I am using a tiny13, fastPWM 9,6mhz 50% duty cycle that is the highest current I can generate through a yellow led.

100uh inductor

2n7000 mosfet

BAT85 shottky diode

.22uf capacitor

I can drive one Yellow led at 10.05mA measuring the LED at that current I get 1.87V Battery measures 1.4V while circuit is running.

I have aome 1000uh and higher inductors but I get less power using the 1000 at any frequency I have tried so far.

1,4V goes into inductor -> thru mosfet, diode from that junction to capacitor cap to ground, I get 73V open circuit.

If I add a second inductor and fet I can get double the output and drive a white LED at 13.5mA.

How do I use a bigger inductor with just one mosfet to get up to 20mA? I have tried using two 100uh in series and parallel through the same mosfet but series I get the same and parallel I get 1/2 the power.