Question 150: Semiconductors and Logic Gates

Question

In the figure, given that V
BB
supply can vary from 0 to 5.0 V, V
CC
= 5V, $\beta $
dc
= 200, R
B
= 100 k$\Omega $, R
C
= 1 k$\Omega $ and V
BE
= 1.0 V. The minimum base current and the input voltage at which the transistor will go to saturation, will be respectively :
![](https://imagex.cdn.examgoal.net/fyMEvmcRHXROgWndy/dU1yL3CcK3wKWK6ZjEOUMwLS6lS1b/WKpZvayRCA6jqhPJS4tZ0h/image.png)

Accepted Answer

At saturation, V
CE
= 0
V
CE
= V
CC
$-$ I
C
R
C
$ \Rightarrow $  I
C
= ${{{V_{CC}}} \over {{R_C}}} = 5 	imes {10^{ - 3}}\,A$
Given
$\beta $
dc
= ${{{{m I}_C}} \over {{{m I}_B}}}$
I
B
= ${{5 	imes {{10}^{ - 3}}} \over {200}}$
I
B
= 25$\mu $A
At input side
V
BB
= I
B
R
B
+ V
BE
= (25mA) (100k$\Omega $) + 1V
V
BB
= 3.5 V

Answer

20 $\mu $A and 2.8 V

Answer

25 $\mu $A and 2.8 V

Answer

20 $\mu $A and 3.5 V

Answer

25 $\mu $A and 3.5 V

Semiconductors and Logic Gates

In the figure, given that V BB supply can vary from 0 to 5.0 V, V CC = 5V, \beta dc = 200, R B = 100 k\Omega , R C = 1 k\Omega and V BE = 1.0 V. The minimum base current and the input voltage at which the transistor will go to saturation, will be respectively :

Choose the correct answer: