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previous: Jack The 9v power is your problem. Crank... -- 10/26/1999 11:12 PM

Re: FET Electrical Performance

10/27/1999 2:19 PM
R.G.	Re: FET Electrical Performance Supply voltage and Gm do interact in that you need a higher voltage for high Vgs/low Gm devices to get a higher current level. JFETs are usually square-law devices, so the incremental Gm increases with increasing drain current. However, the Vgs of the JFET has and the transconductance have an even bigger effect. Low Vgs JFETs tend to be high-Gm devices as well. A 2N5384 or 2N5385 should be a big improvement. 2N5457's have Vgsoff of about 4-7 volts usually.

10/27/1999 2:19 PM

R.G.

Re: FET Electrical Performance

Supply voltage and Gm do interact in that you need a higher voltage for high Vgs/low Gm devices to get a higher current level. JFETs are usually square-law devices, so the incremental Gm increases with increasing drain current.

However, the Vgs of the JFET has and the transconductance have an even bigger effect. Low Vgs JFETs tend to be high-Gm devices as well. A 2N5384 or 2N5385 should be a big improvement. 2N5457's have Vgsoff of about 4-7 volts usually.

Replies:

Scott RGDid you mean 2N54... -- 10/27/1999 5:35 PM