Hello,

I am looking for an IC that generates triangular wave with frequency range from 1KHz to 100KHz. I looked at many ICs and the thing I didn't like is that the frequency is set either through a fixed resistor or a pot.
Is there a triangle wave generator chip whose frequency can be set/adjusted through an analog voltage directly.

Thank you.

 

I don't think so. There used to be a handful of function generator chips, but they have been obsolete for a decade or more. They are available on auction sites for princely sums. My suggestion is to build one from basic parts by integrating the output of a square wave VCO.

You might also try DDS (Direct Digital Synthesis) with a first order hold.

 

My suggestion is to build one from basic parts by integrating the output of a square wave VCO.

+1 Another, sloppier approach would be to use the voltage on top of a 555's timing capacitor. IT's not quite a triangle but awfully close for most uses.

 

or, you can get this IC to use as a triangle wave generator, >>> http://www.maximintegrated.com/app-notes/index.mvp/id/4362

and here is some more reading on the subject>> http://www.ni.com/white-paper/13238/en

 

Do you need a symmetrical triangle wave, or will a linear ramp work? There are 555 circuits that will do this.

Here is what the earlier post was alluding to:

 

yes, I am looking for a symmetrical tri-wave, to be used a part of a PWM generator.

 

PWM does not need a symmetrical triangle wave.

Pulse Width Modulation

Something I wrote for the AAC book.

 

http://www.intersil.com/content/dam/Intersil/documents/fn28/fn2864.pdf

Look at figure 10, page 8

.check them out on Ebay http://www.ebay.com/sch/i.html?_nkw=8038+ic

 

I have used this AD5932. It also looks like NTE is selling rebranded ICL8038 under the name of NTE864. It's daylight robbery to charge that amount of money for that chip although
http://www.datasheetdir.com/NTE864+download

 

Especially when there are many ways to skin this cat. If the OP finds what I have shown unacceptable I can dig up other circuits. Triangle waves are both easy and bread and butter to electronics.

 

http://www.intersil.com/content/dam/Intersil/documents/fn28/fn2864.pdf

Look at figure 10, page 8

.check them out on Ebay http://www.ebay.com/sch/i.html?_nkw=8038+ic

It was the 8038 and the Exar 2206 that I was referring to. I would be very suspicious of the $3.99 price. It could just as well be an empty lead frame in a plastic package. It would not be the first time this has happened.

 

yes, I am looking for a symmetrical tri-wave, to be used a part of a PWM generator.

So why do you need a voltage controlled frequency?
PWM is normall fixed frequency with variable duty-cycle.

 

So why do you need a voltage controlled frequency?
PWM is normall fixed frequency with variable duty-cycle.

well, both the PWM frequency and duty cycle need to be controlled, because this PWM will control a high voltage pulse generator, which need to operate at different frequencies as well as different duty cycles.

 

The ICL8038 could be used as a VCO. And the NTE IC I pointed you to. Is in fact a ICL8038. If this is some one of i kind project. I say why not get some ICL8038 from EBAY. Better than getting the same chip from NTE