Quectel EG91 Series Hardware Design page 51

EG91 series module supports 16-bit linear data format. The following figures show the primary mode's
timing relationship with 8 kHz PCM_SYNC and 2048 kHz PCM_CLK, as well as the auxiliary mode's
timing relationship with 8 kHz PCM_SYNC and 256 kHz PCM_CLK.
P CM _CLK
P CM _S YNC
P CM _DOUT
P CM _DIN
P CM _CLK
P CM _S YNC
P CM _DOUT
P CM _DIN
The following table shows the pin definition of PCM and I2C interfaces which can be applied on audio
codec design.
EG91_Series_Hardware_Design
125 μs
1 2
MS B LS B
MS B LS B
Figure 22: Primary Mode Timing
125 μs
1 2
MS B
MS B
Figure 23: Auxiliary Mode Timing
LTE Standard Module Series
25 5 2 56
MS B
MS B
31 32
LS B
LS B
50 / 105