Transistors and zener diodes are components that are related because they are both made from semiconductor materials, but what differentiates the two is how they work.
Zener diodes function as voltage stabilizers and their installation is different from ordinary diodes, namely they must be installed in reverse.
Circuit Calculation Analysis
Vi = VR1 + Vz
Vi = Vo + VCE
Vi = (IR1 . R1) +Vz
Vi = [(IB+Iz)R1]+Vz
Vo = VRL
Vo =Vi -- VCE
Vo = Vz -- VBE
Vo = (Vi -- VRI ) -- VBE
Conclusion:
Based on observations/research, it turns out that the output voltage is stabilized by the zener diode as the maximum output voltage = VDz
Basic DC Regulator Circuit
HK. Kirchoff 1
The sum of the currents entering a branch point is equal to the sum of the currents leaving that branch point.
Kirchoff's Law 2
The EMF (electromotive force) in a voltage source causes electric current to flow along a circle (loop) and the electric current that encounters resistance causes a decrease in voltage (I,R) so that it can be written with the equation:
∑E + ∑IR = 0
This equation is Kirchoff's second law which states "the algebraic sum of the voltage changes surrounding a closed circuit is 0" .
Netizens
Q1:
- ONLINE SECRET Sep 5, 2014, 05:26:00 It would be more complete if it was accompanied by an example of the calculation, bro. Awesome.
- HAERUL HAMKA Apr 15, 2016, 11:07:00 AM What if it is applied to a motor coil, won't the zener diode burn out? The motor coil voltage is unstable, around 12-25 volts?
A1:
Okay, bro, thanks for your input,,, and I will update it again soon.
The zener diode will not burn out, because in its use it will never be alone, but always collaborate with the transistor, so that the transistor works to control the source voltage, while the transistor is controlled / locked by the zener diode.
In the voltage stabilizer circuit above, the component that has the potential to be damaged due to burning is the transistor, because the one that comes into direct contact with the source voltage is the transistor. Therefore, the selection of specifications must be appropriate, where it will be worked on.
For example, if you want to use it for voltages up to 25 volts, then one of the transistors that can do that is INI .