I'm designing a BoosterPack to evaluate GaN devices with the help of a microcontroller.


             lmg5200 boosterpack lcd


The kit will have a GaN half-bridge that can control an output of 20V and 10A.

Currently the prototype can control switching frequency and duty cycle.

I'm also planning a stretch goal to integrate the design with LabView. You can then use this as a part of a test setup.




The Design Exists


I have a working prototype. I modded an existing LMG5200 evaluation kit a while ago.

I removed the discrete PWM generator and replaced it with microcontroller managed signals.

hercules and LMG5200


This proof of concept works, both electronics and firmware. I can make a more sturdy version now.

The switching layout is fully based on the design guidelines and the evaluation kit's PCB.

Because of the high switching frequencies and high currents, that part of the design is critical.

I'm trying to place all components similar to the application notes. This will be my first 4-layer PCB design.




I have the schematic ready.

I had to create a few components and footprints (both for LMG5200 and rotary encoder, footprint only for the inductor).

LMG5200 Hercules BoosterPack schematic

For the PCB, I have a provisional layout. I haven't routed a single trace yet.

But I have uploaded that intermediate status to OSHPark to get an idea of how this device will look like.

Before doing that routing, I first have to verify if I can source all the components that I'm planning to use.

In particular the SMD 360° rotary encoder may be a tricky purchase.


board bottom


LMG5200 footprint


To be continued...


Related Blogs
Hercules LaunchPad and GaN FETs - Part 1: Control Big Power with a Flimsy Mouse Scroll Wheel
Hercules LaunchPad and GaN FETs - Part 2: Make a BoosterPack
Hercules LaunchPad and GaN FETs - Part 3a: BoosterPack Layout - Reference Design
Hercules LaunchPad and GaN FETs - Part 3b: BoosterPack Layout - my version
Hercules LaunchPad and GaN FETs - Side Note A: BoosterPack Layout - Custom KiCad Parts
Hercules LaunchPad and GaN FETs - Side Note B: Look at the PCB
Rotary Encoders - Part 1: Electronics
Checking Out GaN Half-Bridge Power Stage: Texas Instruments LMG5200 - Part 1: Preview
Rotary Encoders - Part 4: Capturing Input on a Texas Instruments Hercules LaunchPad with eQEP
Vintage Turntable repair: Can I fix a Perpetuum Ebner from 1958 - part 4 - Hercules LaunchPad Enhanced PWM try-out