Experimenting with Magnetic Components - Boost Converter part 2: Build

RE: Experimenting with Magnetic Components - Boost Converter part 2: Build

Jan Cumps — Wed, 06 Oct 2021 16:37:18 GMT

I'm preparing to measure current through the inductor.

I have an island on the clad board that can be used for that.

I can pivot one pin of either the inductor or the diode to that island. Then put a current meter between that island and the original mount point.

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Here is the setup to measure the current through the inductor:

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And this is the adapted schematic:

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Best to have the current meter always connected. An inductor with the current path removed can behave funny.

RE: Experimenting with Magnetic Components - Boost Converter part 2: Build

Jan Cumps — Tue, 05 Oct 2021 18:41:02 GMT

spectrum:

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The middle = 75 kHz (almost switching frequency), 100 kHz / div, 10dBV

RE: Experimenting with Magnetic Components - Boost Converter part 2: Build

Jan Cumps — Mon, 04 Oct 2021 19:54:19 GMT

Preview of the noise on the boost converter working at 12 V input, 35.4 V output.

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The goal of this design is not to remove the noise, it's to build a device that doesn't overspend the noise budget.

Just out of curiousity, the efficiency at this point:

Pout = Vout² / Rl = 0.46 W

Pin = Vin * Iin = 12.00 * 0.05 = 0.60 W

Efficiency = Pout/Pin = 76.77%

RE: Experimenting with Magnetic Components - Boost Converter part 2: Build

genebren — Mon, 04 Oct 2021 15:59:01 GMT

Great blog. Clean, simple and to the point. There is a lot to be said about getting a lot done without spending a lot of money or using a lot of expensive equipment. I think focusing on the tech and less on the toys is a great way to encourage others to join in a learn the basics.