A 200 Ω tuning resistor is connected to
the HHSx_RTUNE pin of each USB port.
Refer to “Typical Connection” in chapter “USB 2.0 PHY” of the SAMA7G5 Series data
sheet.
The TST pin is grounded.
If the design does not need JTAG boundary scan, tie the JTAGSEL pin to GND or leave it
floating.
A tuning resistor is connected to the
QSPI0_CAL and SDMMCx_CAL pins of each interface. Use a 20 kΩ resistor for 1.8V
QSPI/SDMMC memories or a 16.9 kΩ resistor for 3.3V memories. If the memory device
operates in both 1.8V and 3.3V modes, use a 20 kΩ resistor.
A 4.02 kΩ tuning resistor is connected to the MIPI_REXT pin.
All resistors connected to calibration inputs should have a tolerance of ±1% or
better.
A 32.768 kHz crystal oscillator is
placed between XIN32 and XOUT32.
Refer to “32.768 kHz Crystal Oscillator” in chapter “Electrical Characteristics”
of the SAMA7G5 Series data sheet.
A high-frequency clock source is
provided either through a crystal oscillator placed between XIN and XOUT or through an
external clock generator.
Refer to “Main Crystal Oscillator” in chapter “Electrical Characteristics” of the
SAMA7G5 Series data sheet if a crystal oscillator is used as main clock
source.
If the clock generator option is chosen, it is recommended to ground XOUT to improve
stability.
Clock sources should be chosen with
great care. In chapter “Electrical Characteristics” of the SAMA7G5 Series data sheet:
Refer to “Crystal Oscillator Design Considerations” for a list of useful
parameters when choosing crystal oscillators.
Refer to the formulas in "32.768 kHz Crystal Oscillator" and "Main Crystal
Oscillator" to calculate the value of the external load capacitors of the crystal
oscillators.
The online versions of the documents are provided as a courtesy. Verify all content and data in the device’s PDF documentation found on the device product page.
