Transistor Wiring Difference

[Xenobius]

Dear all,

I have a small question which I would like to confirm. What is the difference between both diagrams attached?

Thanks for your generosity
X

 

[shortbus=]

In the left side example the transistor is turned on to shut the power to the load OFF.

In the right hand example the transistor is turned on to turn the load ON.

 

[Xenobius]

Hey thanks for your reply. But I cannot understand how the left cct can actually shut off. How does it work?

Thanks

 

[ericgibbs]

Hey thanks for your reply. But I cannot understand how the left cct can actually shut off. How does it work?

Thanks

hi,
The junction of R2 and the Load is connected to 0V when the transistor is ON, so no current will flow in the load.

Its a very inefficient circuit

 

[Xenobius]

Ohh is now I understand better. Basically I once saw this configuration connected to a PNP in order to "Latch" the output.

Thanks
X