Sai,
Yes, with all the resources already provided by others and your focused dedication you can pass the HANA developer certification using self study and practice approach.
One are that I would recommend that you focus is on data replication scenarios for SAP ECC and SAP BW data. You will have few questions on that. You should be fine if you review the scenarios in the SAP documentation for SLT and data services ( BODS).
Hope this helps! Good luck!
Rama Shankar