Anycubic Chiron

Hope this helps anyone, starting a light lower than Vref and active cooling is recommended for drivers

Bigtreetech TMC2208 V3.0 Rsense 110 mOhm

X and Z Double axis
- Nema 17 42HD4027-01 - 1.5A rated current - 1.29v Vref

Extruder
- Nema 17 42HD3016-01 - 1.2A rated current - 1.03v Vref

Y axis
- Nema 17 42HD48-1804S - 1.8A rated current - 1.55v Vref

used this calculator:

https://printpractical.github.io/VrefCalculator/

Fystec calculator gave values over the top and making motors overheat and skip

This is working for me, Trigorilla Board, BTT TMC2208 V3 stepper drivers and stock Chiron motors.

Take this as a startup point.

I am in no way responsible for any damage to your hardware.