I was thinking of making my own dc/dc converter for my laptop. The original Lenovo charger can give 20 V at 4.5 A. I I have a few questions: right now I wanna build a 12 volt to 20 volt converter. I have been looking at boost and buck converters but I don't know what toroid to use or how many windings or what electrolytic capacitor to use. I have a lot of electrolytes form disposable cameras, maybe I could use them. I also found this on ebay. would it work? https://www.ebay.com/itm/150W-DC-DC-Boost-Step-Up-Converter-12V-32V-to-15V-35V-24V-6A-Laptop-Power-Supply/262983318200?hash=item3d3b06fab8:g:fg4AAOSwIaFZFtCT

I have been looking at Powering laptop from 12V sources without inverter

the cuicuit in this post looks to complicated for me.

I rather wanna build my own using arduino or a 555 timer instead of buying a new , to learn , thanks. Hope it wasent to long

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    \$\begingroup\$ "the cuicuit in this post looks to complicated for me" There are ready made products for your application. \$\endgroup\$ – winny May 4 '18 at 10:24
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    \$\begingroup\$ Building a dc/dc converter is not an easy task. Try building smaller converters. 10w-20w etc. Also i doubt that converter is rated 150w. It has to be 15w or smth like that. \$\endgroup\$ – Hammers May 4 '18 at 11:28
  • \$\begingroup\$ Well, after you brush up on control theory and circuit theory we can talk. Building a DC to DC converter from the ground up could take a junior engineer a month or two. A better idea would be to use off the shelf components from linear or analog. Even then it will take a through reading of the datasheet and a week or two to select proper components, simulate the circuit, get the circuit built, and ensure that no component is exceeding current or power ratings. \$\endgroup\$ – Voltage Spike May 17 '18 at 18:11

I am a bit confused here. You are saying that you'd like to learn and at the same time posting a link to cheap ready-made DC-DC converter.

If you simply need to power your laptop then there are tons of suitable DC-DC available for under 10 bucks. Just make sure it accepts down to 9V input (the one you linked doesn't) if you planning to use it in a car.

If you do want to make your own then be warned - buying components would probably cost several times more.

Having said that, there are many DC-DC regulators that require just a few external components. For example LM2587/LM2588 from Texas Instruments. It's datasheet is full of useful examples that should be easy for you to replicate. Most important, the datasheet has the list of suitable standard transformers/inductors, which is the trickiest part to make yourself.

  • \$\begingroup\$ thanks I have ordered one now. I will hope its the right one :) \$\endgroup\$ – Martin Moltke Wozniak May 7 '18 at 13:03

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