No one has claimed responsibility for the attack.
"The injured were able to go to the hospital themselves," an official said.
"Hopefully we will have more details on what exactly happened. For now the area where the bomb exploded has been closed to traffic in case there is a second bomb."
NTV, a private television station, said the bomb was placed in a rubbish bin outside the bank.
Percussion bombs produce a loud noise, disorientating people in the vicinity.
A double bomb attack had killed at least 17 people in a crowded area of Istanbul in July. The first blast was caused by a percussion bomb and the second, a more powerful explosion, ripped through the crowd.