Voltage Regulator Design with BJT Darlington Transistors and Zener Diodes

Design of a minimal Regulated Voltage Supply is discussed in this video along with the Analysis and Practical choice of parameters for a near-minimal component power supply. For more circuit examples please see    • Voltage Regulator Design with Op Amp ...   and    • Voltage Regulator design with Op Amp ...   .
Note that the analog circuit discussed in this example does not require Op Amp. The input unregulated voltage is varying considerably in the range of 20 to 30 volts. This minimal regulator design requires two Zener Diodes, total of four Bipolar Junction Transistors in the form of one BJT Darlington Transistor pair and one semi Sziklai transistor pair and one towered transistor pair. The bottom Zener Diode with 5.1v Zener break down voltage and minimum Zener current of 1 mA sets the reference voltage for the regulated 16v at the output. The circuit components are designed to support up to 2A maximum current for the output resistor load. A combination of Kirchhoff's circuit laws and BJT current gains is applied to analyze and design this voltage regulator circuit.