before testing my system I like to know if there are problems, not to burn my Arduino or L293D
Arduino power comes from the battrie,
logic power to the L293D comes from arduino
Vs of the motors comes from the battrie and GND comes from the arduino,
is that normal?
please see the picture
The basic idea to obtain logic power for the L293D from the +5V output of the Arduino is fine.
However, a 9V PP3 battery is not sufficient to power most motors, and it is not a good idea to power a motor and an Arduino from the same power source -- voltage spikes from the motor can damage the Arduino or interfere with normal functioning.
thankyou brother for help
but i use two sources, one for the arduino and the other for L293d , which GND i have to connecte to L293d ?? the GND of the Vs(pin9) or the GND of the Vss(pin8) , the Vs is taked from arduino
All grounds should be connected together.
i use a laptop charger for motors and a battrie 9v for arduino, should i connect the charger to the battrie ???
You need to know how much voltage and current the motors require (in particular the stall current) in order to choose a suitable motor power supply. It would be helpful if you could provide a link to the motor specifications or datasheet, or the manufacturer's product page.