> Or is it reacting too quickly? Some power supplies need a minimum ESR > so that the output cap acts as an RC filter.
The LDO has its own bypass cap (0.1u) at its terminals. The 4.7u is after the transistor that enables the rail to the OLED. It buzzes with both PNP and P-MOS, and those should provide sufficient resistance to avoid ringing that way. Besides, as I've said before, the ringing's waveform corresponds to the data on the OLED, like a video signal. It's not a constant ripple like a power supply problem, and goes away when the oled is filled with all dark pixels. _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user