User guide

M33 EVB User Guide
Figure 7: Audio interface
Table 3: Pins of audio channel 1
Pin Signal I/O Description
1 MIC1N I Negative microphone input
2 SPK1N O Negative receiver output
3 SPK1P O Positive receiver output
4 MIC1P I Positive microphone input
Table 4: Pins of audio channel 2
Pin Signal I/O Description
1 AGND
2 AGND
AGND of audio circuits
3 SPK2P O Positive receiver output
4 MIC2P I Positive microphone input
3.3. SIM Card Interface
Figure 8: SIM card interface
Table 5: Pins of SIM card interface
Pin Signal I/O Description
1 SIM_GND GND, dedicated for SIM card
M33_EVB_UGD_V1.0 - 13 -
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