Quectel EC200U Series Hardware Design page 62

LTE Standard Module Series
MODULE
MODULE
S1
KEYOUT0
VDD_EXT
Test points
2 1
4.7K
USB_BOOT
USB_BOOT
3
GND
TVS
TVS TVS
Close to test points
Close to test points
Figure 28: Reference Circuit of USB_BOOT Interface
NOTE
Please make sure that VBAT is stable before PWRKEY is pulled down. It is recommended that the time
interval between powering up VBAT and pulling down PWRKEY is no less than 30 ms.
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