Help with replacing transistor with faster speed

[globalone]

Hello,

I am building a fast switch driver circuit . Switching speeds are similar to the bipolar design.

The circuit provides 35nSec rise and fall times. This circuit will turn the switch on and off within 50nSec.

My target is to have faster speed for Turn-On/Turn-Off . 35nSec would be okay for the T-On/T-OFF , but I want to reach between 15nSec ~ 30nSec.

Do you think that BSS84DW (https://www.electro-tech-online.com/custompdfs/2013/06/ds30204.pdf) can be replaced with NDC7003P or NDS9948 ?.

What speed would i reach If I am going to use NDC7003P or NDS9948 ?.
https://www.electro-tech-online.com/custompdfs/2013/06/NDC7003P.pdf
https://www.electro-tech-online.com/custompdfs/2013/06/NDS9948.pdf

Are you familiar with (DUAL P-CHANNEL ENHANCEMENT MODE MOSFET). I have a working circuit that accept a logic input (0V/+5V) to bias a switch VC1 & VC2 (0V/-40V).

I had to use BSS84DW (https://www.electro-tech-online.com/custompdfs/2013/06/ds30204.pdf) , but the circuit provide a switching speed on and off within 50nSec and rise/fall 35nSec.


I have already found a replacement to BSS84DW with NDC7003P (https://www.electro-tech-online.com/custompdfs/2013/06/NDC7003P.pdf) which should be faster , but I am not sure if it will use the same resistors , capacitors etc..

I want to know what should I get a Turn-OFF/Turn-ON speed if I am going to use the new PowerTrench MOSFET (NDC7003P) ?.

Please see the Driver circuit of the spdt switch.
https://obrazki.elektroda.pl/3646151600_1371494410.png

I really appreciate your help


Ghassan

 

[ronv]

I'm not sure the 7003 will be as fast. It has higher gate capacitance. It may be hard to find a 60 volt FET that is much better than the one you have. Look for one with lower capacitance specs. Might be better of with an old fashion bipolar transistor and a smaller pull up to the -40 volts.