Have a question regarding the ADMP401 microphone.
The sound-port (drill-hole) in the PCB.
The datasheet says: A minimum diameter of 0.5 mm is recommended.
We did a board now with 0.5mm hole.When testing the mic it's very "directional", that is talking directly against the port = loud signal, but just a slight angle away results in way less sensitive input signal.
Is there any reason we should look at doing the opening bigger to prevent this?
I'm also thinking 0.5 makes it very sensitive to minimal misalignments during assembly.
Would it be a risk of doing the sound-port 1mm?
Also, in the case of enlarging the hole, should you consider a "cloth" to cover the opening to prevent wind/puff-noise when talking straight into the mic?