A compact and low-power digital-domain noise coupling technique is proposed for higher-order CT DSM implementation, exploiting the architectural advantage of a SAR ADC and a simple digital filter. With an 8b SAR ADC and a second-order digital noise coupling filter, a prototype fourth-order DSM achieves 74.4dB SNDR for 10MHz BW with an OSR of 16 in a 28nm CMOS, showing an FoM(S_DR) of 174.5dB.