UMTS/HSPA Module Series
WCDMA UGxx Audio Design Note
WCDMA_UGxx_Audio_Design_Note Confidential / Released 16 / 56
3.6. Earphone Interface Design
The following figure shows the single-ended application for earphone design.
1
2
4
3
SPKP_PCM
MICN_PCM
MICP_PCM
22uF
Close to Socket
Differential layout
4.7uF
33pF
10pF
33pF
10pF
Earphone
32
Ω
0R
0R
Figure 8: Earphone Design
3.7. Speaker Amplifier Design
If the 8
Ω speaker is applied, it is recommended to add an audio amplifier.
Close to Speaker
SPKP_PCM
SPKN_PCM
10pF
10pF
10pF
33pF
33pF
33pF
Ri
Ri
Amplifier circuit
8
Ω
Figure 9: Speaker Amplifier Design
Quectel
Confidential