LTE Standard Module Series
EG915U_Series_Hardware_Design 22 / 81
SPI_DIN
88
DI
SPI master mode input
V
IL
min = -0.3 V
V
IL
max = 0.6 V
V
IH
min = 1.26 V
V
IH
max = 2.0 V
SPI_DOUT
64
DO
SPI master mode output
V
OL
max = 0.45 V
V
OH
min = 1.35 V
ADC Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics Comment
ADC0
24
AI
General-purpose ADC
interface
Voltage range:
0.1 V to VBAT
If unused, keep it
open.
ADC1
2
AI
Analog Audio Interfaces
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
MIC_N
119
AI
Microphone analog input
(-)
MICBIAS
120
PO
Bias voltage output for
microphone
Vo = 2.2
–3.0 V
Vnom = 2.2 V
SPK_P
121
AO
Analog audio differential
output (+)
SPK_N
122
AO
Analog audio differential
output (-)
MIC_P
126
AI
Microphone analog input
(+)
USB_BOOT
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
USB_BOOT
75
DI
Control pin for module to
enter download mode
V
IL
min = -0.3 V
V
IL
max = 0.6 V
V
IH
min = 1.26 V
V
IH
max = 2.0 V
1.8 V power
domain.
Active high.
A circuit that
enables the
module to
enter the
download
mode must be
reserved.
PSM
Interface
*
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
