1. How do v2 and V3 of this circuit achieve similar functions as a Zener tube?
2. Is the output voltage of this circuit: Uin*[R1/(Rp+R2+R3)]+0.7V (Vbe of V1)? ? ?
Emilia 發表於 October 20, 2020
The function of the voltage regulator tube is replaced by the forward voltage drop of the V2 transmitting junction.
The forward voltage drop of the V2 transmitting junction is not as stable as the voltage regulator tube, so this circuit has poor voltage regulation characteristics.
Arthur 發表於 October 20, 2020
It's easy to understand things other than V1 R1 as a voltage regulator.
Clayton 發表於 October 20, 2020
As the "sofa" and "bench" said, this is the truth.
Now you can use a TL431 to replace the adjustable regulator tube composed of V2 V3, and the output voltage is stable.
Aurora 發表於 October 20, 2020
This is a regulator tube plus a secondary current, not a negative feedback regulator circuit, the combination of V2 and V3 acts as a regulator tube.