Quectel EG21-G Reference Design page 13

6
D
U0201
VDD
GND
TXD
RXD
CTS
RTS
DCD
DTR
C
USB_VBUS
USB_D+
USB_D-
USB_ID
GPIO_01
GPIO_02
GPIO_03
GPIO_04
GPIO_05
GPIO_06
GPIO_07
GPIO_08
GPIO_09
GPIO_10
GPIO_11
GPIO_12
GPIO_13
B
Notes:
1. U0201 represents customers's MCU. The power domain of GPIO interfaces on EG21-G modules is 1.8V. If the domain on U0201's GPIO interfaces is the same, then the level translation circuit can be omitted.
2. EG21-G can only work as a USB device and supports Full Speed and High Speed modes. To communicate with USB interface, MCU needs to support USB host or OTG function.
The USB_VBUS pins of MCU and EG21-G should be powered by a 5V power system for USB detection, and USB_VBUS_CTRL is used to turn on/off USB_VBUS power supply.
3. AP_READY is used to detect the MCU's sleep state. For more details, please refer to
4. WAKEUP_IN_EG21-G should be kept at low level before the module starts up successfully.
A
6
5
VDD_MCU
RXD [6]
[6]
TXD
CTS [6]
RTS [6]
RI [6]
RI
[6]
DCD
DTR [6]
[3,4,14]
USB_VBUS
[3]
USB_DP
[3]
USB_DM
VBAT_EN [5]
[4]
VBUS_CTRL
ON/OFF_MCU [4]
RESET_MCU [4]
[4]
W_DISABLE_MCU
SLEEP_STATUS [4]
[5]
CODEC_POWER_EN
[4]
WAKEUP_IN_MCU
[13]
SD_PWR_EN
5
4 3
MCU Interface
It is used to turn on or off the module.
Q0201
[4] ON/OFF_MCU
DTC043ZEBTL
It is used to wake up the module.
Q0203
[4] WAKEUP_IN_MCU
DTC043ZEBTL
VDD_EXT VDD_EXT
C0204
R0202
R0201
4.7K
4.7K 1nF
Q0206
[3] AP_READY_EG21-G
2SC4617TLQ
Quectel_EG21-G_Hardware_Design.
3
4
2
It is used to reset the module.
[3,14]
PWRKEY
Q0202
[4] RESET_MCU
C0201
DTC043ZEBTL
10nF
It is used to let the module enter airplane mode.
[3]
WAKEUP_IN_EG21-G
Q0204
C0202
[4] W_DISABLE_MCU
10nF DTC043ZEBTL
5V power source from main board.
[5,14] DC_5V
[4]
SLEEP_STATUS
R0204
10K
[4] VBUS_CTRL
Quectel Wireless Solutions
DRAWN BY
Lorry XU
CHECKED BY
Woody WU
2
1
[3]
RESET_N
C
[3]
W_DISABLE_EG21-G
C0203
10nF
Q0205
[3,4,14]
USB_VBUS
S D
SI2333CDS-T1
Q0207
DTC043ZEBTL
PROJECT TITLE
EG21-G Reference Design
VER
SIZE
A2 1.0
SHEET 4 OF 14 DATE 2019/12/5
1
D
B
A