Clean 20Mhz square wave at 45 volts ... possible???

[royalmp2001]

Hi everyone,
Been trying to see if anything like this is possible.
I have got a IRF610 mosfet to switch at 1Mhz at 33 volts but the waveform is not clean and looks more like a distorted triangle wave. Going up to 2Mhz the voltage swing drops completely.
I know I could use a faster Mosfet...
I am driving the gate from a 9v function generator via a 100 ohm resistor. The mosfet load is a 750 ohm resistor connected from +33volts to drain and I have a 50Mhz oscilloscope connected across the load. I also have a 15k resistor connected from gate to source.
Thoughts, anyone.?
Different resistor values or additional components?
Thanks

 

[Bluejets]

Gate capacitance is probably causing grief.
Maybe use a mosfet driver?

 

[Alec_t]

Many function generators are intended for driving low current loads only. As Bluejets says, a dedicated FET driver may help, since it is designed to handle high current needed to charge/discharge the gate capacitance quickly.

 

[duke37]

I do not think this is possible. You need several harmonics to get anything near a square wave so will need to amplify at least 100MHz.