Convergence Problem

Dear All,

Right now, I am using a P channel MOSFET spice model from Toshiba "SSM3J15FU". Based on its datasheet test circuit i just tried to simulate the model.

But i am getting the following error "ERROR(ORPSIM-15138): Convergence problem in transient analysis at Time =  170.4E-06.
         Time step =  266.2E-21, minimum allowable step size =  1.000E-18 ".

Could you please some guide me, how to solve the issue?.

Note : If i use a series gate transistor 1K on its gate control signal, the issue is getting resolved.

I just want to know, how the gate resistor is making its work..

Thanks, US