is it possible that stdriveg600 high side driver loses pulses for high duty cycle?

[FCarl.3]

hello,

I bought the evaluation board EVSTDRIVEG600DG and I made the circuit in the figure below.

 

I have the following problem:

with a 50khz pwm signal (Dead Time=200ns) and a duty cycle of 90% with a power supply around 100v, the high side driver of the ic stdriveg600 starts to lose pulses and in general work in bad way.

What could be the reason?

[Javier1]

I am not able to read it properly due to picture quality.

Whats the value of your Bootstrap capacitors? 47nF?

¿Are they ceramic?¿Are they rated for 2 times your operating voltage(spikes)?

Maybe they are too big? Thus not fully charging in between cycles

[FCarl.3]

The bootstrap capacitors mounted on evaluation board are 47nF in parallel with 1uF.

[Javier1]

im talking about C13 and C17, i dont see any pararell 1uF in your schematic.

If i were you i would try to reduce the bootstrap capacitance values.

[FCarl.3]

C21 is in parallel with C17 and C12 is in parallel with C13.