Selecting gate driver for smps

[johnsorious]

I'm trying to design and build a smps that has a 120VAC input with a 5VDC (2 Amp) output and this is what I have designed for it so far. I was thinking of having a pic18f4685 to do the pwm to drive the gate of my mosfet. According to my simulation results I need 18V ~42% Duty Cycle at 400KHz in order to have the buck converter work correctly. I'm having trouble picking out a gate driver that works with my design. Can anyone recommend a through hole ic that I can use on a breadboard to test out? Is there any ic's that do feedback also so that I can possibly eliminate using a pic chip? I can't buy a complete buck converter ic for my project and it has to be custom. Just trying to build the easier smps possible without buying an ic that does everything! I appreciate all the input. If you have some schematic of a simple buck converter laying around that isn't just an ic please share it.

The transformer is a 120V:12V in the design.

[Cavarval]

Hello,

There are several MOSFET Drivers in Multisim, but none is through hole. I know very little about circuit design, but did a quick search and I am wondering whether you can create the PWM with an LM555 (there's a lot of content in the web about how to do that) or similar and take its output through an amp to provide enough juice for the power MOSFET.