This document discusses several electronic devices and circuits. It describes n-type semiconductors, center tap full wave rectifiers, and their disadvantages. Zener diodes are introduced as voltage regulators, explaining their equivalent circuit and characteristics for stabilizing voltage. The concepts of faithful amplification, proper biasing conditions for transistors, and voltage divider bias methods are summarized. The voltage divider bias circuit and equations for collector current and collector-emitter voltage are derived.

1. MECHANISM OF
ELECTRONIC DEVICES
PRESENTED BY: MOUNTAIN MOVERS
MD. ASHRAFUL ISLAM TALUKDAR
MD. SHAKIL
RAKIB HOSSAIN
ABU KAISER MOHAMMAD MASUM
FOWJAEL AHAMED

2. N TYPE SEMICONDUCTOR

3. CENTRE TAP FULL WAVE RECTIFIER
Peak Inverse Voltage:
PIV=2𝑉𝑚
Disadvantages:
(i) Difficult to locate.
(ii) The dc output is small.
(iii) High peak inverse voltage

4. ZENER DIODE
What is Zener diode?
Equivalent circuit of a Zener diode
 Zener voltage
 Zener Resistance
Characteristics of a Zener diode
 Zener diode as voltage stabilizer
 Input voltage increases
 Load resistance decreases

5. FAITHFUL AMPLIFICATION
 Definition
 Basic conditions:
 Proper zero signal collector current
 Proper minimum base-emitter voltage (𝑉𝐵𝐸)
 Proper minimum collector-emitter voltage (𝑉𝐶𝐸)
Proper zero signal collector
current
Proper minimum base-emitter
voltage (𝑉𝐵𝐸)
Proper minimum collector-emitter
voltage (𝑉𝐶𝐸)

6. VOLTAGE DIVIDER BIAS METHOD
Circuit Analysis:
1. 𝐼𝑐
2. 𝑉𝐶𝐸
Collector Current IC:
I1 =VCC ̸ R1+ R2
So, voltage across resistance R2 is
V2 = (VCC ̸ R1+ R2) R2
Appling KVL to the base circuit of the Fig
V2 = VBE + VE
or, V2 = VBE + IERE
or, IE = (V2 - VBE) ̸ RE
Since, IE ≈ IC
∴ IC = (V2 - VBE) ̸ RE
Though IC depends upon VEE but in practice
V2 >> VBE, so that IC is practically
independent of VBE.
Collector-emitter voltage VCE:
Applying KVL to the collector side.
VCC = ICRC + VCE + IERE
= ICRC + VCE + ICRE [Because
IE = IC]
= IC (RC + RE) + VCE
VCE = VCC – IC (RC + RE)