Ublox EVK-JODY-W2, User Manual

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EVK-JODY-W2 - User guide
UBX-19027118 - R06 Contents Page 10 of 25
C1 - Public
2. Connect the evaluation board to the host system by inserting the adapter card into an SDIO
connector on the host system.
⚠
Be careful when inserting the SDIO adapter into the SDIO slot of a laptop. Built-in readers can be
poorly designed and damage more easily than those on more compact development platforms.
2.4 Host interface for Wi-Fi (3.3 V HS)
By default, EVK-JODY-W2 operates with host interface voltage of 1.8 V. For the designs with host
interface voltage 3.3 V, a level shifter is needed to convert the voltage level of the SDIO signals. Only
SDIO High Speed (HS) mode is supported when using a 3.3 V interface voltage.
Figure 3 shows how the level shifter and EVK are connected. See also the level shifter integration
application note [3] .
Figure 3: EVK connection to level shifter
⚠
Level shifters are voltage sensitive. To avoid damaging the level shifter IC, connect the level shifter
so that host is in the same direction of the micro-SD adapter, as shown in
Figure 4 .
Figure 4: Level shifter direction
⚠
The level shifter is designed to connect with a host platform through the ZIF cable connector only.
It cannot work if connected directly to an SD card slot or adapter through the micro-SD extension
of the level shifter board. For the level shifter to work, position the resistors on the SDIO lines from
a horizontal to vertical orientation, as shown in the
Figure 5 .
Always connect this end to the host
platform through ZIF cables only .
Interface voltage: 3.3 V
Always connect to the
EVK-JODY-W2.
Interface voltage: 1.8 V