EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: Konsolkongen on June 09, 2022, 03:26:54 pm
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Hi EEVblog forum.
I was watching these videos of a guy who wanted to reduce a buzzing noise from the PS5 power supply:
https://www.youtube.com/watch?v=tR3iyW68QuA (https://www.youtube.com/watch?v=tR3iyW68QuA)
https://www.youtube.com/watch?v=2Kl7EshQPdM (https://www.youtube.com/watch?v=2Kl7EshQPdM)
He claims that the noise is coming from the film capacitors on the power supply, and in his video that does appear to be the case. I would have assumed that the noise came from the coils or transformer, but looking at a datasheet for a film capacitor it does look like their insides are spun like a coil, so I figured that maybe there is something to this and I wanted to give it a try.
I ordered some replacement 1uF capacitors from Mouser that have the same AC voltage rating:
https://www.mouser.dk/ProductDetail/80-F861BZ105M310C (https://www.mouser.dk/ProductDetail/80-F861BZ105M310C)
I also added a bit of this electronic grade silicone to some of the components as he did in his video, in the hope that it would lessen any vibration causing noise:
https://www.mouser.dk/ProductDetail/910-EGS10W-20G (https://www.mouser.dk/ProductDetail/910-EGS10W-20G)
Unfortunately I don't hear much improvement after doing this. It may be a little bit better. I did recordings before and after, but the variation could just be slight difference in microphone placement.
The noise varies based on what's being drawn on screen. I think that the more power the console uses the more it buzzes, but I don't have a power meter to check this for sure. It never buzzes much at all when playing PS4 games (PS5 games are generally more demanding), and in the main menu it's whisper quiet.
Is it possible that the film capacitors is causing the buzzing? Or is it more likely to be other components on the PSU, or maybe even the mainboard?
iFixit pictures of the power supply and mainboard here (power supply located opposite of the crescent fan cutout):
https://guide-images.cdn.ifixit.com/igi/Qx2tDqSSJ6DC5inI.huge (https://guide-images.cdn.ifixit.com/igi/Qx2tDqSSJ6DC5inI.huge)
https://guide-images.cdn.ifixit.com/igi/V1oe41WkL35ZjyXh.huge (https://guide-images.cdn.ifixit.com/igi/V1oe41WkL35ZjyXh.huge)
https://guide-images.cdn.ifixit.com/igi/THJcQqFWZZG3UqWZ.huge (https://guide-images.cdn.ifixit.com/igi/THJcQqFWZZG3UqWZ.huge)
I hope I have provided a sufficient explanation.
Any advice would be appreciated. Thank you :)
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Yes, film capacitors can buzz. Under changing electric field film dialectric changes shape a little, it is stressed. If voltage waveform across it contains audible spectrum, this vibration can be heard. Very low frequencies, like for example 50Hz, will likely not be heard because of inefficient coupling between capacitor body, PCB and air. But higher frequencies could be loud enough to notice.
It looks you bought X class capacitor as a replacement. That's good, it is important to use the right type of capacitor.
Higher voltage rating capacitor could vibrate less, because of thicker dialectric, thats true. But it will be bigger. And again, make sure that it is X class.
Ultimatelly, you also want to reduce coupling to the PCB, so mounting capacitor softly and using short pieces of flexible wire for connection could help reduce audible noise. Until of course you will stop hearing the capacitor and start hearing transformer... Or vice versa. Switching supplies often make some noise, thats just how they are. Including the DC to DC converters on the motherboard.
In the end, I'm not sure why you would mess with a perfectly working power supply because of some slight buzzing.
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Yes, film capacitors can buzz. Under changing electric field film dialectric changes shape a little, it is stressed. If voltage waveform across it contains audible spectrum, this vibration can be heard. Very low frequencies, like for example 50Hz, will likely not be heard because of inefficient coupling between capacitor body, PCB and air. But higher frequencies could be loud enough to notice.
Hi Manul. Thank you for confirming this :)
It looks you bought X class capacitor as a replacement. That's good, it is important to use the right type of capacitor.
I did buy a few different kinds of film capacitors that would physically fit, but the ones linked were the only ones that have the same AC voltage rating as the original ones. (I couldn't tell from the video). The other ones I bought are 250V, and they are not X class either so they wouldn't be a good fit. I did read something along the lines of X class having selfhealing properties and should be used for mains power. Should have done some more research before ordering, but maybe I can find a use for the other caps another time :)
Ultimatelly, you also want to reduce coupling to the PCB, so mounting capacitor softly and using short pieces of flexible wire for connection could help reduce audible noise. Until of course you will stop hearing the capacitor and start hearing transformer... Or vice versa. Switching supplies often make some noise, thats just how they are. Including the DC to DC converters on the motherboard.
This is good advice. I actually did the exact opposite, and made sure that the caps were as flush against the PCB as possible, as I thought that would be the best way to minimise the buzzing.
As for using wires and mounting the caps softly, is this what you are suggesting?
(https://i.imgur.com/STnlspN.png)
Where the gray stuff between the caps and PCB is a silicone.
In the end, I'm not sure why you would mess with a perfectly working power supply because of some slight buzzing.
This is a fair point. I just find it annoying that my console does this where my friends apparently doesn't. As the amount of buzz depends on the amount of power being drawn, it will change on almost a frame by frame basis. If I look north I may hear nothing, but if I look west where there's a lot more geometry it may buzz. If the noise was constant I wouldn't be so bothered by it.
It's not that I can't drown out the noise with my surround system, but even then there are quiet moments in most games where I will hear it again ;D
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As for using wires and mounting the caps softly, is this what you are suggesting?
I don't know myself what exactly I suggest. First you would need to try how significant is sound coupling from capacitor to PCB. Maybe it is not worth the effort. It could be radiating most of sound directly from it's case to air. Anyway, I guess I would do a foam gasket at the bottom and soft wire extensions penetrating that foam. So capacitor would stand almost as it should, just slightly higher.
Silicone is not necessarily a good material to absorb vibrational energy. You need a material which dissipates vibrational energy into heat, otherwise it will not reduce the sound. Sound studios use foam. I'm really not an expert of making capacitors buzz less, I'm just speculating and making educated (hopefully) guesses.
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Thank you. It's much appreciated, and gives me some ideas on how to approach this moving forward.
I'll update this topic if I make significant improvements :)
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Just a thought on this. I'm working on a PS5 repair. Motherboard had a short across the 12V rail. And power supply was dead. I have fixed the power supply. The noise from the power supply is most likely due to the big inductor that is used as a resonant tank. It is an LLC switch mode power supply. The TEA2016AAT (replaces the DAP053T) has a fantastic application note ~200 pages long and it goes into detail about the audible noise generated by the resonant tank inductor. It is due to the burst mode that TEA2016AAT goes into. In burst mode, the IC goes from low-power mode and hold state. It is during the transitions between these bursts that create these audible sounds. Something to do with the interruption of the bursts (during holds) that changes magnetization current within the inductor leading to a mechanical force that is audible. The inductor core amplifies these sounds. Sound is most audible at the resonant frequency of the inductor. It can sound pretty bizarre. It is supposed to go away with increased load, but I was load testing mine after repair up to 200W and it just kept getting louder. Not sure if it is another issue that I haven't found.
I'll be posting a vid of the repair to my YouTube channel once the motherboard is repaired (if I can repair it lol).
-Frank