Yeah, this idea was in the back of my head too..... I am afraid it will stay there,
I am not skilled enough to implement it.
Zen Mod what do you mean bei "OS" and "OP" is an opamp?
I am not skilled enough to implement it.
Zen Mod what do you mean bei "OS" and "OP" is an opamp?
which else than working temp - say 60C on heatsink near to part
what I meant - instead of TL431 and NTC gadget , one can introduce 0R1 in appropriate rail ( thus most probably equalizing difference in Rdson between two sexes) and going to set Iq trough appropriate measuring of voltage drop across mentioned 0R1
that way , OS could be placed on much broader range of heatsinks ( count on normal Greedy Boyz behavior)
so , 0R1 , OP , one precision zenner , few resistors and one optocoupler , that's all needed for flawless bias operation
I believe that idea is recently covered around (lhquam ?) , but I didn't follow it thoroughly , just because it was in context of M2 , and I wasn't interested in bettering it
most probably still not interested in bettering M2
hey - but it's wakoo idea - input buffer , autoformer - interstage buffer - puck follower
mini F5T/BA3FE tweaked as FE ..... sorta boring ....... for me - exact biasing scheme Pa is using here , is that jewel worth looking for , in XA25
OK , exact pucks combo , too ...... believing that he did his own homework thoroughly , as always is the case ..........
Generg
Do you recall if this was the model we previously tested or is it different?
I will look at this one now.
I really love this idea but I won't be implementing it here, as it goes against the whole design philosophy of this amp to address a problem that doesn't exist.
Sought of like making an ultra raw, light weight, racing car, then adding a computer which weighs 500kg so that noobs can drive it without crashing.
You've gone 1 step sideways, not even forwards, (addition of unneeded control) then at least 1 step backwards (addition of some degeneration).
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Great work Rob.
I still need to check curves for accuracy, but before that, I'm still getting weird results with the IXYS 40P50P model.
No spice errors, just spitting out a weird curve, more like a step. Hahaha
Could you describe some of the things you are doing to make it operate.
I still need to check curves for accuracy, but before that, I'm still getting weird results with the IXYS 40P50P model.
No spice errors, just spitting out a weird curve, more like a step. Hahaha
Could you describe some of the things you are doing to make it operate.
The curve looks completely wrong but to confirm it can you run between -4.5V to -5.0V and please add grid to graph.
Yeah curve is wrong.
It's measuring around 11.7S instead of around 6.5S at our operating point.
The model needs to be modified.
I already have models that match our devices but they are based on simple model parameters but the important curves do match the part.
Keantoken can do more accurate models than me, but it usually doesn't change the results significantly.
It's measuring around 11.7S instead of around 6.5S at our operating point.
The model needs to be modified.
I already have models that match our devices but they are based on simple model parameters but the important curves do match the part.
Keantoken can do more accurate models than me, but it usually doesn't change the results significantly.
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The error that I got for IXFN44N100Q3 was not from the model it was from my ltspice circuit. the model works fine and now so does the circuit. Ixys has the wrong pspice model for the IXFN44N80Q3 but the data sheet for part number IXFK44N80Q3 looks the same as the IXFN44N80Q3 and here is the graph for it.
Attachments
Nice work Rob.
I haven't bothered checking the N Channel models as I am using 48N60P and I have made my own model which matches the curves I have measured for the devices.
I haven't bothered checking the N Channel models as I am using 48N60P and I have made my own model which matches the curves I have measured for the devices.
I am adding one more feature to this circuit.
1) Add toggle switch across R1 (not seen on circuit)
When R1 is shorted out, it will turn off output stage (stand-by/low power mode) but not the front end circuit.
I could have it so output stage turns completely off or add resistor in series with the switch so that output stage is drawing say 100mA. I'll decide later.
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