FEDEVEL
Platform forum

Ben , 06-26-2026, 02:58 PM

So I have a design I am doing where there is 1 central board (referred to as the motherboard) and then I have several boards being mounted and electricall conneted to it. Some of these are BLDC motors, some are buck and boost converts, etc.

However I have one board that is going to be a custom made GNSS Reciever and is an RF design. Are there any mounting considerations I should keep in mind when picking the way that this board gets mounted on the motherboard such as a specific type of connector, only 1 point of contact with gnd on the rest of the board etc

, 06-26-2026, 03:03 PM

🤖 In the meantime, here’s a response from the [FEDEVEL AI HW Assistant]().
It helps to find relevant resources for your question, but it may make mistakes as it’s still in early development.

This is the response from the AI Assistant:
For your multi-board design with an RF GNSS receiver, here are key considerations from the video knowledge base:

1. **Shielded Connectors & Grounding**:
- Use connectors with continuous 360° shielding (like properly designed USB-C or SMA) for RF signals. Spring contacts on shielded connectors should make low-impedance contact to the enclosure/motherboard ground plane. Cheap connectors often have poor EMC performance ([source](https://www.youtube.com/watch?v=gHF5JyJF-N4&t=4364)).
- Avoid single-point grounding between boards. Multiple ground connections (every other pin in high-speed connectors) reduce ground bounce and EMI. A single return path creates voltage noise and radiation ([source](https://www.youtube.com/watch?v=X-qubBLJDD8&t=1311)).

2. **Mounting Considerations**:
- Use multi-point RF bonding between boards and chassis - spacing < λ/10 at your highest frequency. For GNSS (1.5GHz), this means < 2cm spacing between ground connections ([source](https://www.youtube.com/watch?v=yHn-XOcvJOY&t=0)).
- Consider capacitor/resistor networks (1-10nF caps or 1-10Ω resistors) at mounting holes for RF bonding without creating DC ground loops ([source](https://www.youtube.com/watch?v=gHF5JyJF-N4&t=3618)).

3. **Isolation**:
- Physically separate GNSS board from BLDC motor drivers and switching converters.

, 06-26-2026, 03:03 PM

Use separate ground regions on motherboard connected at single point under GNSS module ([source](https://www.youtube.com/watch?v=vALt6Sd9vlY&t=1483)).
- Implement shielding cans over GNSS circuitry with fingerstock gaskets making contact to motherboard ground plane ([source](https://www.youtube.com/watch?v=gHF5JyJF-N4&t=4655)).

4. **Connector Layout**:
- Place GNSS board connectors near edge of motherboard with direct path to chassis ground. Route RF traces on motherboard as stripline between ground planes ([source](https://www.youtube.com/watch?v=LDe3ZJ16HxQ&t=232)).
- Use coaxial transition (via fence around connector) when passing RF through motherboard layers ([source](https://www.youtube.com/watch?v=_8YzqllIoJ4&t=2766)).

For implementation: Test different bonding configurations (direct grounds vs. capacitive/resistive) during EMC testing as resonances can vary between prototypes ([source](https://www.youtube.com/watch?v=gHF5JyJF-N4&t=3256)).

You can continue chatting with the AI Assistant here:
https://fedevel.com/hw-assistant

Robert Feranec , 06-30-2026, 05:23 AM

The video with Keith may help. I dont know about any list of universal rules when building a system from multiple boards - usually people will tell you "It depends"