Analog Audio Interfaces - Quectel EC200U Series Hardware Design

PCM_DOUT 25
PCM_SYNC 26
PCM_CLK 27
The following figure shows the reference design of PCM and I2C interface with external Codec chip:
Figure 22: Reference Circuit of I2C and PCM Application with External Codec Chip
NOTE
It is recommended to reserve an RC (R = 22 Ω, C = 22 pF) circuit on the PCM traces, especially for
PCM_CLK.

3.14. Analog Audio Interfaces

The module provides one analog audio input channel and one analog audio output channel. The pin
definition is shown in the table below.
Table 21: Pin Definition of Analog Audio Interfaces
Interface
AOUT
EC200U_Series_Hardware_Design
DO PCM data output
DI PCM data frame sync
DI PCM clock
External 26MHz Crystal
MAIN_DCD
PCM_CLK
PCM_SYNC
PCM_DOUT
PCM_DIN
I2C_SCL
I2C_SDA
Module
1.8 V
Pin Name Pin No.
LOUDSPK_P 73
1.8 V power domain.
If unused, keep it open.
1.8 V power domain.
If unused, keep it open. The PCM
function only supports slave mode.
NM 0R
MCLK
0R
BCLK
LRCK
DAC
ADC
SCL
SDA
I/O
AO
LTE Standard Module Series
MICBIAS
INP
INN
LOUTP
LOUTN
Codec
Description
Loudspeaker differential
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