Do you protect your outputs?

I'm not a module designer, but I would say that it depends what your module does and whether your output is always an output or can also be used as an input.

For an oscillator or filter for instance it makes sense to protect the output, because it makes absolutely no sense to send voltage into it.

A weird and super interesting example of where the line blurs is the 3vcswitch where the two inputs can be outputs and the one output can be an input and the whole flow can work in reverse.

wiki.aemodular.com/pmwiki.php/AeManual/3VCSWITCH

I see, I put diodes on each of my outputs hoping those would block input voltages, is that a bad design?

This is only good when your outputs are digital signals (eg triggers, or +5V/gnd). In case of audio out this will usually not work!! (because audio is AC, the diode distorts the signal). In general, diodes in your audio chain are only good if you really want clipping/distortion/ladder filter effects. Not for clean audio. But I suppose this is about your AEclidiaen module, in which case I think it will work just fine.

Also, considering AE only runs on 5V, the diode drop of 0.7V can be tricky to deal with. I think most envelopes will accept a 4.3V trigger/gate instead of 5V, but I still believe the closer to 5V the better.


For my own modules, I myself looked up the MCP602/4 maximum current output & power, and calculated that if you put in a 220 ohm resistor (1/4W) at the output, you should be fine. The maximum current when you would short the module to ground, would be 5V/220 = 22.7 mA. This is fine for the MCP opamps. Best is to look up the datasheet of your output stage IC and decide according to its max ratings. I think for example that CD40xx logic IC's can provide less amps than the MCP opamps, in which case a larger resistor would be needed.