wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

When a p-n junction is reverse biased, the current becomes almost constant at 25μA. When it is forward biased at 200meV, a current of 75μA is obtained. Find the magnitude of diffusion current when the diode is (a) unbiased (b) reverse-biased at 200mV and (c) forward-biased at 200mV.

Open in App
Solution

Given,
p-n junction is reversed biased.
i1=25μA
V=200mA
i2=75μA
(a) unbiased condition.
Diffusion current=Drift current=i1
Diffusion Current=25μA
(b) Reversed biased condition at 200mV
On the reverse biasing the diffusion current becomes zero.
(c) Forward biased condition at 200mV
At,Forward biased, the actual current be i
So,
i=Drift Current= Forward biasing current.
ii1=i2
i25μA=75μA
i=(75+25)μA=100μA
Diffusion current forward biasing becomes 100μA at 200mV

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
PN Junction
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon