# Hardware overview
Source: [https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html)
The Qualcomm RB3 Gen 2 Development Kit is available as a Core kit and a Vision kit. Both
kits feature a system-on-module (SoM) that integrates a Qualcomm system-on-chip (SoC).
[QCS6490](https://docs.qualcomm.com/bundle/publicresource/topics/80-23889-1/device-description.html) and [QCS5430](https://docs.qualcomm.com/bundle/publicresource/topics/80-23889-1/device-description.html) SoCs are supported. The SoM is mounted
to an interposer that is connected to the mainboard using a 500-pin connector. The
mainboard includes multiple connectors to support a variety of different peripheral
interfaces and stackable mezzanine cards. The Vision kit includes everything in the Core
kit plus the Qualcomm Vision mezzanine board, a high-resolution main camera, and a
low-resolution tracking camera.
Table : Kit components
| Core kit | Vision kit |
| :---: | :---: |
|
|
Note: The RB3 Gen 2 Vision kit includes cameras with protective lens covers. Remove these
covers before using the kit.
### Mainboard and interposer block diagram
The following block diagram
shows the RB3 Gen 2 mainboard and interposer. Connectors are shown in dark blue.
Some connectors are on the interposer board and some on the mainboard. Knowing the
placement of these connectors is useful in configuring and debugging them easily and
effectively.
Figure : Mainboard and interposer block diagram
Table : Hardware features of the Core kit
| **Feature** | **Component name** | Interface | **Details** |
| :---: | :---: | --- | :---: |
| DSI to HDMI bridge | Lontium LT9611UCX | HDMI Type-A connector | 4K at 30-Hz HDMI support with I2S audio |
| USB hub | Genesys GL3590 | 2x USB Type-A connectors | USB 3.1 Gen2 10Â Gb 4-port hub controller |
| USB to LAN | ASIX AX88179 | RJ45 connector | USB 3.0Â Gb to 1Â Gb Ethernet controller |
| Audio amplifiers (2) | Qualcomm WSA8835 | Header pins (2) on interposer | Class-D SoundWire audio amplifier |
| CAN bus controller | Microchip MCP2518FD | Pins on LS1 connector | External CAN-FD controller with SPI |
| Sensor | TDK ICM-42688-P | Sensor on mainboard | 3-axis gyroscope and 3-axis accelerometer |
| On-board digital microphone | TDK T5818 | Microphone on mainboard | PDM digital MEMS microphone |
| USB host/Device port | USB Type-C | Type C connector | USB Type-C with display port (direct connect to processor) |
| Input power | DC power input | Barrel jack connector | +12-V from wall supply |
| microSD storage | microSD card | microSD card tray | microSD card tray |
| WLAN/Bluetooth antenna | Antenna0 | Printed antenna on mainboard | 2.4Â GHz/5Â GHz printed antenna |
| WLAN/Bluetooth antenna | Antenna1 | Printed antenna on mainboard | 2.4Â GHz/5Â GHz printed antenna |
| Debug UART | FTDI UART to USB converter | microUSB connector | Connector with FTDI USB to UART converter |
| DP display | DP display output | Micro DisplayPort connector (on interposer) | Display only, not including touch or backlight control |
| GNSS | SDR735G chipset | RF connector for external antenna on interposer | GNSS/GPS support |
| USB 2.0 | USB1 port from SoC | Micro USB connector on interposer | Additional USB port for host/device mode |
| Second Ethernet port | From QPS615 PCIe expander | IX Ethernet connector on interposer | 2.5 GbE from PCIe |
| Third Ethernet port | From QPS615 PCIe expander | IX Ethernet connector on interposer | 10 GbE from PCIe (not installed by default, special order) |
| Camera port 1 | From chipset | 30-pin flex connector | Support for C/D-PHY camera |
| Camera port 2 | From chipset | 30-pin flex connector | Support for C/D-PHY camera |
## Mainboard power
**Prerequisite:** RB3 Gen 2 Development Kit is loaded with a Linux image. If image is
not loaded, device enters emergency download mode when powered on.
Figure : Locations of power adapter input and Power button
Connect the +12 V power adapter and press the Power button to boot up the board. The
processor powers up and loads the boot image from internal storage UFS.
- To reboot manually, press and hold Power for at least 20 seconds.
- To view the bootup message logs, connect the host to the debug port (baud rate
115200) of the RB3 Gen 2 Dev Kit using a microUSB cable and use a serial
terminal such as PuTTY. The green light besides the power plug will illuminate.
Note that the device will not boot with only the USB Type-C cable connected.
Ensure to connect the power adapter.
## Status LEDs and buttons
Source: [https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html)
The following figure shows the LEDs and buttons on the RB3 Gen 2 mainboard.
Figure : [L] Top view of mainboard LEDs and buttons, [R] bottom view
Additional notes:
- LED for Wi-Fi status is yellow.
- LED for Bluetooth status is blue.
- F\_DL button is used for emergency boot.
- In addition to volume control, Vol- is also used to reset the device.
See [Table : Interposer DIP switch selection](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_dip_switches.html#rb3_dip_switches__dip-switch-interposer) for more
information on the boot config and user controllable DIP switches.
## Mainboard and interposer connectors
Source: [https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html)
The following figures show the location of the different connectors on the mainboard and
interposer. The image at left shows the connectors from the top view of the mainboard.
The image at right shows the connectors from the bottom view of the interposer board
(outlined in yellow) attached to the mainboard. The bottom view is shown with the
baseplate removed.
Figure : [L] Connectors on top view of mainboard, [R] bottom view of interposer (*in yellow*) and mainboard
Low-speed connectors (LS1, LS2, LS3) and high-speed connectors (HS1, HS2, HS3)
provide various functionalities including UART, SPI, camera CSI, interrupt signals, DC
power, additional GPIOs, and more. Click [here](https://docs.qualcomm.com/doc/80-70014-251/topic/low_speed_high_speed_expansion_connectors.html) to see details for
the low-speed and high-speed expansion connectors.
## Vision mezzanine
The Vision mezzanine supports interfacing cameras to the RB3 Gen 2 platform via two,
second-generation gigabit multimedia serial link (GMSL2) camera inputs and five CAM/CSI
camera ports. This mezzanine also provides four DMICs, an IMU, compass/magnomenter, and
a pressure sensor.
Figure : Vision mezzanine
Figure : Vision mezzanine and mainboard block diagram
The following key components are supported on the Vision mezzanine:
**Camera**
- Two GMSL2 camera inputs (using MAX9296A), CSI4 and CSI5. Lables on board (GMSL1 and
GMSL2) are connector names only. Both inputs are GMSL2 technology.
- Five CAM/CSI camera ports with identical pinouts: CSI0 is split into two cameras
(CAM0A and CAM0B)
- CAM3 connector includes an option for a higher supply voltage of 5Â V and
accommodates the Panasonic TOF camera
- Main camera (IMX577); part number: CMK-IMX577-B-V2.0, connect to CAM3
- Tracking camera (OV9282); part number: CMK-VR-OV9282-V1.0, connect to CAM0A
**Sensors**
- TDK ICM-42688-P IMU (located on the back side of the board)
- AKM compass/magnetometer AK09919
- TDK pressure sensor (ICP-10111)
**Audio**
- Four digital PDM mics that interface directly with the RB3 Gen 2 platform
- Speaker connectors on the mezzanine are inactive. They are replaced by the speaker
connectors located on the interposer. For more information, see [Mainboard and interposer connectors](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html#rb5_mainboard_connectors_0).
## Sensors
Source: [https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html)
Sensors are available on the mainboard and the vision mezzanine. The following table
lists the sensor details and identifies the appropriate DIP switch for each sensor:
| Placement | Sensor part | Sensor type | DIP switch | Name | Details | Default |
| --- | --- | --- | --- | --- | --- | --- |
| Mainboard | ICM42688 | Inertial Measurement Unit (IMU) sensor: Accelerometer and Gyroscope | DIP\_SW\_0 (pin 5) | SENSOR\_IMU\_TOGGLE |
| ON |
| | | | | | | |
| | | | | | | |
| | | | | | | |
Only one IMU sensor can function at a time. If both sensors are enabled, only
the Vision mezzanine IMU functions. See [DIP switches](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_dip_switches.html) for DIP
switch locations.
## Ethernet
The RB3 Gen 2 Development Kit provides a gigabit Ethernet interface on the mainboard
through an RJ45 connector and a 2.5GbE Ethernet interface on the interposer board
through an IX connector. An adapter cable, which is not part of the kit, is required to
use the IX connector. An adapter cable is available as an optional accessory for
additional purchase.
Figure : [L] Ethernet connector on top view of mainbaord, [R] Ethernet connector on bottom
view of interposer (in yellow)
Use the following snippet of the mainboard and interposer diagram to follow along with a
high-level description of the Ethernet functionality, flow, and components in the RB3
Gen 2 Development kit. Click [Figure : Mainboard and interposer block diagram](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html#hardware_overview__fig_twb_t3t_51c) to
see the full diagram. **(1)** On the interposer board, the PCIe1 2L signals are
connected to the QPS615 (PCIe bridge). **(2)** SGMII signals from the QPS615 are
connected to QEP8121 PHY and terminated to the IX connector supporting 2.5GbE. **(3)** Based on the DIP SW 3 (bit 2) settings, the QPS 1 lane PCIe signals are connected to
either PCIe to USB (uPD720201) where it is converted to USB or routed straight to the
500-pin connector. The default switch position is to select the path via PCIe to USB
(uPD720201). The mainboard has the USB 3.1 Gen2 Hub **(4)** along with USB to LAN
(AX88179) which is terminated to the RJ 45 connector.
## Emergency download (EDL) mode
Source: [https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html)
The RB3 Gen 2 platform enters EDL mode after power up if there is no image on the device
or if it is corrupted. In some situations, you want to force the device into EDL mode to
download software because EDL mode allows for the flashing of software images. To force
the device into EDL mode, do the following:
1. Connect the device to a +12 V wall power supply.
2. Press and hold the **F\_DL** button.
3. Connect the device to the host system through the USB Type-C connector.
4. Release the **F\_DL** button. The device should now be in Qualcomm download
(QDL) mode. For this task, QDL is used interchangeably with EDL.
5. To verify whether the device has entered the QDL mode, run the following command
on the host:
lsusbCopy to clipboard
**Sample output**
`Bus
002 Device 014: ID 05c6:9008 Qualcomm, Inc. Gobi Wireless Modem (QDL
mode)`
## Mainboard RF antennas
Source: [https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html](https://docs.qualcomm.com/doc/80-70014-251/topic/rb3_hardware_overview.html)
The RB3 Gen 2 mainboard uses two dual-band, 2.4Â GHz/5Â GHz/6 GHz, WLAN/Bluetooth
technology printed antennas on the mainboard. To avoid detuning the antennas, use nylon
standoffs for mounting holes and check that there is no metal directly above or below
the antennas. QCS6490/QCS5430 support 2 × 2 MIMO with 2x Wi-Fi antenna ports and 1x
Bluetooth technology antenna port (Bluetooth technology antenna can be dedicated or
shared with one of the Wi-Fi antennas). The current SoM uses a shared Wi-Fi/Bluetooth
technology approach on RF chain 0. The SoM has the option to route RF signals through
the board-to-board connector to the mainboard to eliminate the need for external coaxial
cables (current configuration).
Figure : Dual-band RF antennas on the mainboard (bottom view)
If higher performance external antennas are preferred, they can be plugged into the
connectors on the interposer using an Ipex MHF-SW 23 series cable. A GNSS connector is
also availabe. Use Ipex MHF-SW 23 series cable for GNSS and an external antenna (not
included in the kit).
Figure : Dual-band RF antenna and GNSS connectors on the interposer
Last Published: Jan 28, 2026
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