Here's an 8HP envelope generator based on the AS3310 chip. It's very similar to the Polyphonic/Quad ADSR EG Module, because that was the starting point. I found myself needing additional ADSRs and that was the easy way to make one.
To fit in 8 HP the circuit is split onto to PCBs. As with all of my designs, the signals in/out are 0-10V.
The trigger input and switch is a new input on this (compared to the Quad ASDR). It appears to work; however, I haven't focused on testing it.
Version one of the PCB had the out/release pins reversed on a header so the images below show rework for that. I had to rework and reorder another design so I quickly made a v1.1 for this at the same time and that corrects this issue.
v1.0 PCBs in these photos require rework, but v1.1 is otherwise identical.
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