Higher current SimpleFOC board


I’ve started designing a PCB for a higher current board with an integrated µcontroller. If you have any tips or things that I have to keep in mind, let me know!

Gate driver: DRV8305
µcontroller: Atmega328P-AU
MOSFETs: IRL3803 (This will be swapped for SMD, any suggestions?)
encoder: external AS5600 board


Carelsbergh Stijn

I realise chips are very subjective, but i’d want something a bit beefier than atmega328. The 2k of sram is a pita and 16mhz?. My choice would be esp32 or stm32f1xx (or lower higher spec). I prefer the former but the latter is easier to source/assemble.
I’d breakout the spi pins just in case you and the as5600 don’t get along!

I guess you’ve not figured out the shunts yet. And not connected the in1,2,3 (I guess you’ll be opting for 3PWM not 6PWM)

Have you checked out the @David_Gonzalez dagor/janus board? I think he uses the same driver. I think he connects the mcu to drv8305 using SPI in order to configure driver.

DRV8305 looks like a really cool driver. Let us know how it goes!

I would also go for a beefier MCU but I guess that depends how you intend to use the driver. In 1PWM or 3 PWM mode, the ATMega could be cool. For 6 PWM or to do current sensing on the MCU I would use something else.

In particular the ESP32 and STM chips have dedicated PWM modes for 6 PWM control so they can do the complements and dead-time insertion, and even sync up the ADC if I recall correctly.
On the other hand, why pay for an driver like the 8305 that can do all those things itself if you want to handle it on the MCU?

Oh, and for SMD MOSFETs take a look at Alpha & Omega Semiconductors. They have some really nice ones.

Regards from Vienna,