Transistor switching using PIC18f4550

[DatsAbk]

Hello People...
I'm messed up with transistor switching using PIC18f4550.

I need to generate variable spikes by applying PWM signal at the base.

The collector voltage is set to be 12V and obviously base voltage will be 5V.Which transistor and which values of base resistor and collector resistor should i use?

These are the few available options with me:

2N2222
2N3904
BC547

 

[Tahmid]

You should mention the current requirement. How is the transistor connected?

Is it connected like this?

You can use base resistor and collector resistor 10k if all you need is the signal and you don't drive any load with it.

Hope this helps.
Tahmid.

 

[DatsAbk]

Yes Tahmid its connected like this.I need simple voltage spikes and current is henceforth not an issue.

 

[Tahmid]

So, 10k is fine. And you can use BC547. Exactly the way shown in the circuit in my post above.

 

[moustick]

Hi Tahmid,

I am facing the same problem and unfurtunaly the picture you posted is no more available. I am seeing only a black square with a X. Can you repost the diagram please?

Thank you
Mario

 

[Ahmmed Razu]

Try with the attached document. You should use 2N2219 if the PWM frequency is high or another high frequency transistor. this circuit will invert your input PWM signal if you need same PWM signal as input then you can use another similar circuit whose base will be connected to circuit 1 collector via 10k resistor and collector having 22K/1W resistor.