LTE Module Series
EC20 Mini PCIe Hardware Design
EC20_Mini_PCIe_Hardware_Design Confidential / Released 24 / 36
The following figure shows the reference design of PCM interface with external codec IC (such as
ALC5616).
PCM_DIN
PCM_DOUT
PCM_SYNC
PCM_CLK
I2C_SCL
I2C_SDA
Codec
Module
1.8V
4
.7
K
4
.7
K
BCLK
FS
DACIN
ADCOUT
SCLK
SDIN
B
IA
S
MIC_BIAS
MIC+
MIC-
SPKOUT-
Figure 10: Reference Circuit of PCM Application with Audio Codec
3.8. Control Signals
The following table shows the pin definition of control signals.
Table 10: Control Signal Pin Definition
Pin No.
Pin Name
I/O
Power Domain
Description
17
RI
DO
3.3V
URC ring indication, can be used to
wake up the host
31
DTR
DI
3.3V
Sleep mode control
20
W_DISABLE#
DI
3.3V
Disable wireless communications
Pull-up by default. Active low
22
PERST#
DI
3.3V
Functional reset to the card
Active low
42
LED_WWAN#
OC
—
Active-low LED signal for indicating
the state of the Module
Quectel
Confidential
