Usb_Boot Interface; Gpio Interfaces - Quectel QuecOpen AG521R-NA Hardware Design

ADC Sample Rate
NOTES
1. The input voltage for each ADC interface must not exceed its corresponding voltage range.
2. It is prohibited to supply any voltage to ADC pins when VBAT is removed.
3. It is recommended to use resistor divider circuit for ADC application.

3.18. USB_BOOT Interface

The module provides a USB_BOOT pin. Pulling up the USB_BOOT to VDD_EXT before powering on the module
will force the module into emergency download mode when powered on. In emergency download mode, the
module supports firmware upgrade over USB 2.0 interface.
Table 26: Pin Definition of USB_BOOT Interface
Pin Name Pin No.
USB_BOOT 83
The following figure shows a reference circuit of USB_BOOT interface.

3.19. GPIO Interfaces

The module provides 8 GPIOs.
AG521R-NA_QuecOpen_Hardware_Design
I/O Description
Force the module into emergency
DI
download mode
Module
USB_BOOT
TVS
Figure 30: Reference Circuit of USB_BOOT Interface
AG521R-NA QuecOpen Hardware Design
4.8
VDD_EXT
Test point
10K
Close to module
Automotive Module Series
MHz
Comment
1.8 V power domain.
Active high.
If unused, keep it open.
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