ટ્રાન્સિસ્ટર એ એક સેમીકન્ડક્ટર ઉપકરણ છે, જે સિગ્નલ એમ્પ્લિફાય (Amplify) અને સ્વીચ (Switch) માટે ઉપયોગ થાય છે.
1️⃣ ટ્રાન્સિસ્ટર કેટલાં પ્રકારના હોય છે?
ટ્રાન્સિસ્ટર મુખ્યત્વે શ્રેણી અને પ્રકાર પ્રમાણે વર્ગીકૃત થાય છે:
1️⃣ Bipolar Junction Transistor (BJT)
પરિભાષા: બે PN જંકશન સાથે બનેલું ટ્રાન્સિસ્ટર
Structure: NPN અને PNP
Symbols:
NPN:
C
|
|
B|---->E
PNP:
C
|
|
B<----E
Working: Current controlled device – Base current controls Collector-Emitter current
Use: Amplifiers, Switches, Oscillators
Sub-types of BJT:
NPN: Majority carriers = Electrons
PNP: Majority carriers = Holes
2️⃣ Field Effect Transistor (FET)
પરિભાષા: Voltage controlled device, high input impedance
Structure: Source (S), Gate (G), Drain (D)
Types:
Junction FET (JFET) – N-channel / P-channel
MOSFET (Metal Oxide Semiconductor FET) – Enhancement / Depletion type
Symbols:
N-channel MOSFET:
D
|
|-----> S
G
P-channel MOSFET: Reverse polarity
Use: Switches, Digital Circuits, Power Control, Amplifiers
3️⃣ Special Transistors
Darlington Transistor
Two BJTs in one package
Very high current gain
Use: Relay driving, high gain amplification
Phototransistor
Light-sensitive transistor
Use: Light detection, IR sensors
Unijunction Transistor (UJT)
Used in oscillators, timing circuits
Switch like operation
IGBT (Insulated Gate Bipolar Transistor)
Combination of BJT and MOSFET
High power applications
Use: Motor drives, inverter circuits
4️⃣ ટૂંકું સારાંશ
Type | Controlled By | Symbol | Use |
BJT (NPN/PNP) | Current | B, C, E | Amplifiers, Switches |
JFET | Voltage | G, D, S | High input impedance, Amplifiers |
MOSFET | Voltage | G, D, S | Switching, Power Electronics |
Darlington | Current | B, C, E | High gain amplification |
Phototransistor | Light | B, C, E | Light sensors, IR detection |
UJT | Voltage | B1, B2, E | Oscillator, Timing circuits |
IGBT | Voltage | G, C, E | High power switching |
�� ટિપ:
BJT – Current Controlled Device
FET/MOSFET – Voltage Controlled Device
IGBT – High power applications
