mosfet gate driver problems

Hi
I am trying to switch a mosfet IRPE50pbf (total gate charge 220nC) using driver IXDN504PI( 4 A max gate driver). The gate drive circuit was running perfectly when the switch was IRF840( total gate charge =66nC).However when the swich is IRFPE50PBF,when the drain to source voltage is increased beyond 100V, the gate power supply gets affected. At 0V Drain to source, the gate voltage is 15V and 0.03A is drawn from power supply. Now when i increase the drain source to around 300V, the gate voltage dips to 10V and around 0.8A is drawn ( the power supply rating is 30V,3A). The effect is more, when the load is high. When i connected another power supply as source for for gate driver, the supply voltage itself started increasing with increase in drain to source voltage.

What is problem , is it that driver is not able to suply the gate charge current. But according to my calculations it requires 2A which IXDN504PI is able to supply.
Also why is two different power supplies to gate driver behaving differently (ie. in one voltage is dipping and in another voltage is rising).THe power circuit involved is a simple boost converter.

Thanks

When you say you're varying the drain voltage, that means you have a load between the DC bus and the drain, right?
What is your operating frequency? Are you using any gate resistors?

Hi

I am using mosfet in simple boost converter topology. The load is resistive 450ohms(drain source varies from 0-450V). The switching frequency of mosfet is 50KHz.I am using 4.7 ohms gate resistor.

The boost is synchronous or asynchronous? It is simulation or experiement?
The phenomenon is strange.

Did you decouple the power supply leads of the driver with sufficient very low ESR capacitors? Think of many X7R 100nF (or larger) capacitors in parallel directly between the power supply leads of the driver (to minimize parasitic inductance)? By doing this, the peak current is taken from these capacitors, making it easier for the power supply.

At present i have used 10uf electrolytic cap along with 0.1uf tantalum cap in parallel to decouple the power supply. I will try using more and see the effect.