DC/DC converter for powering USB devices

garrence

Pedelecer
Jun 10, 2010
76
1
I'm curious about adding a DC/DC converter to power USB devices. Primarily I think this would be handy for powering my Android phone running a mapping app (probably Maverick) in a handlebar mount. It could also be handy for powering the USB charged lights we're seeing on the market now - they could be hardwired and have their internal batteries removed.

Dear electronics buffs on the forum - do you think this nice small DC/DC converter would do the job?

TRACOPOWER|TEN 15-4811WI|CONVERTER, DC/DC, 15W, 5.1V/3A | Farnell United Kingdom

Do you just wire it up as-is, or does it need extra capacitors etc?
 

Vikki

Esteemed Pedelecer
Jan 12, 2009
442
2
That part will do the trick. There are others but I see it delivers up to 3A. You will probably want that if you are going to run a few things off of it. The data sheet doesn't mention anything about external circuitry so you should be able to use it as is.

Make sure you wire it up properly and pay particular attention to the fact that the output supply is fully isolated from the input supply.

Vikki.
 
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onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
I'm not entirely sure why they've included a signal wire, the unit is intended for powering the receiver and servo's of r/c models so it may be controllable via the transmitter.
A phonecall to the vendor should answer your query and confirm its suitability for your purpose.

Tony.

I've emailed vendor and will get back to you once reply received.
 
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garrence

Pedelecer
Jun 10, 2010
76
1
A phonecall to the vendor should answer your query and confirm its suitability for your purpose.
yes that would be sensible. So of course I haven't done that and have just gone ahead ordered one.

I'm sure they just include an extra wire for the sake of it.

Will report back!
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
yes that would be sensible. So of course I haven't done that and have just gone ahead ordered one.

I'm sure they just include an extra wire for the sake of it.

Will report back!
Had a reply and signal wire serve's no purpose, other than time consuming to remove.
Hope all goes well with modification.

Tony.
 
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garrence

Pedelecer
Jun 10, 2010
76
1
Yayy it's working a treat! I now have a USB socket near the front of the frame and the phone says it's charging when I plug it in!

Thanks, Tony!
 

Vikki

Esteemed Pedelecer
Jan 12, 2009
442
2
Excellent :D

Well done.

Vikki.
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
Yayy it's working a treat! I now have a USB socket near the front of the frame and the phone says it's charging when I plug it in!

Thanks, Tony!
Your most welcome. Ordered a couple myself.
Out of interest, what input power are you using and where are you picking up the power. Tony.
 
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garrence

Pedelecer
Jun 10, 2010
76
1
36V. On the wire from the battery prong there was already junction branching off to the lights so I connected it there. I didn't add a switch so I guess there may be a few mA of loss when it's not in use.

I used a short USB extension cable, chopping off the plug. Helpfully it had red and black wires, though of course confirm they are the power wires by using a multimeter.

The wire is just long enough to run alongside the rear brake cable to put the socket under the frame at the front, where the charge cable for whatever device can be plugged in. It also has plastic cap to keep out water when not in use.

Gary
 

flecc

Member
Oct 25, 2006
53,485
30,801
I used a short USB extension cable, chopping off the plug. Helpfully it had red and black wires, though of course confirm they are the power wires by using a multimeter.
[FONT=Arial, sans-serif]If no meter handy, view the mouth of the socket where you plug in, with the four metal contacts above the plastic centre support, the contacts are numbered 1 to 4 from left to right. [/FONT]


[FONT=Arial, sans-serif]Contact 1 = 5v [/FONT]


[FONT=Arial, sans-serif]Contact 2 = USB signal - [/FONT]


[FONT=Arial, sans-serif]Contact 3 = USB signal + [/FONT]


[FONT=Arial, sans-serif]Contact 4 = Ground (Negative)
[/FONT]
[FONT=Arial, sans-serif].
[/FONT]
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
36V. On the wire from the battery prong there was already junction branching off to the lights so I connected it there. I didn't add a switch so I guess there may be a few mA of loss when it's not in use.

I used a short USB extension cable, chopping off the plug. Helpfully it had red and black wires, though of course confirm they are the power wires by using a multimeter.

The wire is just long enough to run alongside the rear brake cable to put the socket under the frame at the front, where the charge cable for whatever device can be plugged in. It also has plastic cap to keep out water when not in use.

Gary
Just as a precaution best not have it connected while charging the battery and a switch to isolate it if need be, is always a good idea.
 

garrence

Pedelecer
Jun 10, 2010
76
1
Just as a precaution best not have it connected while charging the battery and a switch to isolate it if need be, is always a good idea.
Yep, there's a key switch on the battery itself so power doesn't get into the bike when it's turned off and charging. Ta for checking though.

I suppose that a twenty mile extension cable could be fun and remove the need for a battery entirely!
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
Yep, there's a key switch on the battery itself so power doesn't get into the bike when it's turned off and charging. Ta for checking though.

I suppose that a twenty mile extension cable could be fun and remove the need for a battery entirely!
I'm still waiting for someone to develop wireless technology for power supplies?
Maybe one day all roads will have embedded power rails and all vehicles will have some form of wiper to pick up power similar to bumper cars at the fair.
 

flecc

Member
Oct 25, 2006
53,485
30,801
I'm still waiting for someone to develop wireless technology for power supplies?
Maybe one day all roads will have embedded power rails and all vehicles will have some form of wiper to pick up power similar to bumper cars at the fair.
Upside down trolley buses:))), but a more sensible future than over a billion vehicles using batteries. I can't see how the latter could ever happen.
.
 

garrence

Pedelecer
Jun 10, 2010
76
1
- - - or could the roads grid take over some of the function of the national grid?
Just install maglev. Then we can do away with tyres, pothole repairs and gritting. Or vacuum tubes that you ride in! They've already got vacuum waste systems across whole cities.

Induction charging will be a big thing over the next few years for consumer electronics. dell already have a laptop with an induction charger and I've seen a video where the charger is on the floor and the laptop on the desk.

Induction charger will add to weight a bit because you'll need a coil on the bike.