while hunting for better parts for x-ccs-bosoz i found this:
http://www.semisouth.com/products/uploads/DS_SJEP170R550_rev1.3.pdf
seems to be a newer, lower power version of their jfets
capacitance is about the same as irf610 - but hey, its a jfet
despite the difficulties of getting hands on them - shouldn't one expect some excitement?
regards
http://www.semisouth.com/products/uploads/DS_SJEP170R550_rev1.3.pdf
seems to be a newer, lower power version of their jfets
capacitance is about the same as irf610 - but hey, its a jfet
despite the difficulties of getting hands on them - shouldn't one expect some excitement?
regards
The new part look fascinating!
The Ciss of the new 1700V part looks much lower than old 1200V part at VDS of our interest.
Trying too read Ciss at roughly VDS=10V (a little hard due to scale of graph) shows that the new part is about 200pF, while even the smallest old part SJEP120R125 shows like 700pF.
Another thing is the ID vs VGS curve, the new part very linear from ID=3A onwards, while the old part SJEP120R125 needs 10A to be so.
The only disadvantage is RthJC thermal resistance, old part 1.1°C/W while new part 2.6°C/W. But the ratio is still smaller than 10A to 3A.
The larger thermal resistance with smaller Ciss seems to suggest that this part uses less wafer area, so hope that it is cheaper.
Anyone making a GB?
The Ciss of the new 1700V part looks much lower than old 1200V part at VDS of our interest.
Trying too read Ciss at roughly VDS=10V (a little hard due to scale of graph) shows that the new part is about 200pF, while even the smallest old part SJEP120R125 shows like 700pF.
Another thing is the ID vs VGS curve, the new part very linear from ID=3A onwards, while the old part SJEP120R125 needs 10A to be so.
The only disadvantage is RthJC thermal resistance, old part 1.1°C/W while new part 2.6°C/W. But the ratio is still smaller than 10A to 3A.
The larger thermal resistance with smaller Ciss seems to suggest that this part uses less wafer area, so hope that it is cheaper.
Anyone making a GB?
while hunting for better parts for x-ccs-bosoz i found this:
http://www.semisouth.com/products/uploads/DS_SJEP170R550_rev1.3.pdf
seems to be a newer, lower power version of their jfets
capacitance is about the same as irf610 - but hey, its a jfet
despite the difficulties of getting hands on them - shouldn't one expect some excitement?
regards
BTW, thanks for the info!
I wrote to them asking about the price.
Hopefully they will entertain our small need and give a reasonable price.
It looks like a nice part. I'll have to get some.
If you are buying, can I piggyback on you and get a few hundreds together?
Looking at the datasheet, do you think the gate current comes in a little too early? (at 175c, there is noticeable gate current from VGS=2.0V, which correlate to ID=2.2A@125C or 1.8A@175C only) If I did not get it wrongly, if we want this part to have peak ID>3A per device or so, we will need to supply IG in the range of tens of mA. Since we are likely to parallel a few of these to get sufficient power dissipation and transconductance, the front end will need to be capable of delivering 100mA or so. If we keep maximum ID per device below 1.5A, this gate current will be gone though.
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I have ordered some (few hundred) SJEP170R550 from semisouth, other than just the old SJEP120R100.
The leadtime is quoted to be 2-3 weeks.
Nelson,
In case that Semisouth charge $60/piece instead of giving free samples to ex-customers, may I have the honor to contribute a few pieces of these to you as an appreciation of your generosity?
The leadtime is quoted to be 2-3 weeks.
It looks like a nice part. I'll have to get some.
Nelson,
In case that Semisouth charge $60/piece instead of giving free samples to ex-customers, may I have the honor to contribute a few pieces of these to you as an appreciation of your generosity?
I think so too. Even Papa get interested.
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The 2 to 3 week lead time, is highly optimistic
It's been more than 3 weeks since I placed an order, and I sure have not seen any sign of them yet.
It though varies how long lead time they quote.....One could suspect they throw a dice when asked, and convert the number of eyes to weeks
Anyhow, could be fun to see what they can do soon.
Magura
It's been more than 3 weeks since I placed an order, and I sure have not seen any sign of them yet.
It though varies how long lead time they quote.....One could suspect they throw a dice when asked, and convert the number of eyes to weeks
Anyhow, could be fun to see what they can do soon.
Magura
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