Unex OBU-352 Series User manual

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Document Number
Unex-QSG-21-001
Revision
0.9
Authors
Nidor Huang
Quick Start Guide
for
OBU-352 Family
Product Variants
Model
Description
OBU-352
V2X On-Board Unit, 0A1
OBU-352ED
DSRC-V2X On-Board Unit, V2Xcast® - Europe ETSI ITS-G5 stack, 0A1
OBU-352UC
C-V2X On-Board Unit, V2Xcast® - US C-V2X stack, 0A1
OBU-352UD
DSRC-V2X On-Board Unit, V2Xcast® - US DSRC/WAVE stack, 0A1
EVK-352
V2X Starter Kit, 0A1
EVK-352ED
DSRC-V2X Starter Kit, V2Xcast® - Europe ETSI ITS-G5 stack, 0A1
EVK-352UC
C-V2X Starter Kit, V2Xcast® - US C-V2X stack, 0A1
EVK-352UD
DSRC-V2X Starter Kit, V2Xcast® - US DSRC/WAVE stack, 0A1
Reviewers
Department
Name
Acceptance Date
Note
PD
Nidor Huang
2023/07/10
RD
P.C Kang
2023/07/10
Modification History
Revision
Date
Originator
Comment
0.1
2021/08/23
Nidor Huang
Creating document
0.2
2021/10/13
Nidor Huang
Adding product variants
Adding product characteristics
Adding dimensions and weight
Adding EVK package content
0.3
2022/04/15
Nidor Huang
Adding GNSS antenna detection mechanism
0.4
2022/07/13
Nidor Huang
Adding tamper backup power description
0.5
2022/12/30
Nidor Huang
Updating product variants to 352 series
Updating functional block diagram

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Revision
Date
Originator
Comment
Updating product photos
0.6
2023/03/03
Nidor Huang
Updating Unex BSP interface settings
Updating product photos
Adding V2X antenna detection function
Updating maximum supply voltage
0.7
2023/03/08
Nidor Huang
Updating Unex logo
Adding GNSS reset in Unex BSP interface settings
0.8
2023/05/10
Nidor Huang
Changing Ethernet over USB protocol to RNDIS
0.9
2023/07/10
Nidor Huang
Updating functional block diagram
Updating SAR_ADC file path
Removing EC series from product variants

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TABLE OF CONTENTS
1. Objective...................................................................................................6
2. Reference .................................................................................................6
3. Limited Warranty Policy ............................................................................6
4. Safety Guidelines......................................................................................7
5. Product Appearance .................................................................................7
6. Functional Block Diagram.........................................................................9
7. Electrical Characteristics ........................................................................10
7.1. Absolute Maximum Ratings ................................................................................ 10
7.2. Recommended Operating Conditions................................................................. 10
7.3. Power Consumption............................................................................................ 12
8. I/O Interfaces ..........................................................................................12
8.1. OBU-352 ............................................................................................................. 12
8.1.1. External Interfaces ................................................................................ 12
8.1.2. Internal Interfaces ................................................................................. 18
8.2. I/O Conversion Board (EVK-352 Series Only) .................................................... 24
8.2.1. Console................................................................................................. 24
8.2.2. Ext GNSS.............................................................................................. 25
8.2.3. CAN0 .................................................................................................... 25
8.2.4. CAN1 .................................................................................................... 26
8.2.5. USB1..................................................................................................... 27
8.2.6. GPIO ..................................................................................................... 27
8.2.7. DC Power Jack ..................................................................................... 28
8.2.8. Reset Button ......................................................................................... 28
9. Dimensions and Weight ..........................................................................29
10. Software Settings....................................................................................30
LIST OF FIGURES
Figure 1: OBU-352 series package content .............................................................................. 8
Figure 2: EVK-352 series package content............................................................................... 8
Figure 3: OBU-352 series complete assembly appearance...................................................... 9
Figure 4: Functional block diagram ........................................................................................... 9
Figure 5: LED........................................................................................................................... 12
Figure 6: USB0 (CN2) ............................................................................................................. 13
Figure 7: Ethernet port............................................................................................................. 14
Figure 8: I/O port (J8) .............................................................................................................. 14
Figure 9: I/O port cable connector ........................................................................................... 15

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Figure 10: V2X antenna ports.................................................................................................. 16
Figure 11: GNSS antenna port ................................................................................................ 16
Figure 12: Mini PCIe Port (J6) ................................................................................................. 18
Figure 13: SIM slot (J7) ........................................................................................................... 20
Figure 14: Tamper input (J5) ................................................................................................... 21
Figure 15: SAR ADC input (J4)................................................................................................ 22
Figure 16: DIP switches. SW3 (Left), SW2 (Right).................................................................. 23
Figure 17: EX-46 (Left), EX-47 (Right) .................................................................................... 24
Figure 18: Console port (CN4) ................................................................................................ 24
Figure 19: Ext GNSS port (CN6) ............................................................................................. 25
Figure 20: CAN0 port (CN5) .................................................................................................... 25
Figure 21: CAN0 terminator jumpers (JP1/JP2)...................................................................... 26
Figure 22: CAN1 port (CN7) .................................................................................................... 26
Figure 23: CAN1 terminator jumpers (JP3/JP4)...................................................................... 27
Figure 24: USB1 port (CN2) .................................................................................................... 27
Figure 25: GPIO headers (J1) ................................................................................................. 27
Figure 26: DC power jack ........................................................................................................ 28
Figure 27: Reset button ........................................................................................................... 28
Figure 28: Mechanical dimensions - TOP ............................................................................... 29
Figure 29: Mechanical dimensions - FRONT .......................................................................... 29
LIST OF TABLES
Table 1. Absolute maximum ratings......................................................................................... 10
Table 2. Recommended operating conditions ......................................................................... 10
Table 3: Power consumption ................................................................................................... 12
Table 4: LED function .............................................................................................................. 13
Table 5: USB0 (CN2) pinout .................................................................................................... 13
Table 6: Ethernet LED function................................................................................................ 14
Table 7: I/O port pin map (J8) .................................................................................................. 15
Table 8: I/O port pinout (J8) ..................................................................................................... 15
Table 9: V2X antenna status.................................................................................................... 16
Table 10: GNSS antenna status .............................................................................................. 17
Table 11: Mini PCIe pinout (J6, Row 0) ................................................................................... 18
Table 12: Mini PCIe pinout (J6, Row 1) ................................................................................... 19
Table 13: Tamper functions (J5) .............................................................................................. 21
Table 14: SAR ADC functions.................................................................................................. 22
Table 15: SAR ADC performance ............................................................................................ 23
Table 16: SW2 and SW3 functions .......................................................................................... 23

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Table 17: Console pinout (CN4) .............................................................................................. 24
Table 18: Ext GNSS pinout (CN6) ........................................................................................... 25
Table 19: CAN0 pinout (CN5) .................................................................................................. 25
Table 20: CAN1 pinout (CN7) .................................................................................................. 26
Table 21: USB1 pinout (CN2) .................................................................................................. 27
Table 22: GPIO pinout (J1) ...................................................................................................... 27
Table 23: Dimensions and weight............................................................................................ 29
Table 24: Unex BSP interface settings .................................................................................... 30

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1. Objective
The purpose of this document is to provide necessary information to help setup and
installation of OBU-352 series product. To provide for safe installation and operation of the
equipment, read the safety guidelines at the beginning of this manual and follow the
procedures outlined in the following chapters before connecting power to OBU-352. Keep
this operating manual handy and distribute to all users, technicians and maintenance
personnel for reference.
2. Reference
•Unex OBU-352 datasheet
•Unex EVK-352 datasheet
3. Limited Warranty Policy
Unex Technology Corporation selling the product warrants that commencing from the
date of shipment to customer and continuing for a period of twelve (12) months. This limited
warranty extends only to the original customer of the product. Customer's sole and
exclusive remedy and the entire liability of Unex under this limited warranty will be, at
Unex's option, return for repair to Unex's repair center with freight and insurance prepaid
or shipment of a replacement within the warranty period or a refund of the purchase price
if the hardware is returned to Unex. Unex’s obligations hereunder are conditioned upon the
return of affected hardware in accordance with Unex's service center's then-current Return
Material Authorization (RMA) procedures.
This warranty does not cover:
•Products found to be defective after the warranty period has expired.
•Products subjected to misuse or abuse, whether by accident or other causes.
Such product conditions will be determined by Unex at its sole and unfettered
discretion.
•Products damaged due to a natural disaster, including but not limited to
lightning, flooding, earthquake, or fire.
•Software products.
•Products dismantled or opened by unauthorized persons. Please contact a
representative of Unex if you need advanced technical support.
•Products with an altered and/or damaged serial number.

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•Loss of data or software.
•Products that have been updated, reworked, or improperly tested by the
Customer, or by a third party at the request of the Customer.
•Customized and original design manufacturer (ODM) products. The warranty
terms for customized and ODM products should be defined in the contract
that governs the project.
4. Safety Guidelines
•Keep working area clean and dry while assembling/installing.
•When operating under extreme temperature conditions, environmental control
measures (e.g., heating, cooling) should be considered.
•It is suggested to connect the metal enclosure to a well-grounded metal structure
(i.e., vehicular chassis).
•Make sure every accessory has been fastened, including the V2X antennas, GNSS
antenna, Ethernet cable, and I/O cable.
5. Product Appearance
An OBU-352 series package contains the following items:
•OBU-352 x1
•V2X antenna x2
•GNSS antenna x1
•Mini-USB Y-cable x1
•USB charger x1
The photos shown in this document may seem different from actual product. However,
the differences do not affect actual functionalities.

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Figure 1: OBU-352 series package content
Figure 2: EVK-352 series package content

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Figure 3: OBU-352 series complete assembly appearance
6. Functional Block Diagram
Figure 4: Functional block diagram

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7. Electrical Characteristics
7.1. Absolute Maximum Ratings
Over operating free-air temperature range (unless otherwise noted).
Table 1. Absolute maximum ratings
Parameters
Conditions
Min.
Max.
Unit
Storage Temperature
-
-40
105
°C
Supply Voltage
USB0 Vbus
-0.3
6.0
V
POWER (J8.1)
-180
180
V
I/O Interface Voltage
RS232 Receiver *1
-13
60
V
RS232 Driver *2
-6
60
V
CAN0/CAN1 *3
-40
40
V
USB1_Vbus
-2
25/20 *4
V
GPIO1/GPIO2
-0.5
16.5
V
EXT_1PPS
RESET
USB_DN/USB_DP
-0.3
16.5
V
V2X maximum input level
-
-
10
dBm
GNSS maximum input level
-
-
-10
dBm
Note: *1: RS232 Receiver: TX (J8.4), EXT_GNSS_RX (J8.13)
*2: RS232 Driver: RX (J8.3), EXT_GNSS_TX (J8.14)
*3: CAN0/CAN1: CAN0_H (J8.6), CAN0_L (J8.16), CAN1_H (J8.7), CAN1_L (J8.17)
*4: If USB1_Vbus = ON, 25V; if USB1_Vbus = OFF, 20V
Note: (1) Operation outside the Absolute Maximum Ratings may cause permanent device damage. Absolute
Maximum Ratings do not imply functional operation of the device at these or any other conditions
beyond those listed under Recommended Operating Conditions. If used outside the Recommended
Operating Conditions but within the Absolute Maximum Ratings, the device may not be fully functional,
and this may affect device reliability, functionality, performance, and shorten the device lifetime.
(2) All voltages are with respect to network GND.
7.2. Recommended Operating Conditions
Over operating free-air temperature range (unless otherwise noted).
Table 2. Recommended operating conditions
Parameters
Conditions
Min.
Typ.
Max.
Unit
Ta (Ambient operating temperature)
Free-air temp.
-40
25
85
°C
Supply voltage
USB0 Vbus
4.8
5.0
5.2
V
POWER
9
12
42
V
USB1_Vbus output
Vbus voltage
4.8
5.0
5.2
V

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Parameters
Conditions
Min.
Typ.
Max.
Unit
Output current
-
500
900
mA
VIL (Input low level voltage)
EXT_1PPS
RESET
TAMPER
GPIO1/GPIO2
-0.3
-
0.8
V
RS232 *1
0.8
1.5
-
V
VIH (Input high level voltage)
EXT_1PPS
RESET
TAMPER
GPIO1/GPIO2
2.0
-
3.6
V
RS232 *1
-
1.8
2.4
V
RPU (Equivalent pull-up)
EXT_1PPS
32
50
60
kΩ
RESET
1.8
2.1
2.3
kΩ
TAMPER *2
0.9
1.0
1.1
kΩ
RPD (Equivalent pull-down)
TAMPER *3
32
50
60
kΩ
VOL (Output low level voltage)
GPIO1/GPIO2 *4
-
-
0.7
V
RS232 *5
-5
-5.4
-
V
VOH (Output high level voltage)
GPIO1/GPIO2 *4
2.5
-
-
V
RS232 *5
5
5.4
-
V
IOL (low level output current)
GPIO1/GPIO2
-
10
18
mA
IOH (high level output current)
GPIO1/GPIO2
-
-
-10
mA
EXT_1PPS (J8.12) tolerance
Accuracy/Bias
-100
-
100
ns
Precision/Jitter
-30
-
30
ns
Pulse width
15
-
-
ns
V2X antenna gain
5850-5925MHz
-
-
5
dBi
V2X sensitivity
PER ≤10%
-92
-
-
dBm
PER ≤10%,
-40 - +85 °C
-82
-
-
dBm
V2X maximum Input Level
PER ≤10%
-
-
-30
dBm
V2X adjacent channel rejection
-
13
-
-
dB
V2X non-adjacent channel rejection
-
29
-
-
dB
V2X output power
Spectrum mask
Class C
-
-
20
dBm
GNSS antenna gain
Antenna Gain
-
-
-2
dBic
LNA Gain *4
24
27
30
dB
GNSS sensitivity (C/N0)
Acquisition
22
30
45
dB-
Hz
GNSS antenna bias
IANT ≤20mA
3.0
-
3.3
V
GNSS antenna detection current
IANT *6
12
-
58
mA
Note: *1: TX (J8.4) / EXT_GNSS_RX (J8.13)
*2: TRIGGER_SW (SW3.2) = ON
*3: TRIGGER_SW (SW3.2) = OFF
*4: IOL = 10 mA, IOH = -10mA
*5: RX (J8.3) / EXT_GNSS_TX (J8.14)
*6: IANT under Min. = OPEN; IANT over Max. = SHORT; IANT between Min/Max. = NORMAL.

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7.3. Power Consumption
OBU-352 can be powered from a DC power source (e.g., automotive ACC) or from a
mini-USB Vbus power source. OBU-352 will automatically switch to the power source with
the highest input voltage. Changing power source can be done any time before and during
operation, however a reset may be triggered during switch.
Table 3: Power consumption
Condition
Power Consumption
Temp.
Power Source
Voltage (V)
Low *1
Typical *2
High *3
25°C
USB0 Vbus
5
0.52A
(2.60W)
0.53A
(2.65W)
0.94A
(4.70W)
POWER (J8.1)
12
0.24A
(2.88W)
0.25A
(3.00W)
0.45A
(5.40W)
85°C
USB0 Vbus
5
0.65A
(3.25W)
0.66A
(3.30W)
1.03A
(5.15W)
POWER (J8.1)
12
0.30A
(3.60W)
0.30A
(3.60W)
0.50A
(6.00W)
Note: *1: RX only
*2: TX @ 1% duty cycle (CH172, 20dBm, 6Mbps, 750B, 10Hz)
*3: TX @ 100% duty cycle (CH172, 20dBm)
8. I/O Interfaces
8.1. OBU-352
8.1.1. External Interfaces
8.1.1.1. LED
Figure 5: LED
7 6 5 4 3 2 1

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Table 4: LED function
Position
Symbol
Color
Description
1
STATUS
*Note
Green
Amber
Red
Start-up: Blinking Green
Operational: Solid Green
FW upgrade: Amber
Fault: Red
2
POWER
Green
System power indicator
3
1PPS
Green
ON: 1PPS signal HI
OFF: 1PPS signal LOW
Blinking: receiving 1PPS signal
4
EXT_GNSS
Green
ON: 1PPS and NMEA from external GNSS module
OFF: 1PPS and NMEA from internal GNSS module
5
WWAN
Green
ON: LTE module connected to WWAN
6
LED1
Green
User defined LED
7
LED0
Green
User defined LED
Note: Please see TABLE 24:UNEX BSP INTERFACE SETTINGS for Status LED BSP settings. The definition of
each status and its related behavior should be implemented by the user.
8.1.1.2. USB0
Figure 6: USB0 (CN2)
Table 5: USB0 (CN2) pinout
Pin
Symbol
I/O
Level (V)
Description
CN2.1
VBUS
I/O
5.0
USB device mode = USB 5V power input
USB host mode = 5V/900mA power output (e.g., when
connecting an OTG cable)
CN2.2
D-
I/O
0.4
Data -
CN2.3
D+
I/O
0.4
Data +
CN2.4
ID
I
-
USB device mode = NC
USB host mode = Tied to GND (e.g., connecting an OTG cable)
CN2.5
GND
G
-
Ground
USB0 (CN2) on OBU-352 is a USB 2.0 dual role device which can act as either a USB
device or a USB host. The connector of USB0 is mini-B.
When connecting to a computer or a USB charger with a regular mini-USB cable, OBU-
352 acts as a USB device and is powered by the external Vbus. However, when connecting
to another USB device (e.g., USB flash drive) with a mini-USB OTG cable, OBU-352 acts
as a USB host and starts providing 5V Vbus power to the USB device up to 900mA.
The power input/output is determined by the hardware design of the OTG cable.
However, setting of the USB mode and detection of external device should be implemented
by the user.

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8.1.1.3. Ethernet
Figure 7: Ethernet port
Table 6: Ethernet LED function
LED
Symbol
Color
Description
1
LINK
Green
ON = link up, OFF = link down
2
ACTIVE
Yellow
Flashing = activity detected, OFF = no activity
OBU-352 has one Gigabit Ethernet port which supports 10/100/1000 Mbps connection.
It is suggested to use an Ethernet cable compatible with Cat5e or above standard for best
connection speed. The connector type should be RJ45 (TIA/EIA 568B).
The Ethernet port also acts as a 12W PoE (802.3af) PD (powered device) with an add-
on PoE module, POE-301. It supports both mode A and mode B PSE (power sourcing
equipment). POE-301 is not included in product package and should be ordered separately
if needed. Passive PoE is not supported.
8.1.1.4. I/O Port
Figure 8: I/O port (J8)
The I/O port (J8) is the main interface of OBU-352 for console, in-vehicle networks and
peripherals. The I/O port connector is JST SM20B-CPTK-1A-TB, and the mating cable
connector is JST 20CPT-B-2A (see FIGURE 9: I/O PORT CABLE CONNECTOR). A cable
assembly with 24AWG wire should be used to connect to vehicular wire harnesses.
Link
Green
Active
Yellow

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Table 7: I/O port pin map (J8)
Pin No,
10
9
8
7
6
5
4
3
2
1
Symbol
GPIO1
USB1_
VBUS
USB1_
DP
CAN1_H
CAN0_H
GND
TX
RX
RESET
POWER
Pin No.
20
19
18
17
16
15
14
13
12
11
Symbol
GPIO2
GND
USB1_
DN
CAN1_L
CAN0_L
GND
EXT_
GNSS_
TX
EXT_
GNSS_
RX
EXT_
1PPS
GND
Table 8: I/O port pinout (J8)
Pin
Symbol
I/O
Level (V)
Description
J8.1
POWER
I
-
6-48V DC input, 12W
J8.2
RESET
I
3.3
Reset CRATON2 Linux system. (Active LOW)
Low=reset, high or float=running
J8.3
RX
O
5.0
RS232 serial data to DTE (console)
J8.4
TX
I
5.0
RS232 serial data from DTE (console)
J8.5
GND
G
-
Ground
J8.6
CAN0_H
I/O
5.0
CAN0 High. 1KΩsplit termination resistors inside CAN0 port.
J8.7
CAN1_H
I/O
5.0
CAN1 High. 1KΩsplit termination resistors inside CAN1 port.
J8.8
USB1_DP
I/O
0.4
USB 2.0 data +
J8.9
USB1_VBUS
O
5.0
USB Vbus power output 5V/900mA
GPIO508=0, USB1_VBUS OFF;
GPIO508=1, USB1_VBUS ON (default)
J8.10
GPIO1
I/O
3.3
GPIO1
J8.11
GND
G
-
Ground
J8.12
EXT_1PPS
I
3,3
External 1PPS input
J8.13
EXT_GNSS_RX
I
5.0
RS232 serial data from DCE (e.g., an external GNSS device)
J8.14
EXT_GNSS_TX
O
5.0
RS232 serial data to DCE (e.g., an external GNSS device)
J8.15
GND
G
-
Ground
J8.16
CAN0_L
I/O
5.0
CAN0 Low. 1KΩ split termination resistors inside CAN0 port.
J8.17
CAN1_L
I/O
5.0
CAN1 Low. 1KΩsplit termination resistors inside CAN1 port.
J8.18
USB1_DN
I/O
0.4
USB 2.0 data -
J8.19
GND
G
-
Ground
J8.20
GPIO2
I/O
3.3
GPIO2
Figure 9: I/O port cable connector
Female Terminal
JST SCPT-A021GF-0.5
Female Connector
JST 20CPT-B-2A (Rear)
Female Connector
JST 20CPT-B-2A (Front)

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8.1.1.5. 5.9GHz V2X
Figure 10: V2X antenna ports
OBU-352 provides two 5.9GHz V2X antenna connectors. Receptacle (jack) connectors
are FAKRA-Z. User should connect a pair of V2X antenna to this port directly or with a pair
of FAKRA-Z plug extension cables. A pair of FAKRA-Z V2X antennas (EX-55) are provided
in product package.
The V2X antenna ports has a built-in antenna detection function. This detection
mechanism only works with the stock EX-55 antennas provided.
Table 9: V2X antenna status
Antenna Status
Value
Command
OPEN
616-1023
V2X0: cat /sys/bus/iio/devices/iio\:device0/in_voltage4_raw
V2X1: cat /sys/bus/iio/devices/iio\:device0/in_voltage5_raw
NORMAL
410-615
SHORT
0-409
8.1.1.6. GNSS
Figure 11: GNSS antenna port
OBU-352 provides one GNSS antenna connector. This GNSS antenna port is
compatible with both passive and active GNSS antennas. The receptacle (jack) connector
is FAKRA-C. User should connect a GNSS antenna to this port with a FAKRA-C plug cable.
A FAKRA-C active GNSS antenna is provided in OBU-352 package.
V2X1 ANT
FAKRA-Z, 50 Ω
V2X0 ANT
FAKRA-Z, 50 Ω
GNSS ANT
FAKRA-C, 50 Ω

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© 2023 Unex Technology Corporation – Company Confidential
For stable fix acquisition, at least 4 satellites with enough signal strength (C/N0 value
above 30 dB-Hz) are required. If the signal strength goes below 30 dB-Hz, the fix will
become unstable.
8.1.1.7. GNSS Antenna Detection
The antenna detection mechanism is a 2-step process: First check the signal strength.
If the signal strength drops to zero, then check the antenna status flag.
When all the C/N0 values becomes null, it means that the GNSS antenna or its cable
may either become detached or damaged. The GNSS antenna port has a built-in antenna
detection function. The detection mechanism is based on the current consumption of an
active antenna (IANT). If the active antenna consumes less current than 12 mA, then it is
considered as the OPEN status; if the antenna consumes more than 58 mA, then it is
considered as the SHORT status. Anything between 12-58 mA is considered as the
NORMAL status.
The GNSS 3.3V antenna bias will be continuously supplied in OPEN/NORMAL status.
Once the SHORT status is triggered, the SHORT flag will persist, and the 3.3V bias will be
turned off until the reset of the GNSS module. After the reset of the GNSS module, the
detection process will start all over again.
It is possible for a good active antenna to be reported OPEN because it consumes less
current than 12 mA, or a good passive antenna to be considered SHORT because it is DC
shorted (e.g., a slot antenna). However, as long as there are more than 4 satellites with
enough signal strength (C/N0 value above 30 dB-Hz), the GNSS is in good state.
The antenna status flag is reported in a proprietary NMEA message:
$PSTMANTENNASTATUS,<status>*<checksum><cr><lf>
where <status> can be:
•0 - The antenna current is in the normal range (NORMAL)
•1 - The antenna current is below the normal range (OPEN)
•2 - The antenna current is above the normal range (SHORT)
Table 10: GNSS antenna status
Antenna
Status
Current
Consumption (mA)
3.3V bias
NMEA Sentence
OPEN
< 12
ON
$PSTMANTENNASTATUS,1*4C
NORMAL
between 12- 58
ON
$PSTMANTENNASTATUS,0*4D
SHORT
> 58
Turned OFF once triggered
$PSTMANTENNASTATUS,2*4F

Doc. No: Unex-QSG-21-001
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8.1.2. Internal Interfaces
8.1.2.1. Mini PCIe Port (Optional)
A USB 2.0 device with mini PCIe form factor can be connected to the mini PCIe port
(J6). However please note that although the form factor is mini PCIe, the PCI Express
interface is not available.
Figure 12: Mini PCIe Port (J6)
Table 11: Mini PCIe pinout (J6, Row 0)
Pin
Symbol
I/O
Level (V)
Description
J6.1
WAKE#
I
OC
Sierra MC series: Wake host. (OC output. Active LOW)
J6.3
5V
O
5.0
5V power output for SOM-300 family
J6.5
5V
O
5.0
5V power output for SOM-300 family
J6.7
NC
-
-
Not connected
J6.9
GND
G
-
Ground
J6.11
NC
-
-
Not connected
J6.13
NC
-
-
Not connected
J6.15
GND
G
-
Ground
-
KEY
-
-
Mechanical Key
J6.17
UART2_TX
O
3.3
UART transmit data output for SOM-300 family
J6.19
UART2_RX
I
3.3
UART transmit data input for SOM-300 family
J6.21
GND
G
-
Ground
J6.23
NC
-
-
Not connected
J6.25
NC
-
-
Not connected
J6.27
GND
G
-
Ground
J6.29
GND
G
-
Ground
J6.31
NC
-
-
Not connected
J6.33
NC
-
-
Not connected
J6.35
GND
G
-
Ground
J6.37
GND
G
-
Ground
J6.39
3.3 Vaux
O
3.3
Max 1100mA
J6.41
3.3 Vaux
O
3.3
Max 1100mA
J6.43
GND
G
-
Ground
J6.45
5V
O
5
5V power output for SOM-300 family
J6.47
5V
O
5
5V power output for SOM-300 family
J6.49
1PPS
O
3.3
GNSS 1 pulse per second input
J6.51
TAMPER#
O
3.3
0=Tamper tripped, 1=Normal operation.
SW3.2 ON: J6.51 close to OBU-352 tamper
SW3.2 OFF: J6.51 open from OBU-352 tamper

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Table 12: Mini PCIe pinout (J6, Row 1)
Pin
Symbol
I/O
Level (V)
Description
J6.2
3.3 Vaux
O
3.3
Max 1100mA
J6.4
GND
G
-
Ground
J6.6
NC
-
-
Not connected
J6.8
UIM PWR
O
3.0/1.8
SIM card power
J6.10
UIM_DATA
I/O
3.0/1.8
SIM card data
J6.12
UIM_CLK
O
3.0/1.8
SIM card clock
J6.14
UIM_RESET
O
3.0/1.8
SIM card reset
J6.16
NC
-
-
Not connected
-
KEY
-
-
Mechanical Key
J6.18
GND
G
-
Ground
J6.20
W_DISABLE#
O
OC
1 = Modem on; 0 = Modem off (Sierra MC series)
J6.22
PERST#
O
OC
Signal rising edge (0 -> 1) will reset mPCIe module
J6.24
3.3Vaux
O
3.3
Max 1100mA
J6.26
GND
G
-
Ground
J6.28
NC
-
-
Not connected
J6.30
NC
-
-
Not connected
J6.32
NC
-
-
Not connected
J6.34
GND
G
-
Ground
J6.36
USB_D-
I/O
0.4
USB 2.0 differential data (-)
J6.38
USB_D+
I/O
0.4
USB 2.0 differential data (+)
J6.40
GND
G
-
Ground
J6.42
LED_WWAN#
I
OC
WWAN LED signal. OC input. Active LOW.
J6.44
NC
-
-
Not connected
J6.46
DPR
O
OC
Dynamic Power Control (Sierra MC series)
High: No SAR backoff; Low: Backoff 1
J6.48
NC
-
-
Not connected
J6.50
GND
G
-
Ground
J6.52
3.3 Vaux
O
3.3
Max 1100mA
8.1.2.2. SIM Slot (Optional)
If a WWAN (LTE) module is connected to the mini PCIe port, the sim card should be
installed. The SIM slot has a metal flip lid. It is necessary to slide the lid into “Unlock”
position before open it.

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Figure 13: SIM slot (J7)
Lock
Unlock
Open