ECE231 Area3

Introduction to

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Operational Amplifier Circuits

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¥o¥¥÷÷it÷÷!i⇒¥I¥I¥E son:*:*...→¥ ions in depletion

:*:#If Deme; onn i'Ee regio

↳ Lack of conductingcarriers

.

Lecture 20 : 2/25/2020

i.n

o

Electricfield CE't

- Created by positive negative ions in depletion region- Stops diffusion of majority carriers

CIDIFF - flow of majority charge carriers )- Swept minority carriers across boundary

CI drift C Is ) - Flow of minority Charge carriers )

② Drift current [holes ④ : n - type → p - type

,I drift

s,¥o¥Ego¥¥I¥ofelectrons -0 : p - type -2 n - type

-7 IDIFF

Diode behaviour from Pn junction-

- Not

① Equilibrium open circuit )o -

P n- o

IDIFFI I drift ) IDFdrift hepepietion

Region

or:÷÷÷÷÷*÷¥i÷:¥¥¥¥

⇒ I net= - Is Gato ration -

current ) Wider depletion region

③ Forward Bias

IDIFF→① '# o

← Idris ¥n

Ip µµn

-1E- Is @VNT- I ) -0 to

use" "

Forward

µ⇒Idris tchwinan.ee?aeE!entionegregign

Equilibrium Iot = I drift

÷,F¥¥ ,Reverse

IDIFFSI drift