Yes I have tesed it, I've compared the sound of the 9240 from IR with an 9240 from vishay. There are big difference, the 9240 from vishay is more softer and sound much better.
I want to know if someone have compared the 240/9240 to FQA19N20/FQA12P20 ?
lalaina
RS components
Vishay | Semiconductors | Discretes | MOSFET | MOSFETs & JFETs - P-Channel |IRFP9240PBF
If you buy 100, the price is reasonable. I will go halves if you are interested.
Vishay | Semiconductors | Discretes | MOSFET | MOSFETs & JFETs - P-Channel |IRFP9240PBF
If you buy 100, the price is reasonable. I will go halves if you are interested.
Thanks
At Mouser if you look at the data of the mosfet it is produced by IR .
I can find that in Toronto , and no shipping charge . But I do not want that.
I have some (12 pair)Toshiba 2SK1529 & 2SJ200 at hand but I think I can't use them to replace the IRFP240 or IRFP9240 .
Probably I order from Tech DIY FQA12P20 to replace the the IRFP9240 .
IRFP240 I have at home .
When I ordered for my Aleph2 I took 75PC .
I will see , at first I want to test the A2 if I already have everything for that .
Of course I will each the PC board for the F5 and I'll buy the resistors , any way I have make a order from PartsConnexion I need some resistors and caps for another DIY project .
Right now I just do not want to buy 50PC IRFP9240 . If I like the sound of the A2 I would like to keep it .
I had a A30 and it was close to my taste .
I think about these because your test result it look so nice and these amp so simple with good coponets it is almost impossible not to get a nice sound .
Greets
At Mouser if you look at the data of the mosfet it is produced by IR .
I can find that in Toronto , and no shipping charge . But I do not want that.
I have some (12 pair)Toshiba 2SK1529 & 2SJ200 at hand but I think I can't use them to replace the IRFP240 or IRFP9240 .
Probably I order from Tech DIY FQA12P20 to replace the the IRFP9240 .
IRFP240 I have at home .
When I ordered for my Aleph2 I took 75PC .
I will see , at first I want to test the A2 if I already have everything for that .
Of course I will each the PC board for the F5 and I'll buy the resistors , any way I have make a order from PartsConnexion I need some resistors and caps for another DIY project .
Right now I just do not want to buy 50PC IRFP9240 . If I like the sound of the A2 I would like to keep it .
I had a A30 and it was close to my taste .
I think about these because your test result it look so nice and these amp so simple with good coponets it is almost impossible not to get a nice sound .
Greets
Same here ... How did you manage to get them to fit? The leads on mine are too fat to make it through the PCB and too short to mount vertically. I might just end up using the scrap leads from my other resistors and soldering some 'extensions' onto the dales.
Thank for the advise .
I'm not 100% sure if I can use them with good result , I would be curious about the Master opinion .
I purchased them as a lateral mosfet ($15CAD /ea) because Lineup wrote these are laterals .
After I purchased them now I can't use them . It would be great if I could use it here .
Otherwise just I have them , I can't return it to the store .
Greets
I'm not 100% sure if I can use them with good result , I would be curious about the Master opinion .
I purchased them as a lateral mosfet ($15CAD /ea) because Lineup wrote these are laterals .
After I purchased them now I can't use them . It would be great if I could use it here .
Otherwise just I have them , I can't return it to the store .
Greets
gaborbela,
2SK1529 & 2SJ200 are great output devices for F5 - using them is an improvement.
Your schematic with 2sk135/2sj50 (2SK1058/2SJ162) as cascodes to input JFETs is a waste of good parts - cascode devices make no contribution of their own, you'll be fine with some nice BJTs, like BC550/BC560 or similar.
The other thing is that your idea won't work as drawn in you sch.- 2sk135/2sj50 (2SK1058/2SJ162) lateral MOSFETs are Enhanced mode devices, they are not self biased like JFETs.
This is a possible way to cascode input JFETs:
2SK1529 & 2SJ200 are great output devices for F5 - using them is an improvement.
Your schematic with 2sk135/2sj50 (2SK1058/2SJ162) as cascodes to input JFETs is a waste of good parts - cascode devices make no contribution of their own, you'll be fine with some nice BJTs, like BC550/BC560 or similar.
The other thing is that your idea won't work as drawn in you sch.- 2sk135/2sj50 (2SK1058/2SJ162) lateral MOSFETs are Enhanced mode devices, they are not self biased like JFETs.
This is a possible way to cascode input JFETs:
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Hello Juma
First of all thanks for your help !
I want to be clear do the laterals work how the schematic was drawn & simulated by thanh1973 or not ?
These is not a question about the (value of laterals) , I just want to be sure when I put the amp together it will work 100% !!!
I already design the PC board layout with the 2SK1058 & 2SJ162 Hitachi laterals after how the schematic was drawn by thanh1973 .
Now I will wait , I do not each the PC board until these cascode mode is not clear totally!
I also have Hitachi 2SK214 & 2SJ77 driver (lateral) , if those are OK I can use them . I prefer laterals for cascoding if there is any advantage ,I like the soft sound of the lateral mosfet . I do have 5-6pair at hand .
Do I need the 22uF capacitors with the 4.7K resistors ?
Now a bit not clear all to me .
Also thanh1973 you wrote probably the cascode devise it will be to hot ?? If I use that small BJT or the smaller laterals do those handle the heat?
I'm sorry but now I get confused .
Please someone help me with these questions !!!
If is possible I would like to use the Hitachi 2SK214 & 2SJ74 for cascode .
Can you help me with these or I must use BJT.
Thanks for the help .
I will not rush to each the PC boards until I'm not sure everything done the right way .
Greets
First of all thanks for your help !
I want to be clear do the laterals work how the schematic was drawn & simulated by thanh1973 or not ?
These is not a question about the (value of laterals) , I just want to be sure when I put the amp together it will work 100% !!!
I already design the PC board layout with the 2SK1058 & 2SJ162 Hitachi laterals after how the schematic was drawn by thanh1973 .
Now I will wait , I do not each the PC board until these cascode mode is not clear totally!
I also have Hitachi 2SK214 & 2SJ77 driver (lateral) , if those are OK I can use them . I prefer laterals for cascoding if there is any advantage ,I like the soft sound of the lateral mosfet . I do have 5-6pair at hand .
Do I need the 22uF capacitors with the 4.7K resistors ?
Now a bit not clear all to me .
Also thanh1973 you wrote probably the cascode devise it will be to hot ?? If I use that small BJT or the smaller laterals do those handle the heat?
I'm sorry but now I get confused .
Please someone help me with these questions !!!
If is possible I would like to use the Hitachi 2SK214 & 2SJ74 for cascode .
Can you help me with these or I must use BJT.
Thanks for the help .
I will not rush to each the PC boards until I'm not sure everything done the right way .
Greets
No you don't have to use bipolars.
Since you already have the laterals I would use them.
Maybe try it point to point first just to confirm if it will or won't work, the way it is drawn in the schematic.
Juma could be right, that it won't work the way it has been drawn. However the simulations say otherwise.
Do one channel point to point and if it doesn't work we will make the necessary changes to get it to work.
With 40 Volt rails you have around 300mW to 400mW going through the cascode device.
If I had some lateral mosfets I would do it for you.
Since you already have the laterals I would use them.
Maybe try it point to point first just to confirm if it will or won't work, the way it is drawn in the schematic.
Juma could be right, that it won't work the way it has been drawn. However the simulations say otherwise.
Do one channel point to point and if it doesn't work we will make the necessary changes to get it to work.
With 40 Volt rails you have around 300mW to 400mW going through the cascode device.
If I had some lateral mosfets I would do it for you.
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why such a high power FET for the cascode?
the cascode device passes the jFET current and drops ~half Vsupply(+0.6Vbe-Vgs of output). The dissipation ~100mW to 150mW, for 5 to 7mA of jFET bias.
the 1kVA transformer has a DC rating of 8.3Adc continuous.
It can supply ~2A bias per channel for a two channel amplifier. OK for a standard two channel F5 but not for a pair of 2.4A bias F5s.
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We have here following issues:
- word "Lateral" (as in "Lateral MOSFET") describes construction type associated with negative temp. coef., but it's stil enhancement mode device (meaning that k135 needs gate more positively polarized than source in order to conduct)
- cascodes are used to extend voltage range where certain device is used. Welcome byproduct of cascoding is some linearization of that stage. Type of cascoding devices (jfet, bjt, mosfet) doesn't play a significant role by its' self. Every type demands specific implementation (there is no "one size fits all" solution).
- In case of F5 input stage small BJTs (TO-92) are quite appropriate since current through each JFET is usually 5-8mA (depending on JFET type and grade) which results in 100-160 mW of dissipation and that's OK for 625mW rated devices.
Don't expect much from spoon-feeding, try to learn more on the subject, this forum is full of links to great articles. Spend more time searching and reading and you'll be less confused in the future
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!!!!
best way to retain information is "hands on" for some learners. I will agree that point.
But the experimenters need guidance, otherwise the risk is run of nothing being learned and confusion results with either no useful conclusions or completely wrong conclusions.
By definition an expert knows his/her field. They can never be wrong, unless they deliberately try to mislead.