Converting a USB to 12V step up cable to provide a 9V output
https://www.olimex.com/Products/Breadboarding/BB-PWR-3608/resources/MT3608.pdf
http://www.resistorguide.com/resistor-smd-code/
https://www.olimex.com/Products/Breadboarding/BB-PWR-3608/resources/MT3608.pdf
http://www.resistorguide.com/resistor-smd-code/
I wonder if it's really necessary to use the powerbank boost. Using a USB-A socket and a lithium cell with only a protection circuit, it would bypass the boost circuit and go directly from 3.7V to whatever is needed, eliminating one efficiency loss. This would also avoid the powerbank cutting out during high current draw to meet the power requirement of the device.. If more input current is needed, just use a larger cell or multiple cells in parallel.
Interesting to look inside the usb connector! These are normaly centre positive? If I want one of these cables with centre negative, can I just reverse the cables on the usb connector? Thanks in advance.
I see USB powerbanks that can output 5V, 9V or 12V (out of the USB connector) but there is no voltage selector in them. How the output voltage is selected in this case? Is there any communication between device (let's say a phone or tablet) and powerbank to select USB out voltage? Or does it output always 12V and the device limit the voltage to 9V or 5V? Or how? 🤔 Many USB power banks with USB connectors only (no extra DC outputs) and no selector are specified "USB (5V, 9V, 12V)". Or this can only reffer specifically to USC-C outputs?
Excellent, thank you!
I've never come across that SMD labelling system yet. That's hell annoying !
That huge resistor is pretty dodgy Julian ! lol
You couldn't scavenge an SMD off a dead TV or old router ?
Seriously though, thanks for sharing this as I've ordered a box of these to play with !
Do these create a noise if used with audio gear? Thinking of paying a parabolic mic kit I have bought from 5v u
Is there a possiblity to change the usb input terminal to a power jack female input? There are four pins of the usb in the board, which is postive and negative on that from lwft to right?
Cool leads!! And nice fix, we'll done!
I guess I was doing my math wrong I was dividing 2,320 by 44,200 to get 0.0524 x 12 was 0.629v Thank You!
with the amount of money you spend with that person. i hope you at least go your money back for the 2 incorrect ones
Did someone ask u to post this…..oooleeee
How make concert 12v to 3v
Thanks to this video I was able to convert from 12V to 9V a similar cable equipped with a chip labeled AL229. I found nothing about this chip on the web. I did a bit of reversed engineering to draw the schematics. Then measured the reference voltage with a DVM (0.6V). Using the same formula I calculated the value of the modified resistor divider (378K/27K). Instead of adding a resistor in parallel, I removed the SMD resistor and soldered a 390K resistor insulated with a bit of heat shrink tubing. Works great! Thanks Julian!
I need a 9volt steped up to 12volt any idea what I need to buy
Where did you buy these from??
Hi, please is there any way to turn usb to 12v 6a?? anyone? thx
hi, I want to use a 12v fan to cool the underside of my laptop, can this cable be used from my computers usb in order to power a 12v fan effectively?