Ripple Measurements

In the following table you will find the ripple levels that we measured on the main rails of ZM850-HP. According to ATX specification the limits are 120 mV (+12V) and 50 mV (5V & 3.3V).


Ripple/noise suppression is very good for +12V and 3.3V rails and good enough for 5V.

Ripple at Full Load

In the following oscilloscope screenshots you can see the AC ripple and noise that the main rails registered (+12V, 5V, 3.3V). The bigger the fluctuations on the oscilloscope's screen the bigger the ripple/noise. We set 0.01 V/Div (each vertical division/box equals to 0.01V) as standard but sometimes we are forced to use 0.02 V/Div, meaning that the fluctuations will look smaller but actually this wont be the case.

Ripple at Crossload 2

As above the order of images is +12V, 5V and 3.3V.