Hi guys, can you please help here.

I need to design a wein-bridge oscillator to generate 40 KHz frequency. I need it for my ultrasonic range finder project. thanks in advance.

 

I was going to ask why a wein-bridge but I guess toy want a simple way to produce a sine wave, is that right?
There seem to be plenty of tutorials out there with formulas to calculate freequency.
this is the one i found first:-
http://www.electronics-tutorials.ws/oscillator/wien_bridge.html

I will be keeping an eye on this thread so I can learn.

 

use a Ca3140e op amp see page 16 of data sheet

http://www.intersil.com/content/dam/Intersil/documents/fn95/fn957.pdf

a dual version is a ca3240e

 

I have an E-Book that will discuss this topic and more also http://www.ti.com/lit/an/slod006b/slod006b.pdf

 

Make sure the op amp bandwidth is greater than 80Khz because bandwidth falls off fast in voltage op amps.