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This paper presents an artificially intelligent Flash ADC with enhanced resolution from 4 to 10 bits. Unlike conventional approaches, this artificial intelligence (AI)‐based architecture avoids the use of many number of comparators in the Flash ADC when the ADC's resolution changes from 4 to 10 bits. This work initially gets the digital output of a 4‐bit existing Flash ADC as a training data set and then uses these 4‐bit output bits and sends to resolution enhancement logic (REL) block to vary its resolution without increasing the hardware complexities. After simulation, it is observed that the proposed ADC is of SNR of 24.13 dB for 4‐bit Flash ADC designed in SCL 180 nm CMOS technology and increases from 36.89 to 60.70 dB for 6 to 10‐bit resolution, respectively. The sampling frequency of the proposed architecture ranges from 3.6 to 1.04 GHz for a change in resolution from 4 to 10 bits. The FoM of 235 fJ/conv‐step in the training phase is obtained, and it varies from 56 to 20.3 fJ/conv‐step in the next phase of the testing and the prediction. The estimated area of the proposed 4‐to‐10‐bit variable resolution Flash ADC is 235.23×301.67 μm2. [ABSTRACT FROM AUTHOR]

A dual‐loop ADPLL architecture with 3‐bit flash TDC and background calibration‐based VCO is presented in this paper. The major aim of this work is to achieve the low jitter, low power, fast locking, and PVT‐insensitive ADPLL using simple flash TDC and gain calibrated VCO. A simple flash‐based 3‐bit TDC in the main loop is used which helps in achieving the fast locking with lower power consumption in ADPLL. The novel low phase noise VCO, with gain calibration in another loop, is used to fasten the locking process and jitter reduction due to any PVT variations. Therefore, both flash TDC and dual loop in the proposed ADPLL architecture help in achieving the fast locking. Proposed ADPLL is designed in SCL 180 nm CMOS technology at 1.8 V. The resolution of 3‐bit flash TDC is 3 ps. The achieved jitter of ADPLL is 1.83 ps with a phase noise of −153 dBc/Hz and locking time of 1.7 μs. Total power consumption is 5.3 mW at a frequency of 1.6 GHz. [ABSTRACT FROM AUTHOR]