Output stage assembled and tested. Everything works perfectly.
Next up will be to solder it all up on protoboard and play some music through it.
Congrats! Half of the amp is living...... 😀😀😀
yes we are beasty and crazy but until now only three, let us make F4 friends, come in.....!
😀😀😀😀
😀😀😀😀
Here are some IXFN44N80Q3 capacitance measurements. They agree fairly well with the datasheets:
Attachments
Last edited:
You want measurements? I give you measurements:
The columns are Capacitance, Vds
IXFN44N80Q3_Crss_500kHz_Vin1V_100R_3:
matrix(
[2639.643, 0.100],
[2092.511, 1.741],
[1660.747, 4.010],
[1452.482, 5.639],
[1261.769, 6.273],
[832.730, 6.587],
[465.920, 6.884],
[152.764, 7.323],
[78.104, 7.801],
[58.946, 10.738],
[48.607, 13.373],
[45.566, 16.416],
[38.661, 21.603],
[33.452, 25.637],
[30.854, 31.297])$
IXFN44N80Q3_Ciss_100kHz_Vin500mV_100R:
matrix(
[30660.732, 0.100],
[28124.641, 1.907],
[25384.206, 3.827],
[21513.361, 6.430],
[18652.306, 8.868],
[18676.345, 11.821],
[18326.933, 13.792],
[17984.509, 16.979],
[18344.200, 20.814],
[17984.509, 23.962],
[18344.200, 27.260],
[18344.200, 31.301])$
IXFN44N80Q3_Coss_100kHz_Vin500mV_100R:
matrix(
[34911.407, 0.620],
[22577.794, 2.503],
[17806.444, 4.150],
[13775.596, 6.011],
[10298.261, 6.429],
[8063.850, 6.572],
[4484.476, 6.769],
[2402.339, 7.037],
[1911.000, 8.833],
[1507.201, 12.013],
[1283.067, 15.274],
[1107.870, 19.707],
[993.041, 23.905],
[879.751, 29.626],
[865.696, 31.295])$
Congratulations generg!
There are quite a few of us that are following this thread with interest but are sitting on the fence until one of you guys manages to tame these hockey pucks. So for my understanding of this amp you are using high transconductance devices IXFN48N60P and IXTN40P50P as you mention in post#270 and the circuit is as in post #254?
The reason you are transcoding the buffer fet pair is to be able to drive M1 and M5 which in turn will be the driver for the high input capacitance of the hockey pucks?
Then to prevent thermal runaway you use the TL431 which we see bolted in the middle of the two hockey pucks? Then you have R17 sense as the positive feed back?
If I have understood this correctly you have made a wonderful sounding amp with about just over 2 Amp bias and 0 mV offset what is the frequency response like can you post pictures of what say a 50KHz square wave looks like please. Again many thanks for sharing your efforts and patience.
I'm also looking forward to see what 2 picodumbs has accomplished keep it coming!
There are quite a few of us that are following this thread with interest but are sitting on the fence until one of you guys manages to tame these hockey pucks. So for my understanding of this amp you are using high transconductance devices IXFN48N60P and IXTN40P50P as you mention in post#270 and the circuit is as in post #254?
The reason you are transcoding the buffer fet pair is to be able to drive M1 and M5 which in turn will be the driver for the high input capacitance of the hockey pucks?
Then to prevent thermal runaway you use the TL431 which we see bolted in the middle of the two hockey pucks? Then you have R17 sense as the positive feed back?
If I have understood this correctly you have made a wonderful sounding amp with about just over 2 Amp bias and 0 mV offset what is the frequency response like can you post pictures of what say a 50KHz square wave looks like please. Again many thanks for sharing your efforts and patience.
I'm also looking forward to see what 2 picodumbs has accomplished keep it coming!
Let me guess..... A beasty F25 Frontend and even bias board.....🙂)
So I am eager to hear about your progress and sound impression!
THX formantjim for the comment!
The taming is as Picodumbs said no more the problem, more the adjustement of distortion and a reliable comparison to another very good amp.
You know selfmade amps switched on blow away every amp of this world......one day, until you get sober......:--))
The taming is as Picodumbs said no more the problem, more the adjustement of distortion and a reliable comparison to another very good amp.
You know selfmade amps switched on blow away every amp of this world......one day, until you get sober......:--))
I am so happy that you fill the gap between believing in the PDF data and reality!
THX!
One Successful Cat Skin
If you want to build something, this one has been tested to death and works perfectly. There are certainly other ways to do it that will also work.
If you want to build something, this one has been tested to death and works perfectly. There are certainly other ways to do it that will also work.