madbeanpedals::forum

Projects => General Questions => Topic started by: Aleph Null on February 07, 2024, 04:29:12 PM

Title: OTAs, How do they work?!
Post by: Aleph Null on February 07, 2024, 04:29:12 PM
(http://i1.kym-cdn.com/entries/icons/original/000/002/395/magnets_c.jpg)

I'm trying to understand the LM17300, but haven't been able to find much information beyond the data sheet. Explainer articles or videos all insist on using a split power rail and don't do much in the way of practical examples. Does anyone have a source that shows how to use an OTA as an amplifier (as opposed to a resistor, or in a filter)? I'm especially interested in examples of using an OTA without a split power rail.

Thanks, all. I know someone here must have some experience.
Title: Re: OTAs, How do they work?!
Post by: lrgaraujo on February 07, 2024, 08:09:23 PM
There are some application notes for the ca3080 here
https://www.experimentalistsanonymous.com/diy/Datasheets/AN6668.pdf

A ross-style compressor is an application like you want (single power supply and amplifier). E.g. https://www.madbeanpedals.com/projects/_folders/Compressor/pdf/Kompromat.pdf.

Spaceman Effects Aphelion is also a very interesting ota-based pedal (diy board and schematic here https://www.deadendfx.com/product/anticarus)
Title: Re: OTAs, How do they work?!
Post by: Aleph Null on February 07, 2024, 09:31:17 PM
Thanks. I knew the Ross had an OTA in it, but I thought it was being used as a voltage-controlled resistor—I should have looked close at the schematic. The Aphelion actually appears to be doing what I want to do; saturate the OTA. I'll definitely be looking into that.