Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Wien Bridge oscillator

Status
Not open for further replies.

stobbz

New Member
Hello, I'm doing some work with Wien Bridge oscillators and having a look at some of theory.

Apparently oscillation occurs at the resonant frequency = 1/2*PI*R*C

However, if you apply the Barkhausen criteria for oscillation you get a completely different expression for oscillation frequency, in my case f = 1/R*C

What is the difference between the two?

Thanks!
 
Stare at this:

At what frequency is the phase shift exactly 0 degrees?

What is the loss (in db) at that frequency?

Relate that to the formulas you posted.
 

Attachments

  • DF162.png
    DF162.png
    33.2 KB · Views: 337
Last edited:
Notice what happens if the Wien network is connected to a non-inverting amplifier with gain slightly higher than 3 (9.54db), and is given an initial perturbation.
 

Attachments

  • DF162a.png
    DF162a.png
    37.5 KB · Views: 347
Thanks a lot MikeMl, those were really helpful. I feel stupid for asking the question now, having woken up feeling (relatively) refreshed, I can see that one expression simply gives the oscillation frequency in Hertz and the one I derived gives it in Radians... D'Oh!

Thanks again MikeMl!
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top