BOOSTXL-DRV8323RH: RC Snubber circuit and Vds slew rate relationship ?

Tool/software:

Hi,

I have custom board with IDRIVE setting (measured 1.64v) which is VI4 120/240mA and MOSFET's Qgd is ~8nc, therefore by calculation the tRISE should be 66ns and tFALL 4ns, however actually measured is ~ 300ns.

My question is why it's huge different ? because of my RC Snubber circuit ? 

IDRIVE setting measured 1.64v

MOSFET Qgd

> 300ns measured on oscilloscope 

RC Snubber circuit 

Danny