Quectel SC20 Series - Page 29

Smart Module Series
SC20_Series_Hardware_Design 28 / 133
UART1_RX 35 DI UART1 receive
V
IL
max = 0.63 V
V
IH
min = 1.17 V
If unused, keep
these pins open.
UART1_CTS 36 DI
DTE clear to send
signal from DCE
V
IL
max = 0.63 V
V
IH
min = 1.17 V
Connect to DTE’S
CTS;
1.8 V power
domain.
If unused, keep
these pins open.
UART1_RTS 37 DO
DTE request to
send signal to
DCE
V
OL
max = 0.45 V
V
OH
min = 1.35 V
Connect to DTE’S
RTS;
1.8 V power
domain.
If unused, keep
these pins open.
UART2_RX 93 DI
UART2 receive;
Debug port by
default
V
IL
max = 0.63 V
V
IH
min = 1.17 V
1.8 V power
domain.
If unused, keep
these pins open.
UART2_TX 94 DO
UART2 transmit;
Debug port by
default
V
OL
max = 0.45 V
V
OH
min = 1.35 V
SD Card Interface
Pin Name
Pin
No.
I/O Description DC Characteristics
Comment
SD_LDO11 38 PO
SD card power
supply
Vnom = 2.95 V
I
O
max = 600 mA
SD_LDO12 32 PO
1.8/2.95 V output
power for SD card
pull-up circuits
Vnom = 1.8/2.95 V
I
O
max = 50 mA
SD_CLK 39 DO SD card clock
1.8 V SD card:
V
OL
max = 0.45 V
V
OH
min = 1.4 V
2.95 V SD card:
V
OL
max = 0.37 V
V
OH
min = 2.2 V
Control
characteristic
impedance as 50
Ω.
SD_CMD 40 DIO
SD card
command
1.8 V SD card:
V
IL
max = 0.58 V
V
IH
min = 1.27 V
V
OL
max = 0.45 V
V
OH
min = 1.4 V
SD_DATA0 41 DIO SDIO data bit 0
SD_DATA1 42 DIO SDIO data bit 1