S, quiz, blog and videos of electronic device & circuits. For electronics engineering. It almost cover all topics which are indexed chapter wise. Chapter 1. Semiconductor device. 1. Semiconductor device. 2. Theory of P-N junction. 3. Temperature dependence and break down characteristics. 4. Junction capacitances. 5. Zener Diode. 6. Varactor diode. 7. PIN diode. 8. Led.