User's Manual

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L850-GL Hardware User Manual Page
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Figure 3-10 Reset Timing Control
Note:
RESET# is a sensitive signal, it’s recommended to add a filter capacitor close to the module. In
case of PCB layout, the RESET# signal lines should keep away from the RF interference and
protected by GND. Also, the RESET# signal lines shall neither near the PCB edge nor route on
the surface planes to avoid module from reset caused by ESD problems.
3.4 USB Interface
The L850 module supports USB2.0 which is compatible with USB High-Speed (480 Mbit/s) and USB
Full-Speed (12 Mbit/s). For the USB timing and electrical specification of L850 module, please refer
to“Universal Serial Bus Specification 2.0”.
USB interface just for debugging.
3.4.1 USB Interface Definition
Pin#
Pin Name
I/O
Reset Value
Description
Type
7
USB_D+
I/O
USB Data Plus
0.3---3V,
USB2.0
9
USB_D-
I/O
USB Data Minus
0.3---3V,
USB2.0
3.4.2 USB2.0 Interface Application
USB interface is used for debugging only, so it only needs to introduce the USB interface test in hardware
design.