Verdin Carrier Board Design Guide
Preliminary
– Subject to Change
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Figure 7: Mini PCIe Card Block Diagram
The Verdin module standard features a dedicated PCIe reset. This reset (PCIE_1_RESET#) should be
used in order to guarantee the power ramp up timing requirements of PCI Express. Since the Mini
PCIe card has a 3.3V logic level for the reset input (PERST#, pin 22) and the PCIE_1_RESET# output
of the module is only 1.8V, a level shifter is required. Please note that the in the Verdin module
standard does not support PCIe hot-plug functionality.
The clock request output of the card (CLKREQ#, Pin 7) can be left unconnected. It might also be
connected to a free GPIO on the Verdin module. In this case, the clock request functionality needs
to be implemented in software.
The wake output of the Mini PCIe Card (WAKE#, pin 1) can be connected to the generic wake
input of the Verdin module (CTRL_WAKE1_MICO#). Wake-up-capable Mini PCIe Cards such as
Ethernet cards can use this signal to wake up the module from the suspend state. The WAKE#
signal of the Mini PCIe Cards slot is an open drain type. Therefore, no level shifter is required if the
signal is pulled up to 1.8V on the carrier board, and not to 3.3V.
The R-UIM interface of the Mini PCIe Card (UIM, pin 8, 10, 12, 14 and 16) are only needed for
mobile broadband modem cards such as 3G and 4G cards. If the card interface needs to support
such modems, an additional SIM card holder needs to be attached to this interface.
The Mini PCIe Card pin-out features an SMB interface for additional power management control.
As the SMB and I2C buses are compatible from a hardware perspective, it is recommended that
the general purpose I2C_1 interface on the Verdin module is used if the SMB interface is needed.
Most Mini PCIe Card do not make use of the SMB interface though. Therefore, these pins can be
left unconnected for most applications. Please note that the SMB interface has a logic level of 3.3V
while the I2C_1 has 1.8V. Therefore, a bidirectional level shifter is required.
PCIe
Device
PCIe
Host
Verdin Module
Carrier Board
PCIe Mini Card
TX
RX
RX
TX
PET0+
PET0-
PER0+
PER0-
2x 100nF
2x 100nF
USB_x_D_P
USB_x_D_N
USB_x_D_P
USB_x_D_N
USB_D+
USB_D-
P
CI
e
M
ini
C
ar
d
C
o
nn
ec
to
r
M
o
du
le
C
o
nn
ec
to
r
USB
Device
USB
Host
PCIE_1_L0_TX_P
PCIE_1_L0_TX_N
PCIE_1_L0_RX_P
PCIE_1_L0_RX_N
PCIE_1_L0_TX_P
PCIE_1_L0_TX_N
PCIE_1_L0_RX_P
PCIE_1_L0_RX_N
