M20 Hardware Design
MIC2P
MIC2N
I
Audio input channel 2.
Positive and negative voice
input.
Microphone
bias voltage
supplied
internally. If
unused, keep
these pins
open.
SPK1P
SPK1N
O Audio output channel 1.
Positive and negative voice
output.
If unused
keep these
pins open.
SPK2P
O Audio output channel 2.
Auxiliary voice output.
If unused
keep this pin
open.
AGND
AGND is a separate ground
connection for external audio
circuit.
If
unused
keep this pin
open.
General purpose input/output
PIN NAME
I/O DESCRIPTION
DC CHARACTERISTICS COMMENT
NETLIGHT O Network
status indication
VILmin=0V
VILmax=0.67V
VIHmin=1.7V
VIHmax= 0.3
VOLmin=GND
VOLmax=0.34V
VOHmin=2.0V
VOHmax= VDD_EXT
If unused
keep this
open.
DAI interface
PIN NAME
I/O DESCRIPTION
DC CHARACTERISTICS COMMENT
RXDDAI
I
Receive digital audio data
TFSDAI O
Frame
synchronization
SCLK O
Serial
bit
clock
TXDDAI
O
Transmit digital audio data
VILmin=0V
VILmax=0.67V
VIHmin=1.7V
VIHmax= 0.3
VOLmin=GND
VOLmax=0.34V
VOHmin=2.0V
VOHmax= VDD_EXT
If unused
keep these
pins open.
Serial Port 0
PIN NAME
I/O DESCRIPTION
DC CHARACTERISTICS COMMENT
DTR0 I
Data
terminal
ready
RXD0 I
Receiving
data
TXD0 O
Transmitting
data
RTS0 I
Request
to
send
CTS0 O
Clear
to
send
VILmin=0V
VILmax=0.67V
VIHmin=1.7V
VIHmax= 0.3
VOLmin=GND
If only use
TXD0 and
RXD0 to
communicate,
recommend to
M20_HD_V1.01
- 20 -
Quectel