CMOS driving a transistor

[DeonG]

I have build a pulse generator using a CMOS monostable multivibrator. I am trying to interface with a transistor (2n2222) using an emitter-follower configuration. It produces a very sharp switch-on edge, however the switch-off edge forms a transient like response between 2 pulses. I therefore do note get a sharp pulse. A response by anyone with experience on this will be much appreciated.

P.S. pulse width≈3.5µsec; f≈25kHz; V=6.8V

 

[MikeMl]

What kind of load are you driving?

50Ω to ground?

How much capacitance (coax cable)?

 

[DeonG]

I eventually want to drive a MOSFET. I therefore want to translate the pulse to a 18V pulse to switch the MOSFET. It is critical to maintain low power in the application.

 

[MikeMl]

Ok, so you have a 0V to 6.8V pulse (CMOS output) that you want amplify to a 0V to 18V to drive into a a very high resistance (gate resistance) and a very high capacitance (gate capacitance of a typical Power NFET)?

We wouldn't be playing twenty questions if you just posted your schematic.

 

[DeonG]

Attached please find a circuit diagram