13-11-2012, 05:39 PM
I used a 180Ω resistor as a load and found that the noise level was about 4mV irrespective of the voltage across, and therefore the current through, it.
Off-load was more interesting. The saw-tooth thing started at 10mV and increased with voltage until by the time this was at 15V it was 100mV. It then started to rapidly fall and by the time it was up to 18V the noise was down to 4mV.
I wouldn't swear to the accuracy of these figures as with the 'scope on 10mV/Div some of the 'noise' could be radiated stuff being picked up by the wires rather than coming direct from the PSU.
- Joe
Off-load was more interesting. The saw-tooth thing started at 10mV and increased with voltage until by the time this was at 15V it was 100mV. It then started to rapidly fall and by the time it was up to 18V the noise was down to 4mV.
I wouldn't swear to the accuracy of these figures as with the 'scope on 10mV/Div some of the 'noise' could be radiated stuff being picked up by the wires rather than coming direct from the PSU.
- Joe
