User's Manual

10.1. Electrical Characteristics
TIP: Being the microphone circuitry the more noise sensitive, its design and layout must be
done with particular care. Both microphone paths are balanced and the OEM circuitry must
be balanced designed to reduce the common mode noise typically generated on the ground
plane. However the customer can use the unbalanced circuitry for particular application.
10.1.1. Input Lines
“MIC 1” differential microphone path
Line Coupling
AC*
Line Type
Balanced
Coupling capacitor
≥ 100nF
Differential input resistance
50kΩ
Differential input voltage
≤ 1,03V
pp
@ MicG=0dB
(*) WARNING : AC means that the signals from the microphone have to be connected to
input lines of the module through capacitors which value has to be ≥ 100nF. Not
respecting this constraint, the input stages will be damaged.
WARNING: when particular OEM application needs a Single Ended Input configuration, it is
forbidden connecting the unused input directly to Ground, but only through a capacitor which
value has to be ≥ 100nF..
Don’t forget that in Single Ended configuration the useful input signal will be halved.