Hardware Development Guide of Module Product
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34
MF206A
3.7
USB2.0 Interface
3.7.1
Description of PINs
MF206A has the high-speed USB2.0 interface, which supports both the full-speed mode and the high-speed
mode. The main processor (AP) is connected with the module via the USB interface to transmit data.
3.7.2
Electric Feature
The USB interface complies with the USB2.0 specifications and the electric features. USB_DP, USB_DM are
wired strictly according to the differential mode, and the length difference between the two cables should be
restricted within 1mm.
NOTE:
NOTE: If the users of module need the wakeup and sleep function, and your AP side connects with the
module through USB interface, the AP side needs to support USB suspend and resume to realize this
function.
The differential impedance should be controlled within 90ohm.
It is recommended to connect to a high-speed common-mode echo filter on the USB differential signal wire. If
the cable is exposed to the external environment, it is suggested to add an ESD protection device. The power
capacity of the ESD protection device should be kept within 1.5pF.
3.7.3
Application of USB Interface
The USB bus is mainly used in data transmission, software upgrading and modular program detection. Figure
3–4 shows a reference circuit design.