speed medium-resolution ADCs for satellite communication systems. An 8-bit, 12.5GS/s folding-interpolating ADC was designed in 0.25µm, 190GHz SiGe BiCMOS technology from IHP. The ADC consists of a THA, a reference resistor ladder, folding amplifiers, an interpolating resistor string, a comparator array, a digital encoder, a coarse quantizer and a bit synchronizer. Post-layout simulation results of the ADC verify that its performance meets all the required specifications. By comparison to other high-speed ADCs, implemented in SiGe technologies, the present design features the highest sampling rate for 8-bit resolution ADCs to date with a good FOM (12.9pJ/conversion). The THA and the comparator were implemented experimentally and characterized to verify their performance and to ascertain the possibility of implementing the complete ADC. The experimental results meet the expected specifications and indicate that both circuits are suitable for the implementation of the ADC.