Figure 4: Block diagram of the EVK-R4 for SARA-R4 modules
The EVK-R4 is formed by three boards:
•The lower one, called EVB-WL3, contains the power supply and other peripherals for the SARA-R4
series cellular module (SIM card holder, Reset button and Power-on button).
•The cellular adapter board, called ADP-R4, contains the SARA-R4 cellular module, the cellular
antenna connector and the USB connector for the cellular module.
•The GNSS adapter board, called ADP-GNSS, contains the u-blox GNSS module, the GNSS antenna
connector and the USB connector for the GNSS module.
The boards are connected by means of male header board-to-board connectors provided on the
bottom of the adapter boards and their corresponding female connectors provided on top of the lower
board.
The USB interface of the cellular module is available on the native USB connector on the cellular
adapter board, while the other peripherals are available on the dual-in-line male board-to-board
connectors provided on the top layer of the cellular adapter board, which are pin-to-pin compatible to
the connectors on the bottom layer of the adapter board.
The lower board (EVB-WL3) is designed to also be used with other u-blox cellular adapter boards. It
contains additional switches, jumpers, connectors, LEDs and parts that are only partially described in
Figure 1, Figure 2, Figure 3, and in this document, because they are intended for use only with other
u-blox cellular modules. It is recommended to leave any additional connector unconnected, and to
leave any additional switch in its default configuration.
