Dirtbaby D2 curiosity

[controlFreak]

Hello again! Really dug this extra filtered pt2399 circuit. Built mine with a fx loop and master volume.

Just a curiosity about the D2 LED across pins 7 and 3. the build doc says its there to reduce distortion at the input... but Pin 7 is not the input and pin 3 is ground.

So whats really going on here?

And can this be used to some benefit/effect in any other PT2399 circuit?

[midwayfair]

Read the "how it works" section in here, starting near the block quote on page 7.

[somnif]

Short version: The LED acts like a crude zener to cap the voltage at pin 7 to about 2V, helps reduce nasty in-chip distortion from beefy signals (say from boosts/distortions/active pickups in front of it).

(Pin 7 is a wee bit of a mystery beyond a label of "current control 1" in the data sheet, and a connection to the "DEM" circuit block internally)

[controlFreak]

Read the "how it works" section in here, starting near the block quote on page 7.

Right, re-read the OP, in it I rephrase the info from the build doc. I'm trying to get more info and learn more about how and why.

I seems we've hit datasheet bedrock tho (thanks somnif!)... control current input...hmm. I will dig into the datasheet.

[midwayfair]

Read the "how it works" section in here, starting near the block quote on page 7.

Right, re-read the OP, in it I rephrase the info from the build doc. I'm trying to get more info and learn more about how and why.

I seems we've hit datasheet bedrock tho (thanks somnif!)... control current input...hmm. I will dig into the datasheet.

I'm not sure you actually looked at what I linked to.

[controlFreak]

sorry! I didn't see the link on the first read. great info, thanks!