Donor and Acceptor Impurities Speech circuit Current Density in Metal and Semiconductor PN Junction Bias Intrinsic Semiconductor N Type Semiconductor Energy Bands of Silicon Ultrasonic ranging Intrinsic Silicon and Extrinsic Silicon Photodiode Laser Diode Vacuum Diode Diode Test Avalanche Diode Gunn Diode Varactor Diode Power Diodes Diode Reverse Recovery Time Laser Types and Components PIN Photodiode Tunnel Diode PN Junction Diode Diode Characteristics Resistance of a Diode Diode Current Equation Ideal Diode PIN Diode Darlington Transistor PNP Transistor NPN Transistor Transistor Working Principle BJT as Switch Applications of BJT DIAC TRIAC Types of Transistors Transistor Characteristics Transistor Manufacturing Techniques Transistor as an Amplifier Phototransistors Current Components in a Transistor White Light Emitting Diode LED Work LED JFET Characteristics Electric transmission Transmission Lines Parameters、Types 、 Theory Short Transmission Line Medium Transmission Line