The switched-capacitor SAR architecture has benefited tremendously from technology scaling. We first present a charge-injection-based SAR architecture that shrinks the die area needed for a SAR ADC and achieves outstanding energy efficiency. We go on to discuss pipeline ADCs using SAR sub-ADCs and a ring amplifier. We present a SAR- assisted pipeline that achieves record efficiency for >12-bit pipeline ADCs. We argue that SAR ADCs are among the most efficient stand-alone converters for advanced nodes and an important building block for other converters.