I've been trying to build a function generator with the ICL8038 chip I found on eBay. There are a few interesting schematics on the net and I've made a couple on my bread board. The datasheet says the chip is able to provide stable wave forms up to around 200 KHz. That is accurate for the triangle wave and up to a point for the sine wave as well. I've been having big problems with the square wave however. It looks fine up to around 1000 Hz, after that, the top left of the square starts drooping until it eventually ends up as a saw wave. So far, I'm just talking about the signal coming directly out of the 8038 on pin 9 before it goes into op amps and so on. I'm using a dual rail +12v 0 -12v power supply to run the chip. Does anybody know if there's a way to fix this using external components or is it just the limitations of the chip itself?
I've attached a few photos I took of the square wave on my ancient oscilloscope
I've attached a few photos I took of the square wave on my ancient oscilloscope
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