EEVblog 1607 - PSU Switching Noise Reduction via Vibration - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: March 31, 2024, 09:58:14 am
content: Physically vibrating your power supply at a sub harmonic of your PSU switching frequency can potentially lower your system noise. A practical demonstration.

author: isometrik
author_rank: Regular Contributor
timestamp: March 31, 2024, 02:49:58 pm
content: That effect is known as the fishbowl effect in the literature.

author: Xena E
author_rank: Frequent Contributor
timestamp: March 31, 2024, 05:31:57 pm
content: What a CockGave me a laugh though... keep it up!

author: tszaboo
author_rank: Super Contributor
timestamp: March 31, 2024, 06:03:04 pm
content: You have to be really careful to avoid the resonance cascade. Especially if you are working with the Anti-Mass Spectrometer.

author: .RC.
author_rank: Frequent Contributor
timestamp: April 01, 2024, 03:54:25 am
content: Easier to just go full Star Trek and change the polarity of the ODN junctions.

author: golden_labels
author_rank: Super Contributor
timestamp: April 01, 2024, 10:13:51 am
content: It’s a well known among IT experts method of reducing fan and disks vibration. Electrolyte in PSU’s smoothing capacitors crystalizes and the capacitor starts exhibiting a dip in conductance at specific frequencies. In general it’s not a problem and, where it is, manufacturers employspectrum spreading(you may recall this advertised on your old mobos). But it remains a problem in devices which rotate at fixed speeds, like computer fans and HDDs. Disks are particularly vulnerable, because their high inertia keeps the spinning frequency constant. Hitting the computer case in the right way produces enough of higher harmonics to make crystals in capacitors to break down, restoring unrestricted flow of energy.Dave is wrong on one thing: you can deliver MHz range vibrations. This is whatmedical ultrasonographyuses. The reason it doesn’t work for reducing spikes is the wavelength. Sound wave at 10 Mhz has wavelength of 1 mil, that is less than a thickness of US dollar bill. The wave passes through the capacitors and inductors as if they weren’t there, instead of being absorbed.

author: pdenisowski
author_rank: Super Contributor
timestamp: April 01, 2024, 02:36:45 pm
content: This was actually the subject of an IEEE paper

author: EEVblog
author_rank: Unknown
timestamp: April 01, 2024, 10:21:57 pm
content: Quote from: pdenisowski on April 01, 2024, 02:36:45 pmThat must be the one I read

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 01, 2024, 11:41:48 pm
content: Excellent!

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 01, 2024, 11:49:34 pm
content: Quote from: EEVblog on April 01, 2024, 10:21:57 pmWell, that's the whole concept of acoustic black holes.

author: EEVblog
author_rank: Unknown
timestamp: April 02, 2024, 12:03:45 am
content: Quote from: golden_labels on April 01, 2024, 10:13:51 amCorrect. At Thales we used to do MHz range phased array sonar, it just passes right through.

author: egonotto
author_rank: Super Contributor
timestamp: April 02, 2024, 08:16:00 am
content: Hello,it is fitting that the authors of the article are called First and April in Polish.Best regardsegonotto

author: Keri Szafir
author_rank: Contributor
timestamp: April 02, 2024, 09:48:43 am
content: ...from the Beaver University! Pet that beaver and try once again just to see if it was not a Fluke.I'm Polish and haven't even noticed, LOL.

author: Ranayna
author_rank: Super Contributor
timestamp: April 02, 2024, 12:31:41 pm
content: I have to admit: You got meI know that you always post these videos. Yesterday i actually thought that i might have missed it due to the Algorithm.Now i read this thread, and yet again i had to realize: Damn, you Australians are earlyI did not miss the video, it totally flew over my head.But while your earlier videos were obvious, this got me...

author: strawberry
author_rank: Super Contributor
timestamp: April 02, 2024, 05:42:49 pm
content: oscillators may run off