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[SOLVED] 5V to 12V with two transistors. Don´t work.

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aqua_life

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Hi,
I want to control a 12 Volt output with a microcontroller PIC18.
The output of PIC18 is 0V or 5V. I want to convert it to 0V or 12V.
I have searched a lot and the cheapest way to make it is with two transistor.
The 0/5 Volt output controls a NPN transistor and this one will control a PNP transistor.
I have tried it with real components and I have the same output for differents inputs.
With 0V in input I have 12V in output. I should have 0V. How can I make it?
I have tried with 8V instead of 12V and it works fine.
With 0V input I have 0V output. With 5V input I have 8V output.
Here you can see my schematic:
Thanks for your help

schematic.jpg
 

Add another 10k from the base of BC327 to +12V
 

I have tried a 10K resistor between Base and 12V. Same result. Always 12V.
I think I will read a book about transistors :)
Transistors are always a confusion.

- - - Updated - - -

Problem solved.
10K resistor between Base and 12V in BC327 (like you said) and 100K resistor in BC327 base instead of 10K.
Now perfect. Thanks for your help.
 

You may have a leaky BC 547. The PNP should switch off with the 10k as well.
 

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