I have designed a powerbank with 5v 1A but when I connect with mobile its showing charging but its not getting charged latter I came to know that D+ and D- pins from usb should connected in some way to make mobile charge but Ihad tried a lot but dont have a idea to connect D+ and D- pins so help me to fix it

 

You need a circuit like this:

 

Hello,

The following pages might interest you:
http://www.epanorama.net/newepa/2010/08/18/apple-charger-secrets/
https://learn.adafruit.com/minty-boost/icharging
http://www.obddiag.net/usb-power.html

Bertus

 

Ya thank you so much these site are really helpful and another doubt i am getting 5V 1A with the help of ic7805 voltage regulator but if i want use ic7805 my battery should be minimum 7.5 v so this circuit is very harder for powerbank and with the 3v or 4v battery can I boost to 5.12v and what are the steps and kindly give me some references to it

 

Hello,

The following page shows a charger that uses 3 Volts as input using the LT1302:
https://learn.adafruit.com/minty-boost/change-log

Bertus

 

cant we develope boost converter using 555 timer

 

Hello,

The problem with a normal 555 is that it needs a supply between 4.5 and 18 Volts.
The CMOS version of the 555 will work from 1.5 Volts, as stated in the datasheet.
Also regulating the output voltage will be very difficult to implement.
Feedback is possible with the 555:
http://www.dos4ever.com/flyback/flyback.html
This is for much higher voltages, but can be adapted to your needs.

Bertus

 

Please can you list me ic used for boost converters

 

Hello,

Here is the search page from linear about boost regulators:
http://www.linear.com/parametric/Step-Up_(Boost)_Regulators
And here the page from texas instruments:
http://www.ti.com/lsds/ti/power-management/boost-converter-integrated-switch-products.page#

Bertus