lowering output ripple
I have designed a power supply capable of delivering 2A @ 5v with tny280 ,but the output ripple is about 400mv,no matter how I change the output self from 3.3uH to 150uH,the output ripple and spikes remains 400mv.
What should I do?
Comments
Increase output capcitance to lower output ripple
That does not help...!
I have increased the capacitance to 6600uf, but the spikes are in the same range!
I suspect the spikes you talking about are common mode induced into probe and are not actuall ripple. when you measure output ripple you take the ground clip off the probe and use a short connection to ground (barrel)of probe. The tip of probe should directly contact test point. Also the probe tip to barrel of should have a 1uF cremamic and 10uf electrolytic capacitor directly across it -- this is a common set-up to eleiminate common mode noise into probe pickup
Here I have attached the PI expert design file and pcb file.