Triangle Wave Generator Help

[cyaniccypher]

I have a square wave with a variable frequency between 300khz and 360khz (Using LMC6908) that i need to convert into a triangle wave.

What is the best way to perform this task to keep the peak to peak voltage of the triangle wave constant.

Also my square wave is between 0 and 5V while my triangle wave needs to be between -5V and 5V referenced at 0V.

 

[sztibi82]

The easiest way to obtain from square wave triangle wave is by integrating it. Since the bandwidth is narrow, try to search for integration circuits using op-amps.
To have the -5+5V range first offset signal and then amplify it. For offset use adder circuits with a negative reference, and then amplify the resulted signal to get the required range.

 

[crutschow]

An integrator will give you a varying output voltage with frequency. The only way I can think of to keep the output voltage constant is to use an AGC circuit on the integrator output.

It would be easier to generate the triangle wave directly using an integrator and a comparator in a feedback loop. That way the output is essentially independent of frequency.

 

[cyaniccypher]

An integrator will give you a varying output voltage with frequency. The only way I can think of to keep the output voltage constant is to use an AGC circuit on the integrator output.

This i know that is the reason behind this post.

It would be easier to generate the triangle wave directly using an integrator and a comparator in a feedback loop. That way the output is essentially independent of frequency.

I have a circuit like this (see attachment) but how do I make the frequency variable over some predetermined range like +-10%

Thanks

 

[FvM]

By varying R6 you change the frequency and keep the amplitude. The present circuit has a frequency of about 0.5 MHz.

 

[godfreyl]

I have a square wave with a variable frequency between 300khz and 360khz (Using LMC6908) that i need to convert into a triangle wave.

What is the best way to perform this task to keep the peak to peak voltage of the triangle wave constant.

You could use a variable frequency triangle wave generator locked to the input signal with a phase locked loop.

I have a circuit like this (see attachment) but how do I make the frequency variable over some predetermined range like +-10%

In your circuit you could put some kind of clamp between U2 and R6 to limit/control the amplitude of the square wave current going into U6. A circuit based on voltage controlled current sources would probably be better though.