It is hard to search for good Audio Mosfets-may be because of my lack of experience or knowledge😉
I am looking for better mosfet sub on rail voltage of +- 80v amp.
Thank you in advance
I am looking for better mosfet sub on rail voltage of +- 80v amp.
Thank you in advance
J162/K1058 can't properly handle 80Vdc rails.
If you prefer to stick to Lateral MOSFETs you're better off with Exicon ECX10N20/ECX10P20, TO247 package equivalents of the 200V Hitachi J56/K176.
Can be ordered direct from Profusion in the UK.
If you prefer to stick to Lateral MOSFETs you're better off with Exicon ECX10N20/ECX10P20, TO247 package equivalents of the 200V Hitachi J56/K176.
Can be ordered direct from Profusion in the UK.
these are almost the same devices as the 2SJ162/2SK1058,
the only difference is current drain increased from 7 to 8 A ,
and a slight increase of 20 V VDS for the 2220/351 parts,
and 40V for the 2221/352...
Dear Jacco,
Would you kindly tell me why the K1058/J162 can't handle 80V? The datasheet says max 160V. I have 8 pairs of these and therefore it would be good to know the safe max. voltage. Thanks!
wahab,
the 2SK2220/2SJ351 is a more closely matched pair due to improvement of the P-channel device. Look at the value of Crss.
the 2SK2220/2SJ351 is a more closely matched pair due to improvement of the P-channel device. Look at the value of Crss.
well, all the other parasistic parameters , Ciss and Coss are no better, and even worse
on the 2220/351....all in all, i would stick with the 162/1058 if ever they are cheaper..
myself i use the now obsolete TO3 variant of these devices, and i can tell you,
they are very rugged and very good sounding..
on the 2220/351....all in all, i would stick with the 162/1058 if ever they are cheaper..
myself i use the now obsolete TO3 variant of these devices, and i can tell you,
they are very rugged and very good sounding..
Basic power supply reason, the rail voltages will fluctuate due to variations in the mains plus transformer regulation.
Hong Kong mains power is 220Vac with +/-10% bandwidth, so mains voltage can range between 198Vac and 242Vac.
Common regulation numbers for toroidal transformers are 4.5% for a 500VA, 4% for a 750VA, 3.5% for a 1000VA.
On fast transients, output voltage can be close to rail voltage with the opposite output device opened, Vds close to 2*Vrail.
J162/K1058 can handle a max Vds of 160Vdc, so rail voltage level should not go above 80V.
Using a 500VA in Hong Kong boils down to nominal rail voltages of +/-70Vdc.
(70 + 14.5% makes 80)
this should go into some fixed information resource.
So many beginners and many who should know better forget about using a little arithmetic to check that their design will stay in specification for mains voltage and transformer voltage variations.
As a practical example, I live in Buenos Aires, where power line distribution is star connected 3x380V so the very same line feeds homes with 220V (phase to neutral) and industries (or "big spenders" such as elevators or building size Air Conditioning) with 3x380V (phase to phase).
The phase to phase voltage is guaranteed and very stable, but each 220V line not that much, because it depends on load being evenly split among phase wires , which often is not.
Just today I measured: 198V/209V/226V so you can see that even at the same time of the day, plugging the same amplifier in different homes, in the same street, can yield quite different actual rail voltages.
So working with a reasonable safety margin, as suggested above, is a must.
The phase to phase voltage is guaranteed and very stable, but each 220V line not that much, because it depends on load being evenly split among phase wires , which often is not.
Just today I measured: 198V/209V/226V so you can see that even at the same time of the day, plugging the same amplifier in different homes, in the same street, can yield quite different actual rail voltages.
So working with a reasonable safety margin, as suggested above, is a must.
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