Increasing DAQ output current to fire optocoupler

[fazel7]

Hello
I want to pulse to PC853 with DAQ(Data Acquisition). But output current of DAQ is 400uA (0.4mA) that this current can not ability to fire optocoupler (PC853)! what is your opinion for solve this problem? Can i use transistor for increase current? Or use current bufer like ULN2803?
Thanks

 

[chuckey]

You do not say what your needed current is, but a single transistor will give you at least 50 X more or a darlington pair X 1000. Depends if you have any other uses for the spare sections of the ULN2803.
Frank

 

[fazel7]

Thanks for your attention dear Frank;
Required current to firing PC853 optocoupler is at least 10mA. Following your order i can get for example 300uA from DAQ and at least 15mA from single transistor collector. Right!?:smile: