Here is my latest final Choctaw.
It has lower distortion and is what you should build.
It has lower distortion and is what you should build.
I suspect with these you cannot stabilise the bias currentIRFP240 and IRFP9240
Hi, just read few posts before. It is possible with additional effort of thermal tracking bias, it was explained, but not subject of this thread....Is it possible to use IRFP240 and IRFP9240 instead of ECX10N20 and ECX10P20?
should we make a new thread for that?@lineup
Can you tell us the important characteristics to respect for the OPA? I don't have a 1655 in stock but I have a whole bunch of other references, hence my question.
could i use a simpler op amp such us ne5534?
I do not recommend NE5534 or IRFP240.Is it possible to use IRFP240 and IRFP9240 instead of ECX10N20 and ECX10P20?
Because they will have less than 10 Watt output.
Maybe only 5-6 Watt.
However there are several opamps that can be used.
They should preferably be RRO, rail to rail output. And unity gain stable.
Probably OPA134 (OPA2134) can be used.
you have to work with a VBE multiplier because the Vgs at EXC starts at 1V and you get 1Amps drain current. IRFP240 need about 2-4V VGS to be in the linear area to get about 500 mA.Is it possible to use IRFP240 and IRFP9240 instead of ECX10N20 and ECX10P20?
so you have to "set" the VGS higher and must keep that stable because Vertical MOSFET´s are negative tempco !!--> thermal runaway!!!
look at the datasheets at the input characteristics.
EXC...
IRFP240
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what are some cheap latfet options?I have simulated it with the OPA134. Distortion shown in post 330. Loopgain margin almost 90°. Temperature stability seems very good. It should be a simple project even for beginners, however good to make a functional sample to verify the simulation.
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no such thing as "cheap" latfets ...what are some cheap latfet options?
unless you have friends that gift you some ...
really?no such thing as "cheap" latfets ...
unless you have friends that gift you some ...
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