H330SS LGA Module Hardware User Manual Page 32 of 38
5.7.2
Audio Description
The audio input and output channels are differential interfaces. And have prefect performance at RF Spurious
suppression. When connect to the handset, need external audio amplifier.
In PCB Layout, the differential lines need equal length, parallel,
5.7.2.1
Audio Channel 1
as short as possible, for a better performance,
the input and output need GND Isolation and the interface need to
add ESD protection.
Audio channel 1 interface use differential lines, it can be used for handling calls
Audio channel 1
：
MIC input characteristic:
Parameter
Test conditions
Minimum Value
Typical Value
Maximum Value
Unit
Bias voltage
No load
2.5
2.6
V
Gain
Programmable
，
steps gain:2dB
0
16
dB
Load resistance
2.2
Kohm
Audio channel 1
：
EAR output characteristic:
Parameter
Test conditions
Minimum Value
Typical Value
Maximum Value
Unit
Output voltage
No load
1.4
Vpp
Load resistance
32
ohm
DC Bias voltage
1
V
5.7.2.2
Audio Channel 2
Audio channel 2 interface use differential lines, Can be use as Hands-free.
Note: The downstream of Audio channel 2 cannot work until VSPK power supply is normal.
The VSPK can be straight connected to VBAT.
Audio channel 2: AUXI input characteristic:
Parameter
Test conditions
Minimum Value
Typical Value
Maximum Value
Unit
Bias voltage
No load
2.5
2.6
V
Gain
Programmable
，
steps gain:2dB
0
32
dB
Load resistance
2.2
Kohm
