Help me distinguish the IRF244.

[posxia]

My dear DIYer,I bought some IRF244 in the electronic market several days ago, TO-3 package,but I never saw this Mosfet,is true or not, ths.

[Magura]

They look like mine, nice fets.

http://www.datasheetcatalog.org/data.../283511_DS.pdf


Magura

[posxia]

THS Magura , I had the datasheet, but just not affirm it is IRF244 .

[wrenchone]

I've never seen IR parts in that sort of TO-3 package with the "figure 8" slug insert. All mine are in plain steel TO-3s. They may be phony or remarked parts from a second or third rate manufacturer. First off, I'd test the gate-source pins to make sure the things are even mosfets.

[john-china]

this is remaked from second hand of older IR product.

but they are real mosfet which can be used in any PASS amp , also rugged , beacuse i also have some with same lables,
i used them , no problem . sonic quality is still good.

[wrenchone]

If they were really IR product, why would they need re-marking? The only legitimate parts I've seen in those TO-3 packages are parts from vendors like Toshiba and Sanken from back in the '80s.

[john-china]

because some want to buy irf240, anothers want to buy irf140,

so how to satisfy all of them to make higher profit. only one way , sell the mosfet remarked irf240 to one who want irf240, and
sell the mosfet remarked ir140 to one who want irf140.
but their stock has only some older irf450, irf250 ,some kinds of other irf serials.
so they must remark some kinds of IR mosfets to one serials. for example irf240. this make matching mosfet more difficult.

another reason is that some one want to buy new mosfet . remarked mosfet looks like new product.

[posxia]

Thank everyone ,I had read all reply though my poor Enlish,
maybe MR. john-china is right sometimes,but please attention the image I attached , I had tested this fet, the vgs is 5V about when ID = 1a, So ,it is a IR parts sure.but I still cannot confirm is IRF244 or not

[wrenchone]

As far as I know, IR never used the 60-mil pins (large size) on anything smaller than their size 5 die, so the part with the big pins could be a re-marked IRF250 (or IRF150, for that matter). The parts with the "figure 8" inserts are probably re-marked Japanese mosfets and not IR product at all. Will they work in the same application? Try them and see. They may be HV mosfets with a much higher on-resistance, though.

[posxia]

NO,NO,I don't think so, this fet I can almost confirm it is IR parts ,because the vgs is 5V when ID = 1a, not as the HV mosfets which the vgs below 2V usually.