<p>This paper summarizes the known power and electromagnetic (EM) side-channel attacks and defense for ADCs and compares them to hardware cryptographic engines (Cryptos). Through this comparison, we revealed several interesting gaps that could serve as a roadmap for future research, namely multiplicative masking, circuit-level hiding, security benchmarks, and beyond-SAR ADC security. We further proposed full-scale dithering and folding ADC as possible future directions. </p>