Data Sheet

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11. The other layout guide Information
• Make sure every power traces have good return path (ground path).
• Connect the input pins of unused internal regulators to ground.
• Leave the output pins of unused internal regulators floating.
• High speed interface (i.e. UART/SDIO/HSIC) shall have equal electrical length. Keep them away from
noise sensitive blocks.
• Good power integrity of VDDIO will improve the signal integrity of digital interfaces.
• Good return path and well shielded signal can reduce crosstalk, EMI emission and improve signal
integrity.
• RF IO is around 50 ohms, reserve Pi or T matching network to have better signal transition from port to
port.
• Smooth RF trace help to reduce insertion loss. Do not use 90 degrees turn (use two 45 degrees turns or
one miter bend instead).
• Well arranged ground plane near antenna and antenna itself will help to reduce near field coupling
between other RF sources (e.g. GSM/CDMA … antennas).
• Discuss with AzureWave Engineer after you finish schematic and layout job.