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Transistor voltage regulator and ripple filter circuits explaine…

Transistor voltage regulator and ripple filter circuits explaine...

Let's delve into these circuits to see how they work. I bread-boarded a transistor regulator near the end of the video.


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Tags: transistors

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  1. Date: June 18, 2014 at 00:13
    Author: HillOrStream

    Not going to soup up the audio circuits too? Better caps, low noise transistors or maybe a chip?

  2. Date: June 18, 2014 at 01:16
    Author: CoolDudeClem

    Good video and nice explanation, it might have been worth mentioning that its best to not have too much difference between the input and output voltages, the less difference there is the more efficient it will be and the transistor will run cooler.

  3. Date: August 2, 2014 at 16:19
    Author: Nukemaster

    Would combining the 2 work?
    So the regulator feeds the ripple filter.

    I know it would cause more voltage loss, but a higher reference voltage could solve that.

  4. Date: January 29, 2015 at 03:02
    Author: N8ZU

    your ripple filter also know as a capacitor multiplier, the capacitance is multiplied by the gain or hfe of the transistor.
    gr8 job merci beaucoup

  5. Date: June 17, 2015 at 21:13

    So, what's the formula for the voltage that you want to regulate? If I want my output voltage at 30volts, then I use a 30volt zener and what resistor? This probably has a really obvious formula.

  6. Date: August 14, 2015 at 18:26

    The more voltage my transformer puts out the more transistors I need because to high of à voltage on one transistor would burn it out right?

  7. Date: September 8, 2015 at 03:01
    Author: Rook E

    At dynamic input power will the transistor regulate to specific voltage and up the amperage if the input voltage exceeds the transistor voltage? As long as the heat sink is right..or would it typically burn out..

  8. Date: September 21, 2015 at 17:17
    Author: Smoke

    I tried it with a 220ohm resistor and the resistor and the zener blew up..Then i tried with a 470ohm resistor and the circuit worked fine,but the output was very unstable if a small current was aplied (~20ma)

  9. Date: November 23, 2015 at 10:56
    Author: talastas789

    i have problem bro that can be power a very!! very low watt amp like 3 watt?? that the power is 6-7 volt only

  10. Date: March 8, 2016 at 02:02
    Author: UFO1997

    What about in the technics Integrated amplifier SU-V9;  the circuit in charge of turning the  stereo on?  How can I determine  how much  the voltages of zener diode should be. Could you find out for me.    And if I use a filter, is that filter has to be a bipolar !?

  11. Date: July 31, 2016 at 14:34

    So basicaly, since the voltage at the base is fixed at 5 volts, if Vin increases, Ib increases and IE increases, causing VE to increase from let's say 5 to 10volts. Thus you need a base voltage of about 10,7 volts and since VB is fixed at 5volts, the transistor would lack the required voltage to turn on and it will turn off. Meaning that VE must not increase 5volts and remain the same. Is this it??????

  12. Date: September 5, 2017 at 11:58

    Thank you, I've been wondering how these transistor + zener diode circuits on power supplies worked for ages.

  13. Date: September 15, 2017 at 01:38
    Author: Joshua Davies

    I really like the way you explain this circuit. I do have one question though. My.current understandkng is that the load voltage is equal to Vb minus the voltage drop across the transistor. However, what would the effect be of some addition diodes across between the power supply and the collector?

  14. Date: January 2, 2018 at 16:16

    The capacitor multiplier/ripple filter circuit is also a great way to replace batteries with a wall wart in most cases.
    If you replace the Zener diode in your first circuit with an adjustable shunt regulator, add a resistor between the emitter and load, then connect the reference of the shunt regulator between the new resistor and load, you will have a current regulator. The schematic for this is in the TL431 datasheet from TI.

  15. Date: July 2, 2018 at 12:50
    Author: mrsemifixit

    So regardless of how much voltage is on the input and subsequently the collector of the transistor, the Zener prevents that higher voltage from passing from the collector to the load? Base voltage control keeps collector voltage from exceeding?

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