NoDrivingSource

Getting the "Net ... has no driving source (Pin ...)" error ?

The Altium Knowledge Base (Protel Knowlege Base)
http://www.altium.com/forms/kb/kb_item.asp?ID=4157
briefly explains what that means.

The vast majority of the time, it is obvious how to fix the schematic; then the error goes away. (The net needs to be driven by *something*, and you haven't connected it yet or it got accidently disconnected).

But in one (what I assume fairly common) case, it's not obvious (to me at least) what the Right Way to fix it is:

I have an op-amp filter, with a blob of resistors, capacitors, etc. between the output of one op-amp to the input of the next op-amp. I'm getting this error on the net connected to that input pin of the op-amp.

(The "Circuit Simulation\Peak Detector\Peak Detector.PRJPCB" and "Reference Designs\Peak Detector\Peak Detector - Multi channel.PrjPcb" examples that comes with Protel have this problem).

The schematic looks OK to me.
What is the Right Thing to do to fix this error ?

• Plop down a No-ERC red X ?
• edit the op-amp input pin so it's no longer of type "input", but something else — "passive", perhaps?
• Ignore the error?
• ... Something else ?

I thought I could change the "Project Options" | "Connection Matrix" entry for this error from "error" to "no report", but this particular error is not listed anywhere in the connection matrix.

-- DavidCary?