Reproduction forbidden without Fibocom Wireless Inc. written authorization - All Rights Reserved.
FIBOCOM SU806 Series Hardware Guide
Page 54 of 91
Pin Name
Pin
Number
I/O
Description
Note
MIC2_P
6
AI
Headset mic input
-
MIC1_M
5
AI
Main mic difference input-
-
MIC1_P
4
AI
Main mic difference input+
-
MIC3_P
220
AI
Sub-mic input
-
Design notice:
1) SU806 series module has MIC bias circuit internally, and no external addition is required.
2) The SPK is configured as class D amplifier output, cannot connect with amplifier externally, it is
recommended to connect
8Ω speakers. Note that the route width must meet the power rating
requirements; If an external audio amplifier is required, please use the output of headphone as the
input of external audio amplifier.
3) The reference ground of the headphone has already grounded in the module. The external circuit is
recommended not to be grounded and resistor can be reserved.
4) It is recommended to use earpiece with 32
Ω impendence.
5) Reduce noise and improve audio quality, the following approaches are recommended.
Keep audio PCB routing away from the antenna and high-frequency digital signal.
Reserve LC filter circuit in audio circuit to reduce EMI.
Audio routing needs to be masked.