This presentation will talk about the impacts of the total common-mode capacitance in a typical isolated gate-drive channel. This common-mode capacitance is often much larger than expected, predominantly due to the parasitic capacitance of the isolated bias supply. This parasitic capacitance connects directly from the low-voltage control circuit to the high-voltage and high-frequency switch-node in every half-bridge leg in a power stage. This causes a significant flow of noise current from switching node to low-voltage domain, resulting in power loss, voltage spikes and ringing, and higher common-mode EMI. A survey of the common-mode capacitance performance of various common solutions is presented, along with a mx of lab measurement and simulation results. The benefits of low-capacitance per channels solutions are presented.