Adding a LED drivers to TH AD Enveloppe Generator

[Dozemuisc]

Hello!

I would like to add two leds to this design, (one that light up during the attack and one that light's up during decay).

We don't have much space left on the PCB so we would like someting with as few components as possible.

Would this design work?

Thank you very much!

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[Grumble]

The attack led “might” work when placed before the diode directly to pin 3.
Since pin 7 is an open collector (it can only sink, not source) this will not work, worse: the whole circuit will stop working because the timing capacitor will not charge due to the low impedance formed by the R+LED
You could try to place this led + resistor from vcc to pin 7, with the cathode towards pin 7.

[Dozemuisc]

Allright thank you very much I'll try to prototype that!

[PHOBoS]

[Grumble]

[richardc64]

Add a diode and move Decay to pin 3. That'll free Discharge to sink the Decay LED.

[PHOBoS]

[JovianPyx]

[Dozemuisc]

Wow thanks I learned a lot of stuff.

Mainly that it's too complicated to do. I'll just stick with one LED.

It should work with this design :

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[PHOBoS]

I'd add a resistor in series and then connect it straight to pin 6.