Toradex Apalis Series - 2.3 SATA

Apalis Carrier Board Design Guide
Toradex AG l Altsagenstrasse 5 l 6048 Horw l Switzerland l +41 41 500 48 00 l www.toradex.com l info@toradex.com
Page | 19
2.2.3 Unused PCIe Signals Termination
Apalis
Pin
Apalis
Signal Name
Recommended Termination
55
PCIE1_CLK+
Leave NC if not used
53
PCIE1_CLK-
Leave NC if not used
49
PCIE1_TX+
Leave NC if not used
47
PCIE1_TX-
Leave NC if not used
43
PCIE1_RX+
Preferable connect to GND if not used or leave NC
41
PCIE1_RX-
Preferable connect to GND if not used or leave NC
37
WAKE1_MICO
Add pull-up resistor or disable the wake function in software
26
RESET_MOCI#
Leave NC if not used
209
I2C1_SDA
Add pull-up resistor or disable the I
2
C function in software
211
I2C1_SCL
Add pull-up resistor or disable the I
2
C function in software
Table 4: Unused PCIe Signals Termination
2.3 SATA
The Apalis module form factor features one SATA interface as standard interface. Depending on
the module, there are maybe additional interfaces type-specific SATA interfaces available.
2.3.1 SATA Signals
Apalis
Pin
Apalis
Signal Name
I/O
Type
Power
Rail
Description
33
SATA1_TX+
O
SATA
SATA transmit data positive
31
SATA1_TX-
O
SATA
SATA transmit data negative
25
SATA1_RX+
I
SATA
SATA receive data positive
27
SATA1_RX-
I
SATA
SATA receive data negative
35
SATA1_ACT#
O
OD
3.3V
Activity indication LED output, active low
Table 5: SATA Signals
The SATA interface does not support polarity inversion. This means the positive and negative signal
pins cannot be swapped for layout simplification.
2.3.2 Reference Schematics
Every SATA interface consists of a pair of transmitting (TX) and receiving (RX) traces. Unfortunately,
the names RX and TX can be confusing, as at the end, the transmitter of the host needs to be
connected to the receiver of the device and vice versa. Normally, the signals are named after the
host until they reach the pins of the SATA device. Therefore, the transmitting pins of the Apalis
modules should be called TX on the carrier board while the receiving input pins of the Apalis
module should be called RX.
2.3.2.1 SATA Connector Schematic Example
The AC coupling capacitors for the RX and TX lines are placed on the Apalis module. Therefore, no
additional serial capacitors are needed nor permitted on the carrier board.