Verdin Carrier Board Design Guide
Preliminary
– Subject to Change
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Figure 4: PCIe reference clock buffer example
2.2.2.1
PCIe x1 Slot Connector Schematic Example
For a regular PCIe slot connector, no additional decoupling capacitors are permitted to be placed
on the carrier board in the RX, TX and reference clock lines. The decoupling capacitors are located
on the module and the PCIe card.
Figure 5: PCIe x1 Slot Connector Block Diagram
The Verdin module standard features a dedicated PCIe reset. This reset (PCIE_1_RESET#) should be
used to guarantee the power ramp up timing requirements of PCI Express. Since the PCIe slot
connector has a 3.3V logic level and the PCIE_1_RESET# output of the module is only 1.8V, a level
shifter is required. Please note that the Verdin module standard does not support PCIe hot-plug
functionality.
The PCIe x1 slot connector has two card present signals (PRSNT1#, pin A1 and PRSNT2#, pin B18)
which are shorted to ground by the card (if it is inserted). Since the Verdin standard does not
feature the PCIe hot-plug feature, these pins can be left unconnected or connected to any free
module GPIOs if the presence detection of the card needs to be emulated.
The wake output of the PCIe slot (WAKE#, pin B11) can be connected to the general wake input of
the Verdin module (CTRL_WAKE1_MICO#). Wake-up-capable PCIe cards such as Ethernet cards
can use this signal to wake up the module from the suspend state. The WAKE# signal of the PCIe
card 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 JTAG interface on the PCIe slot can be left unconnected. This interface is only used for
debugging purposes. No termination on the carrier board is needed.
PCIE1_CLK_N
PCIE1_CLK_P
PCIE1_CLK_N
PCIE1_CLK_P
PCIE1[0..1]
PCIE1A_CLK_N
PCIE1A_CLK_P
PCIE1B_CLK_N
PCIE1B_CLK_P
PCIE1C_CLK_N
PCIE1C_CLK_P
PCIE1A-C_CLK[0..5]
PCIE1A-C_CLK[0..5]
PCIE1_SDA
PCIE1_SCL
100nF
C2
100nF
C3
100nF
C4
100nF
C5
R1 33R
R3
33R
R5 33R
R6
33R
R7 33R
R8
33R
R10
R11
R12
R13
R14
R15
GND
1%
R16
475R
GND
GND
R9
1K
120R@100MHz
3A
L1
+V3.3_PCIE_CLK_BUF
+V3.3
+V3.3_PCIE_CLK_BUF
C1
2.2uF
GND
100nF
C6
120R@100MHz
3A
L2
+V3.3_PCIE_CLK_BUF
+V3.3_PCIE_CLK_BUF_A
+V3.3_PCIE_CLK_BUF_A
GND
+V3.3_PCIE_CLK_BUF
GND
+V3.3_PCIE_CLK_BUF
SRC_IN
2
SRC_IN#
3
OE_INV
25
DIF_1
6
SRC_STOP
16
BYPASS#/PLL
12
HIGH_BW
17
PD
13
SCLK
13
SDATA
14
OE6#
21
OE1#
8
DIF_1#
7
DIF_2
9
DIF_2#
10
DIF_5
20
DIF_5#
19
DIF_6
23
DIF_6#
22
IREF
26
VDD1
1
VDD2
5
VDD3
11
VDD4
18
VDD5
24
GND
4
ICS9DB401CGLF
GNDA
27
VDDA
28
IC1
6X
49.9R
PCIE_1_CLK_N
226
PCIE_1_CLK_P
228
PCIE_1_L0_RX_N
232
PCIE_1_L0_RX_P
234
PCIE_1_L0_TX_N
238
PCIE_1_L0_TX_P
240
PCIE_1_RESET#
244
X1V
2309409-2
R20 1K
R21 1K
+V3.3_PCIE_CLK_BUF
PCIe
Device
PCIe
Host
P
CI
e
Sl
o
t
C
o
nn
ec
to
r
M
o
du
le
C
o
nn
ec
to
r
Verdin Module
Carrier Board
PCIe Card
TX
RX
RX
TX
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
2x 100nF
2x 100nF
PET0+
PET0-
PER0+
PER0-