User's Manual

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HW Design Guidelines
The layout design of this circuit on the carrier board should comply with the USB 2.0
high-speed protocol.
Layout suggestion:
Differential impedance: 90 Ω
Space to other signals should be at least 20 mils
Intra-lane length difference should be less than 150 mils
Maximum length for each trace:150 mm
Signals lengths on modules are tuned as below:
Function
Net
Length (mil)
USB
USB_Dp
545.54
USB_Dn
503.04
Input Low
0
0.8
Output High
2.8
3.3
3.6
Output Low
0.3
USB data positive (high-speed)
Input High
0.3
0.44
Input Low
0
0.01
Output High
0.36
0.38
0.44
Output Low
0
0.01
D–
USB data negative (low-/full-speed)
Input High
2
3.3
3.6
Input Low
0
0.8
Output High
2.8
3.3
3.6
Output Low
0.3
USB data negative (high-speed)
Input High
0.3
0.44
Input Low
0
0.01
Output High
0.36
0.38
0.44
Output Low
0
0.01