Methods, systems and apparatus for a controller for fast transient response, the controller including a linear compensation circuit for controlling output voltage during steady state operation and a non-linear control circuit to generate a non-linear signal during transient periods, only a first pulse of the non-linear signal is injected during each transient period. The combination linear and non-linear control provides stability and reduces delay times for fast transient response. The non-linear control circuit includes a step up and a step down non-linear control circuit for producing the non-linear signal with a short delay time when the load voltage is less or greater than the reference voltage. An embodiment includes an adaptive circuit or generating a current signal dependent on the load current, the current signal is combined with the output voltage to reduce the difference between the reference and output voltages.

A DC-to-DC converter having a transformer with a primary and a tapped secondary, two serial output filter inductors connected parallel with the secondary, a center output filter inductor connected between the secondary tap and serial output inductors, two serially connected switches connected in parallel with the two output inductors for receiving a signal to control operation of the switches during steady state and an output load connected between the serial connection of the serial output inductors and serial switching devices. The transformer primary side connected with double-ended primary-side topologies. The transformer secondary and output filers configured to form a current tripler rectifier, current quadtupler rectifier or current N-tuper rectifier. The output filter inductors evenly share output current resulting in reduction of current and thermal stress during high current application and the rectification topology has simple driving for synchronous rectifier application without increasing complexity of control and operation of primary-side topologies.

There is provided an isolated power converter. More particularly, in one embodiment, there is provided a power converter including a first magnetic core having a primary winding and a secondary winding around the first magnetic core. The power converter also includes a second magnetic core having a first leg, a second leg coupled to the first leg, and a third leg coupled to the first and second legs, wherein a part of the third leg is equidistant from the first leg and the second leg. The power converter also has a first winding encircling the first leg, a first end of the first winding coupled to the secondary winding, a second winding encircling the second leg, a first end of the second winding coupled to the secondary winding, and a third winding encircling the third leg, a first end of the third winding coupled to a second end of the first wining and to a second end of the second winding.