I have been searching the web & still cannot find what I want to make a buck or step-down converter using the N-MOSFET.
I have plenty of those from many dead ATX power supply.
I have looked at the ATMEL application note on the battery charger & they use the P-MOSFET.
My aim is the output will be 12V at 2A (ripple around 100mV pp) with an input of 21V <-> 26V DC.
However here the tricky part, I want to use the N-MOSFET as the switcher.
Normally you would use P-MOSFET type.
The components I will use, are an AVR chip, N-MOSFET, fast switching diode, inductor and capacitors.
Frequency 20KHz to 200KHz.(Not that fussy)
Is this possible ?
I know there many companies that have their own switcher ICs.
But, I would prefer to use or roll my own using any avr chip (ATtinyx or ATMegaX) in PWM mode to control the N-MOSFET.
Any suggestion or link will be greatly appreciated.
My aim is the output will be 15V at 2A (ripple around 100mV pp) with an input of 21V <-> 26V DC.