Difference in Ripple Suppression and Voltage Regulation?

[turkey3_scratch]

What is the difference in ripple suppression and voltage regulation? I understand that voltage regulation is how close a power supply's outputted voltage is to the ideal voltage on the rail. But what is ripple suppression? Are they interchangeable?

 

[jimmysmitty]

Most PSUs have both Ripple Suppression and Voltage Regulation.

Ripple Suppression is used to keep the slight variances in the direct current output from the PSU while voltage regulation is used to keep the lines feed with a more continuous voltage instead of a non-continuous voltage such as possible voltage drops due to loads on the rails.

They are not quite interchangeable

 

[makkem]

Hi
As you say voltage regulation is controlling the voltage to a particular value and the closer it gets to that value the better the voltage regulation.
PSUs have an AC voltage on the input and output a DC voltage,no conversion of AC to DC is exact with the result that there is a small AC voltage superimposed on the DC voltage and because of the way this shows up on an oscilloscope is called ripple.
So obviously the lower the ripple voltage the better is the AC to DC conversion.

 

[turkey3_scratch]

Okay, I think those descriptions kind of make sense. But if voltage regulation is bad, would not that cause ripples as seen in the oscilloscope?

 

[jimmysmitty]

Yes if a voltage regulator is not doing its job properly it can cause excess ripple. I proper voltage regulator will not create additional ripple but it wont remove any ripple either. They work on different parts of the voltage.

Ideally you want both to be perfect but that is near impossible due to the nature of electricity. So the lower the ripple and the tighter the regulation the better.

 

[turkey3_scratch]

If a component, say a graphics card, gets a current with 12.05 volts, what happens to excess volts so to speak? Like, how can it operate at 12.02 volts and also at 12.05 volts? And why do things turn bad after about 12.12 volts?

 

[jimmysmitty]

There is a lot more going on between the PSU and the GPU. The motherboard has its own regulators as does the GPU. They only pull the voltage they need from the 12V rail. This area is much easier to regulate than a PSU.

For the most part the excess voltage is wasted as heat.

You want better regulation because too much extra voltage will push beyond what the components can handle. If you have a part that is certified for 12V you can normally push 10% more but beyond that and the component starts to heat up more and possibly burn out components.

 

[makkem]

If the voltage regulation was bad you would get swings of too large a value as the load changed ,this would not cause ripples which are regular (think a sine wave) but spikes.
As the voltage regulator works on the DC voltage it would not really affect the ripples unless extremely large and hence the need for a separate ripple suppressor.