Electronics, PCB Design and PCB Layout Daycounter, Inc.
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Variable Zener Circuit
Variable Zener Schematic

See our other Circuits.

A zener diode acts like a normal diode, blocking current when it is reverse biased until a threshold voltage is surpassed, then it conducts.  Zener diodes are often used in  voltage regulators. 

The circuit below simulates a zenor diode and is programmable with a resistor divider network.  The zener voltage is equal to:

Vz= (R2*V)/(R1+R2)+Vbe

Where Vbe is the voltage drop from the emit to the base of the transistor, and which is normally about 0.6V

Variable Zener Schematic

Variable Zener Schematic


Do you need help with an electronics design?  Daycounter provides contract electronics design services. Contact us to give you a quote on your electronics design project. 


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