Telit Wireless Solutions ME910G1, Руководство по конструкции

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ME910G1 Hardware Design Guide
1VV0301593 Rev.12
Page 45 of 93 2021-09-24
Not Subject to NDA
The USB_DPLUS and USB_DMINUS signals have a clock rate of 480 MHz, so the signal
traces should be carefully routed. Trace lengths, number of vias and capacitive loading
should be minimized. The characteristic impedance value should be as close as possible
to 90 Ohms differential.
ESD protection can be added to USB D+/D- lines in case of external connector for cable
connection. Proper components for USB 2.0 must be used.
SPI
The ME910G1 Module is provided by a standard 3-wire master SPI int chip select
control.
The following table lists the available signals:
PAD Signal I/O Function Type NOTE
D15 SPI_MOSI O SPI MOSI CMOS 1.8V
Shared with
TX_AUX
E15 SPI_MISO I SPI MISO CMOS 1.8V
Shared with
RX_AUX
F15 SPI_CLK O SPI Clock CMOS 1.8V
H14 SPI_CS O SPI Chip Select CMOS 1.8V
Table 21: Available Signals
Note: Due to the shared functions, SPI port and TX_AUX/RX_AUX port
cannot be used simultanously.
Refer to ME910G1 series AT command reference guide for port
configuration.
SPI Connections
Figure 13: SPI Connections
SPI_CS
SPI_MISO
SPI_MOSI
SPI_CLK
E15
D15
F15 ME910G1
Application
Processor
H14
SPI_CS