Patent ID: 7706158

Claim:
An amplifier with a switchmode power supply comprising: an amplification means; a power supply for said amplification means; the power supply utilizing a current fed topology; the current fed topology comprising: a source of rectified direct current voltage; at least one inductor with one end connected to the voltage source; at least one main switch connected in series with the inductor and voltage source; an isolation transformer having a primary and at least one secondary winding; said transformer primary being connected to the junction of said main switch and inductor, whereby the main switch closing allows current to increase through the inductor and voltage source, the main switch opening diverting the inductor current into the transformer, allowing the inductor to supply energy to the secondary winding; at least one rectifier and energy storage capacitor connected to a transformer secondary, as the current is limited by the inductor, no inductors are used between the rectifier and energy storage capacitor; said power supply utilizing an active clamp snubber; said active clamp snubber comprising: an auxiliary switch in parallel with a diode; a clamp capacitor; the auxiliary switch and diode anode being connected to the junction of the primary winding and the main switch; the clamp capacitor being connected to the auxiliary switch and diode cathode, the other end of the capacitor being connected to the source of rectified direct current voltage; the main switch being turned on a short time after the auxiliary switch is turned off; the main switch being turned off a short time before the auxiliary switch is turned on, such that the main switch and auxiliary switch are turned on when there is little voltage across them; the power supply utilizing a control means; and the control means operating and connected in such a way as to maintain a constant voltage across the energy storage capacitor, and to force the input current to be proportional to the input voltage.