Zener diode diagram. Transistor-Zener Diode Regulator Circuits. NPN* Active/Linear Mode Question | Page 2 | All About Circuits. Transistor Biasing Calculations | Bipolar Junction. Simple Overvoltage Protection Circuit using Zener Diode. NSM6056M: NPN Transistor with Zener Diode - Onsemi. NSM6056M - NPN Transistor with Zener Diode - Onsemi. US6320452B1 - Floating power supply using dual npn trans..