Four%20Layer%20P-N-P-N%20Switching%20Devices%20%28Shockley%20Diode%29%2C%20Lecture%20-%2011%2C%20TDC%20Part%20-%20II%2C%20Paper%20-%20III%2C%20%28Group%20-%20A%29%2C%20Chapter%20-%204%2C%20By%20-%20Dr.%20Niraj%20Kumar.pdf Department Electronics Semesters UG - 2nd Year