I need some of your help to finish my project. I am an electronic and communication engineering.
We have a project in school. What comes up to my mind is to build a portable usb charger. Unfortunately it won't charge my phone, it only serves as a battery or a supply not a charger.
Can anyone help me what else to add in my project?

My materials are: 9 volt battery, 7805 regulator, switch, and usb female.

any suggestions would help a lot.
thank you!

 

The problem is the phone is not detecting the cable.
There are resistors wired to the data pins. For this the phone model is necessary.

 

The USB implimenter's forum (USBIF) has a standard that spells out in extreme detail how a USB phone charger is expected to work.
It is at the link below.
komposter.com.ua/documents/BC1.2_FINAL.pdf

 

I need some of your help to finish my project. I am an electronic and communication engineering.
We have a project in school. What comes up to my mind is to build a portable usb charger. Unfortunately it won't charge my phone, it only serves as a battery or a supply not a charger.
Can anyone help me what else to add in my project?

My materials are: 9 volt battery, 7805 regulator, switch, and usb female.

any suggestions would help a lot.
thank you!

If it is an Android phone, then I have no idea.
I assume it is an iPhone - specifically, a 5S or 6 with the little lightning cable. If so, there is a little controller chip in the cable end that goes into the phone.

See this article.
http://gizmodo.com/5945889/some-third-party-adapters-might-not-work-with-your-new-iphone