transistor as a switch

[electronic_satya]

Hi all,

i was trying to solve one of the questions posted in this forum and while solving i got this doubt.
if a transistor is designed to work as a switch i can control the voltage and current of the output if the transistor is in ON mode i.e voltage is Vcc(supply voltage) and current is Vcc/RC (supply voltage/collector resistor). But i cannot control the current in the OFF mode and the voltage is fixed at 0V. Am i correct in my explanation? also will there be a situation where in OFF mode i need to supply some minimum current? how should i solve this kind of problem?

thanks and regards,
satya

---------- Post added at 14:26 ---------- Previous post was at 14:16 ----------

i think i got the answer. if anybody has any important point, please tell me.

thanks and regards,
satya

 

[mister_rf]

You may add some external resistors, see the example I have posted here:
https://www.edaboard.com/threads/248773/#post1065120