I made a variable bench power supply using a Meanwell MSP200-24 switching power supply which outputs 24V at 8A, and connected to a variable buck booster unit which can output 0.5-30V and can do current limiting. However, it seems to generate a lot of noise on the signal, which makes it difficult to analyze and kind of amplication circuit. When i attach my oscilloscope to the output of the power supply at either stage, I get a sine wave that pulses from about 0.1V peak to peak down to 0.01V and the pattern repeats at a rate of 67kHz or so. The sine wave itself is at about 1 MHz. There is also a fainter since wave with a higher amplitude (about 0.4 V peak to peak). Even if the buck booster is switched off I still get the noise until the meanwell unit is switched off as well. Is this normal for a switching power supply? Should I be building a linear power supply?
Thanks for any help you can provide.
Here are a couple of images from the scope:
<a href=" removed link ” target=”_blank” rel=”noopener”>photo1
<a href=" removed link ” target=”_blank” rel=”noopener”>photo2
Here are a couple of images from the scope:
<a href=” removed link ” target=”_blank” rel=”noopener”>photo1
<a href=” removed link ” target=”_blank” rel=”noopener”>photo2
I have been having good luck with https://imgur.com/
Larry – N7LUF
@durham_ox Hopely someone can help you, as I do not know much about the power supply you are building.
A drawing of it would help to share to see what you are working on.
A switching power supply is noisy the way I know it and have not worked with one.
Larry – N7LUF
I would recommend a adjustable linear power supply switching mode power supplies are rf making machine’s the even back feed noise on the ac line
I would recommend a adjustable linear power supply switching mode power supplies are rf making machine’s the even back feed noise on the ac line
I totally agree with Tom, to use a linear power supply
Larry – N7LUF
Have you checked to see if you have any bad solder joints? Also, may move some of the wires or component leads around and see if your signal changes. It almost looks like you have an unintended mixer happening somewhere in your build. Maybe look for wires that are parallel to each other and may be causing induction between them?