Portable USB Charger (Version 2.0)

Step 2 The Circuit Board (Simple way)

The following picture shows the prepared PCB before putting in the necessary components.

What your looking at is the underside of a PCB with the copper foil facing you.
The gray line represent the location where the cut is to be made. Make sure that the 3 sections are electrically isolated (do not conduct to each other).  If you have a dremel tool, you can score the copper cladding with a cutting wheel.

The black dots are the locations where holes are to be drilled.

Comments

[lewis94]

is there any video tutorials of this project because i got a rough idea but i think it will be easier to understand if i could watch it get made. thanks lewis94

[pillow-pants]

hi, I need some help with my own design for portable charger(check the attaches image): It's a real charging monster, it's supposed to charge from a 9v nokia cellphone charger or a 9V battery or a USB cable. It's supposed to act as a charger for normal USB type devices and mini B USB device types. to sum up: possible sources: 9V battery, 9v cellphone charger, USB cord (which i named USB out). possible loads: USB female connector (which i called USB in), male USB mini B. I know better than to use more than one source or load at a time. It wouldn't be smart to do so, right? Switch1 makes it possible to choose between the 9V battery and 9V charger without waisting the battery's power. Switch2 is there to protect the USB connectors in case I want to charge with the USB cable. my questions are thus: I noticed you used capacitors in your design. Why do you use them? where should I place them in my design? can you tell me if all of my switches are necessary? did i make any mistakes in my design?

[GoodAtIt]

The comment by Tysonscott2002 is correct about the capacitors, it is wise to put a capacitor in parallel to your design after the switch, even though the voltage from the cellphone charger is stable, there are still chances where you could create a surge while plugging cellphone charger in, possibly damaging the regulator. Another problem i noticed is that when you use the USB-in as a power source, there is a possible loop from the ground of the regulator to the v-out. I recommend put another switch in between the USB-in and the other USB out, just to be safe.

[tysonscott2002]

the reason he puts the capacitors in his design, is to prevent "oscillations", similar to a power surge, that the 5v regulator can put out, that way, your item thats being charged, is protected, ive made one like this as well, and i simply put a 1k resistor in between +5v and ground, right on the usb port, works fine

[lesclaypool397]

where does the resistor go? im guessing that you have the .1 uF capacitor run straight to it, and then have the resistor run to the USB port, but im not sure.

[bbmak]

Are there anywhere i can get the PCB for free?

[papertiger]

where is the resistor?