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Power Fet Fet Biasing

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11 Threads found on edaboard.com: Power Fet Fet Biasing
In most applications of high power balanced amplifiers using 2 fetS (or MOSfets) the gates are biased from separate resistors (through RF chokes or high impedance lines). So the idle current could be adjusted separate for each transistor. Your situation is relative low power, so should be (...)
At the drain, no prob. But power MOSfets (at least the older, cheaper generations) want a large Vgs to fully drive down the on-resistance (8V - 12V) and if you are trying to drive a high current at 6V Vgs, you may find the fet is more dissipative than you expect. A "logic level" (...)
From both, because will be an avalanche failure. Initially will be a breakdown followed by temperature degradation. Is a common failure for fets used in switching power supplies.
hi everyone as we know there is different methods for fet power amplifier biasing.according to this page,two major methods are drain pulsing and gate this page,the advantage and disadvantages of both methods mentioned.but what about the ON/OFF ratio?Is it the same in both methods?
BF244 is an n-channel Jfet, so your power supply should be reversed (+ @ drain side). Due to its symmetry, the stage works anyway, however not optimal.
hi there adeel, well a hi power amp no. as the fet's used in LNA's are very low power (well the ones in most satellite LNA's (LNC's) anyway) maybe you are referring to another type ?? BUT, that being said you can make a low power transmitter from a LNA by physically unsoldering the (...)
Hi all, I think this is a basic one. I'm new to ADS. My circuit consists of a fet device+biasing network+matching network. I'm interested to see the power gain (and other S-parameters) for different values of one of the inductors of the network. The desire output would be a plot with several power gain (...)
First of all you need an oscillator of the desired frequency. After this you might have to amplify the biasing signal produced by the oscillator by a darlington and by parallel connected transistors or fet's prior to feeding it to the transformer coil. You must have to mention the desired frequecy and the power requirement (...)
I need bias circuit for Ku band power fet i am using fujitsu FLM 1314 device i can't find any application note for biasing of this device.
Before applying the VD of power fet i bias its vg according to datasheet but when i power up the fet by applying its VD its vg drops and fet take less current without any RF signal at input. pls can anybody explain why vg drops ?
By DC tracing, you can get the Vds for your amplifier. You can trace the V-I curve using either simulator or some GRIB controlled power subpply. Vgs is determined by class of operation of the amplifeir and/or maximum Ids.