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DC-to-DC Converter

DC-to-DC Converter
I built this DC-to-DC converter for my 48V electric bike because I wanted to be able to plug-in some common 12V accessories, e.g. my cell-phone charger, or a GPS unit.
 
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Step 1Schematic

Schematic
Here's the schematic. The cap values are somewhat flexible depending on how much ripple you can tolerate. Be sure to observe the correct polarity for the electrolytic caps. I do not have a list of Digikey part numbers because I found many of the parts I needed at a local electronics surplus store. But all these parts (or something close) are available from Digikey.
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16 comments
Apr 14, 2011. 7:02 PMcam1128 says:
How would you make a 90V to 50V converter (with low amp levels)?
Jan 20, 2010. 11:34 AMfrank_w12 says:
is there a way to go from 15 to 12
Dec 8, 2009. 10:29 PMfatboyslim says:
Is there a way of having in input of between 9-15 volts and achieving a ouput of 48-60volts?
Jul 23, 2009. 1:21 PMkentdream says:
LM2576HVT - 12 should do the job, however 2576HVT-12 only provide 3A output.

thz author SCD. I was also searching for a 48dc to 12dc for my electric bike.

maybe we can share more ideas about e-bike =)
Apr 26, 2009. 5:23 AMsilencekilla says:
can you give us a list of the electronics components please?
Apr 24, 2009. 9:28 AMkelseymh says:
Very nice idea! To make it easier to reproduce by others (not everyone is familiar with building circuits or wiring connectors), could you consider showing some additional steps or details?

  • Provide a list of the necessary components, and sources (e.g., RS part numbers) if possible.
  • How are the Molex (? hard to tell from the pix) connectors pinned out?
  • What does the back of the perf board look like?
  • Use image notes to call out each component (on both sides of the board)
  • How did you make the car-lighter dongle?
  • It looks like you had to drill a clearance hole in the case for one of the caps.
  • You're using nylon standoffs because the case won't close?
Apr 24, 2009. 11:59 AMNachoMahma says:
. kelseymh makes some excellent points on how to make your iBle better, but, if one assumes that the reader has just a little bit of experience, it gives all the info needed. As is, I'd rate it 2½-3; with his suggestions incorporated and a few more details on assembly (eg, how the components are connected), possibly a 4. More info on theory of operation and how to adapt for other uses will give it a slight boost. . If the unit will be used for anything close to the rated 3A, a heatsink would be a good idea. Probably not an issue for cell phones and GPSs (?½A max?).
Apr 24, 2009. 8:28 AMBobS says:
Not visible, no components list. This way it cannot be built. How about formulas to calculate different in and outputs; or make it variable/ adjustable? How about current?
Apr 24, 2009. 9:36 AMatombomb1945 says:
Agreed, I would love to find out how to build this and step it down for a 24v system (Military Vehicles)
Jul 6, 2009. 8:57 PMmykelpogi says:
can you pls give more specific details on materials like voltage on capacitor , what kind of diode is shottky,inductor.. plss plss. can i use LM2575 instead of LM27576 more details pls.. because i real like to try ur work many thanks

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