A Cryogenic 1 GSa/s, Soft-Core FPGA ADC for Quantum Computing Applications
H. Homulle (TU Delft - OLD QCD/Charbon Lab, TU Delft - QuTech Advanced Research Centre)
S.M.C. Visser (TU Delft - QuTech Advanced Research Centre, TU Delft - OLD QCD/Charbon Lab)
E Charbon-Iwasaki-Charbon (TU Delft - OLD QCD/Charbon Lab, TU Delft - QuTech Advanced Research Centre)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
We propose an analog-to-digital converter (ADC) architecture, implemented in an FPGA, that is fully reconfigurable and easy to calibrate. This approach allows to alter the design, according to the system requirements, with simple modifications in the firmware. Therefore it can be used in a wide range of operating conditions, including a harsh cryogenic environment. The proposed architecture employs time-to-digital converters (TDCs) and phase interpolation techniques to reach a sampling rate, higher than the clock frequency (maximum 400 MHz), up to 1.2 GSa/s. The resulting FPGA ADC can achieve a 6 bit resolution (ENOB) over a 0.9 to 1.6 V input range and an effective resolution bandwidth (ERBW) of 15 MHz. This implies that the ADC has an effective Nyquist rate of 30 MHz, with an oversampling ratio of $40\times $. The system non-linearities are less than 1 LSB. The main advantages of this architecture are its scalability and reconfigurability, enabling applications with changing demands on one single platform.