It seems almost every product these days needs to have some level of connectivity be it for end user access on their smart phone, connecting with other similar devices, or providing diagnostic data for real-time health monitoring. What all these requirements have in common is you now have RF sensitive circuits that you need to manage. Learn some quick tips and tricks to help you design and manage RF circuitry in your PCBs.

1. Orlen Bates
Sr. Application Engineer
RF Designs the Wave of the
Future
9/4/2018 1

2. Agenda
• What are RF Waves
• Design Considerations
• Best Practices
• Examples
• Q&A
9/4/2018 2

3. What are RF Waves?
Radio frequency (RF) refers to the rate of
oscillation of electromagnetic radio waves in
the range of 3 kHz to 300 GHz, as well as
the alternating currents carrying the radio
signals. This is the frequency band that is
used for communications transmission and
broadcasting.
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4. Respect the Wave

5. Design
Considerations
1. Health and Safety
Requirements
2. Environment Conditions
3. Product Lifecycle
Expectations
4. PCB Stack-up & Material
Usage

6. Best Practices
RF Ground
• Proper grounding is KEY
• Connect the ground pins of the RF
components to the RF ground plane as
short as possible
• If the board includes multilayer ground
planes, provide many ground vias
wherever the signal trace makes a
transition from one side of the plane to the
other.

7. Best Practices
RF Ground, RF Ground and say it
again RF Ground
Consider the use of an RF fence /
cover

8. Best Practices
Plating / Copper
• Use gold plating for RF components
created from etch
• No copper inlands near the RF circuitry
• No copper thieving near the RF circuitry
• Ground both ends of copper pours, and
stitch many vias wherever possible
• Separate RF planes from all other
planes

9. Best Practices
SMT vs. Thru Hole
• Use SMT parts for RF
• If thru-hole is required backdrilling should
be used with thru-hole components and
vias. This will remove that unwanted
antenna.

10. Best Practices
Stackup / Materials
• Multi-layer PCB is best
• Always provide continuous grounds
under traces
• Consider material selection carefully.
Standard FR4 may not meet your needs
Source: Isola

11. Best Practices
Vias
• Use isolated vias for separate portions of
a filter or matching network
• Use least number of vias in RF routing,
max number of vias in RF grounding

12. Best Practices
Routing
• Orient sensitive traces orthogonally
• Use short traces between the crystal and
RF device
• Keep interconnect traces separated as
much as possible
• Keep trace lengths to a minimum

13. Best Practices
Routing, Printed Circuit/Selection
• Adhere to proper corner routing
• Use wire-wound inductors whenever
possible and avoid using printed down
circuit parts unless needed
• Place inductors, coils and a planer
isolated from each other

14. Best Practices
Simulation
• Simulation is strongly recommended if
RF component is being printed / down as
part of the board

15. Key Takeaways
• Ground. Ground. Ground.
• Carefully consider RF implementation as
design choices will have a significant
impact on cost and complexity
• Understanding the effects RF circuitry
has on your design is half the battle…oh
and ground.

16. Demo

17. 9/4/2018 Your PDN Gives Your Board Life 17
Thank you for joining us today.
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