I'm experiencing some high-pitched squealing noise from my boost converter, I'm getting some resonating frequency when I start increasing the load current.The inductor is a 47uH inductor. The part number for the diode is MBRD640CTT4G.
This is my schematic:
I checked the power line with the scope and this is the 12V line @ 100mA using AC Coupling:
As you can see, the ripple noise isn't so bad, I'm getting about 200mV peak to peak.
But when I run it at 500mA load this is what happens:
The ripple is horrible, I'm getting about 4V p-to-p.
Any ideas what is going on?