The aim of this thesis is the analysis, the design and the implementation and the experimental validation of a new high current hot swap controller which allows designers to overcome the limitations of state-of-art systems related to linear mode operation of Trench power MOSFETs. A hot swap controller is a circuit that limits and manages the power flow during the start-up transient. This kind of circuitry is always present in rack electronic systems, especially in online servers and telecommunication equipment that provides services 24/7. In order to achieve a zero out of service time, maintenance and upgrade operations must be executed while the system is running.