Op Amp circuit for a sine wave

Thread Starter

EvilGenius2222

Joined Sep 16, 2018
9
I need to build an op amp circuit to build a 2 V P-P sine wave, 1 KHZ frequency with a 1.5 V DC Bias. Can anyone help with the design of the circuit im not entirely familiar with op amps. Thank you.
 

AlbertHall

Joined Jun 4, 2014
12,623
A phase shift oscillator:
upload_2018-9-16_9-45-8.png
A wien brdge oscillator:

A wien bridge oscillator with amplitude stabilisation for lower distortion:

What level of distortion would be acceptable for this sine wave?
 

Thread Starter

EvilGenius2222

Joined Sep 16, 2018
9
The 1.5 Bias, you mean you want the sine to be offset from ground
by 1.5V ?

Something like this ?
Yes.
View attachment 159986

Regards, Dana.
A phase shift oscillator:
View attachment 159983
A wien brdge oscillator:

A wien bridge oscillator with amplitude stabilisation for lower distortion:

What level of distortion would be acceptable for this sine wave?
Im not quite sure about distortion just like im not one hundred percent about the theory behind the circuit.
 

Thread Starter

EvilGenius2222

Joined Sep 16, 2018
9
Is this a Homework?
If not then what's the load and purpose for this circuit?
This is an independent study project , and that was the only info i was given. I've never used/herd of op amp before so i did a lot of research online and i get the gist im just having a difficult time correlating it to the info i was given.
 

MrAl

Joined Jun 17, 2014
13,677
Hi,

An op amp is a device that amplifies the difference between two signals. It is almost always used with a feedback circuit to perform linear amplification which is used for different types of circuits.
For the phase shift oscillator it is used to provide a certain amount of gain as well as 180 phase shift.
BTW the phase shift oscillator also needs to have some form of amplitude stabilization added to it which is usually some kind of clipping. The gain must be kept at a certain value in order to maintain oscillations yet not cause the output to ramp up and saturate.
 

PsySc0rpi0n

Joined Mar 4, 2014
1,786
I am interested in this circuit. I built the schematic on LTSpice but I have no idea of component values like resistors and capacitors. For the transistirs, would 2N222 (or 2N222A) suit the application?

I was reading somewhere about the RC series and parallel setup for the Wien basic bridge and about the resonant frequency. So I tried 1kΩ resistors and 1uF capacitors for a 160Hz resonant frequency. Then I simulated in LTSpice with a Small AC signal and Decade type from 1Hz to 100Khz. Apparently, the resonant frequency is about 90Hz.
I'm probably doing it wrong, so I would like to start from here.
I have attached the circuit.
 

Attachments

PsySc0rpi0n

Joined Mar 4, 2014
1,786

Thread Starter

EvilGenius2222

Joined Sep 16, 2018
9
Like i said i get the gist of OP Amps i just am a little stuck on applying the given information i received to a circuit. Like where does the bias come in the circuit?
 
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