Switching power supplies are newer to the market and incorporate switching regulators to convert electrical power efficiently. Unlike a linear power supply, the pass transistor of a switching-mode supply continually switches between low-dissipation, full-on and full-off states, and spends very little time in the high dissipation transitions, which minimizes wasted energy. This higher power conversion efficiency is an important advantage of switching power supplies. Also, switching power supplies are usually substantially smaller and lighter than linear supplies due to the smaller transformer size and weight. On the other hand, due to the required electronics on the PCB, switching power supplies are more complicated and can cause electrical noise problems if not carefully suppressed.
