Maker Pro
Maker Pro

Double gate Mosfets

Hi all!

I need to build an ultra low noise cascode amplifier and I want to use
a double gate mosfet to gain better performances with respect to
jfets.
I need a very low gate leakage current, because it worsens the SNR.

I found some interesting components made for RF purposes by NXP, but
all have protection diodes and also a bias network integrated in the
package.
I need to find a mosfet with naked gates. I know they're very
sensitive to ESDs, but I need very low leakage and I can't tolerate
the leakage of the protection diodes.

Can someone help me?
Thanks!
Marco
 
M

MooseFET

Jan 1, 1970
0
Hi all!

I need to build an ultra low noise cascode amplifier and I want to use
a double gate mosfet to gain better performances with respect to
jfets.
I need a very low gate leakage current, because it worsens the SNR.

I found some interesting components made for RF purposes by NXP, but
all have protection diodes and also a bias network integrated in the
package.
I need to find a mosfet with naked gates. I know they're very
sensitive to ESDs, but I need very low leakage and I can't tolerate
the leakage of the protection diodes.

Can someone help me?

Try Calogic. They make small signal MOSFETs without protection
diodes.
 
What frequency? What bandwidth?

John

Hi John,
thanks for replying.
Ok, the mosfet has to be used in a charge sensitive preamplifier
configuration. At the present moment I'm using a jfet before an op-amp
with a drain resistance of 1Kohm, but I want to try a double gate
mosfet to be able to remove the drain resistance which increases the
drain current noise.
If I use a double gate mosfet, I can obtain the desired drain current
by biasing the first gate and applying the signal to the second one.
The problem is that I need very low gate leakage current (to reduce
noise), so the need for a mosfet without gate protection diodes.

This is all. I hope I've clarified the problem
Thanks all :)
MArco
 
Try Calogic.  They make small signal MOSFETs without protection
diodes.

Thanks for the advice,

unfortunately they don't make double gate mosfets. I only found
devices with the external bulk connection but the transconductance was
too low.
Thanks anyway :)
MArco
 
Top