# Base emitter voltage and collector current

by ranju
Tags: base, collector, current, emitter, voltage
 P: 91 Does decrease in value of base-emitter voltage decreases collector current..?? As I studied that decrease in base-emitter voltage of some part of signal to lesser ammplification of that part due to smaller current..but how base emitter voltage is leading to less collector current.. because if base-emitter voltage decrease , base current increase which further increase collector current..
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P: 5,475
 Quote by ranju Does decrease in value of base-emitter voltage decreases collector current..??
Yes.

 As I studied that decrease in base-emitter voltage of some part of signal to lesser ammplification of that part due to smaller current..but how base emitter voltage is leading to less collector current.. because if base-emitter voltage decrease , base current increase which further increase collector current..
If VBE decreases, base current decreases. It's a p-n junction, so the characteristic is that of a p-n junction diode. If the forward voltage increases, the forward current increases.
 P: 91 But base-emitter voltage is a barrier voltage.. so if it decreases , base current should increase..!!!
PF Gold
P: 2,732
Base emitter voltage and collector current

 Quote by ranju But base-emitter voltage is a barrier voltage.. so if it decreases , base current should increase..!!!
No. NascentOxygen has given you the correct answer. Consider the Base-Emitter Voltage curves:

Check out these Base-Emitter Junction Details.
 P: 91 But is'nt there any logic behind it...?? because if we see this equ. Ib=Vb/Rb - Vbe/Rb so from this equ. it can be seen that if Vbe increase base current decrease..!!!
PF Gold
P: 3,740
have you ever run across the formula for current through a junction,
I=eqv/kt
where v would be your Vbe ?
That's what dlgoff's graph is showing you.

 because if we see this equ. Ib=Vb/Rb - Vbe/Rb so from this equ. it can be seen that if Vbe increase base current decrease..!!!
that involves not only Vbe but an external Vb and an external Rb.