i wish i could control bldc with arduino&L293DD.

L293DD DATASHEET:http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00000059.pdf

but i can't find the circuit....

many people control dc with L293DD.. not the BLDC...

 

This is because a BLDC motor is in effect a three phase motor. It take three phases of bipolar ( + and - voltage) DC square wave to drive it.

 

Have you reviewed this BLDC Motor Basics? You can get some idea's from it ...