Abstract: System and method for detecting one or more currents. For example, a system for detecting one or more currents includes: one or more current sampling units coupled to one or more terminal transistors respectively and configured to sample one or more terminal currents that flow between a system terminal of a power management system and one or more port terminals through the one or more terminal transistors respectively; one or more operational amplifiers coupled to the one or more current sampling units respectively and configured to generate one or more detection currents respectively, the one or more detection currents representing one or more magnitudes of the one or more terminal currents respectively; and a signal combiner configured to receive the one or more detection currents, generate a combined detection voltage representing a sum of the one or more magnitudes of the one or more terminal currents.

Abstract: Handshake controller and handshake control method for one or more charging protocols. For example, a handshake controller for one or more charging protocols includes: a port detection unit connected to a plurality of USB ports and configured to generate a detection signal; a port selection unit configured to receive the detection signal and connected to the plurality of USB ports; an interface unit connected to the port selection unit; and a digital handshake unit connected to the interface unit; wherein the port detection unit is further configured to: determine whether a single USB port of the plurality of USB ports is connected to a load device.