22
/
50
PCM_CLK
PCM_SYNC
PCM_DOUT
MSB
LSB
PCM_DIN
125us
MSB
1
2
16
15
LSB
Figure 7: Timing in Auxiliary Mode
Clock and mode can be configured by AT command, and the default configuration is master mode using
short frame synchronization data format with 2048kHz PCM_CLK and 8kHz PCM_SYNC. In addition, the
module’s firmware has integrated the configuration on some PCM codec’s application with I2C interface.
The following figure shows a reference design of PCM interface with an external codec IC.
PCM_DIN
PCM_DOUT
PCM_SYNC
PCM_CLK
I2C_SCL
I2C_SDA
Codec
Module
1.8V
2
.2
K
2
.2
K
BCLK
FS
DACIN
ADCOUT
SCLK
SDIN
B
IA
S
MIC_BIAS
MIC+
MIC-
SPKOUT-
Figure 8: Reference Circuit of PCM Application with Audio Codec
3.7.
Control Signals
The following table shows the pin definition of control signals.
