YAN9VUSBC
Intro: YAN9VUSBC
(Yet Another 9 Volt USB Charger)
STEP 1: Parts and Testing.
PARTS:
5v regulator (Lm7805)
Female USB port
Resistor
LED
Braided wire (20g)
Used 9v battery (Walgreen's brand)
5 minute liquid epoxy
Non-conductive epoxy putty
The circuit design is from http://ipod.hackaday.com/entry/1234000270029372/ All I did was add an LED so I could see if the battery was good. He's got nice diagrams of the USB and regulator to help you wire this together.
5v regulator (Lm7805)
Female USB port
Resistor
LED
Braided wire (20g)
Used 9v battery (Walgreen's brand)
5 minute liquid epoxy
Non-conductive epoxy putty
The circuit design is from http://ipod.hackaday.com/entry/1234000270029372/ All I did was add an LED so I could see if the battery was good. He's got nice diagrams of the USB and regulator to help you wire this together.
STEP 2: Disassemble the Battery:
Pry the metal lip back from the bottom of the battery and straighten the edges as much as possible with pliers. Carefully pull out the plastic base and save. After that the innards should slip out without much trouble. Cut the negative lead going down the side and save the connector. Save the case.
I chose to use a Walgreens brand battery because it has nice thick plastic on the top and bottom. Duracell uses paper.
I chose to use a Walgreens brand battery because it has nice thick plastic on the top and bottom. Duracell uses paper.
STEP 3: Solder the Circuit Together:
For the USB I just drilled three holes in a row and cut out the rest of the rectangle with an Xacto knife. The USB should be mounted in the plastic before you solder the connections.
So the USB, LED, and resistor are on top and the regulator is on the bottom. The wire lengths are just to have enough room to epoxy the top in before the bottom, 2"-3".
So the USB, LED, and resistor are on top and the regulator is on the bottom. The wire lengths are just to have enough room to epoxy the top in before the bottom, 2"-3".
STEP 4: Prepare the 9v Case:
Sand the paint off the case with 400 grit sandpaper and rubbing alcohol. Carefully epoxy the LED and USB to the plastic base. Just use enough to tack it in place, don't get it in the USB.
Cut the case at about the 2/3 mark.
Score the inside of the case with a file or an awl to give the epoxy some kind of mechanical hold.
Cut the case at about the 2/3 mark.
Score the inside of the case with a file or an awl to give the epoxy some kind of mechanical hold.
STEP 5: Epoxy Putty the Top:
Put just enough epoxy putty to cover the components on top. Don't put it all the way to the edge, you want it to fit in the case.
Once the epoxy putty has cured (not fully, just enough that it doesn't deform when you push on it), put the top half into the case and seat it against the lip. While holding it against the lip drip a small amount of liquid epoxy around the edge to hold it in place.
After the top is held in place fill the remainder of the case with putty, leaving just enough room for the bottom to be pushed in. Push the wires into the case and force the top into the putty 1/16"-1/8" past the edge of the case.
Once the epoxy putty has cured (not fully, just enough that it doesn't deform when you push on it), put the top half into the case and seat it against the lip. While holding it against the lip drip a small amount of liquid epoxy around the edge to hold it in place.
After the top is held in place fill the remainder of the case with putty, leaving just enough room for the bottom to be pushed in. Push the wires into the case and force the top into the putty 1/16"-1/8" past the edge of the case.
STEP 6: Close the Case:
While the epoxy starts to harden, cut 1/8" slots at each corner to help them fold over. When the epoxy has pretty much set up bend each edge over to close the case. Burnish or sand any sharp edges.
STEP 7: Finished:
Test with a multimeter before plugging in your USB powered device.
373 Comments
Schmidty16 7 years ago
LightningJimmy 8 years ago
Please change the title! This was an awesome tutorial but, it took me forever to find it because the title was confusing. Had it not been me searching on google images for it, I would not have found this.
holymoses 8 years ago
Nice idea for the housing of it, but I always wonder how much capacity a simple 9v batterie shall have. I would rather put the transformer on a batterieholder containing AA or bigger primary cells.
PankajaGamage 9 years ago
Pranjal Joshi 12 years ago
can resistors decrease the voltage?
please rply someone
sweston 9 years ago
Cekpi7 12 years ago
Pranjal Joshi 12 years ago
but aftr charging my cellphone shows "bad contact of charger".. so wat can i do to repair dat??
Cekpi7 12 years ago
Pranjal Joshi 12 years ago
der is no fault..
n i nt yet got a multimeter to test output voltage.. :(
did u mean for 1st few mins. the voltage is more than 5v bt den it decreases below the minimum charging capacity of battery hence it shows bad charger contact????
if yes then wats the solution on it..
Roshy10 11 years ago
kumaran512 11 years ago
iApple guy 12 years ago
freakyqwerty 13 years ago
Cheeseduck 11 years ago
fogman103 13 years ago
freakyqwerty 13 years ago
mm3814 12 years ago
Dalton63841 12 years ago
http://focus.ti.com/lit/ds/symlink/ptr08100w.pdf
The switching regulator is still extremely small, and would easily fit if you left the casing only slightly longer. Also, switching regulators don't burn off the excess voltage, but instead use pulse. By turning the flow of current on and off VERY quickly, it simulates lower voltages. A linear reg gives you about 55% efficiency, whereas the switching reg gives you close to 90%, which means that battery will last longer also. Not to mention the added safety because that switching reg is rated up to 10 amps.
ledguy315 11 years ago