(and) low noise Power MOSFET

[sonidos]

TPS7Axxxx
This fet look like interesting replacement for bf862.
I got 50 bf862 from eBay . They turned out to be fake one.

Looks like a vendor on AliExpress can't be trusted. I just received 100 jfets that are supposed to be marked 2aw per their description, but are marked W28U. I put one on the curve tracer and it is no good. This makes 2 different suppliers from China who sold me alternate parts.

 

[sonidos]

Here's a fuzzy shot of the jfets that I received tonight. Hopefully the image can be brought up full size.

 

[Dibya]

Looks like a vendor on AliExpress can't be trusted. I just received 100 jfets that are supposed to be marked 2aw per their description, but are marked W28U. I put one on the curve tracer and it is no good. This makes 2 different suppliers from China who sold me alternate parts.

Join me . I got scammed too.
I have to a find a proper source for bf862.

 

[xrk971]

Looks like a vendor on AliExpress can't be trusted. I just received 100 jfets that are supposed to be marked 2aw per their description, but are marked W28U. I put one on the curve tracer and it is no good. This makes 2 different suppliers from China who sold me alternate parts.

File a complaint and you will be refunded. Ali is good about that. Provide photo showing incorrect markings.

Codebook shows W28 as BFP280 - an NPN BJT. Not even close to a JFET.

 

[PRR]

Any one can help me to setup LTSpice ? Where to start?

Installing and using LTspice IV (now including LTXVII). From beginner to advanced.

 

[Dibya]

Installing and using LTspice IV (now including LTXVII). From beginner to advanced.

Thanks a lot

 

[sonidos]

A bit of an update, Dibya. I found a source in China that shipped me chips marked 2aw. At first I was pretty happy to see that but something was slightly off and I noticed that they were larger than the US purchased BF862s. It was too large to fit in my SOT23-3 testing adapter, so I clipped alligators to each lead and measured on the curve tracer. The one sample appears to be a jfet but the performance was slightly worse than my genuine part. I wonder if xrk noticed a difference in size on the chips he ordered.

 

[Dibya]

A bit of an update, Dibya. I found a source in China that shipped me chips marked 2aw. At first I was pretty happy to see that but something was slightly off and I noticed that they were larger than the US purchased BF862s. It was too large to fit in my SOT23-3 testing adapter, so I clipped alligators to each lead and measured on the curve tracer. The one sample appears to be a jfet but the performance was slightly worse than my genuine part. I wonder if xrk noticed a difference in size on the chips he ordered.

I am sure those slightly bigger one are made by NEXPERIA in HK.

 

[sonidos]

If they are indeed made by Nexperia and are larger, then I would definitely feel better about that. I'll read up some more on these and perform more measuring. I'll post the source if I can verify they're ok.

 

[sonidos]

Ok, I pulled out 2 jfets and I had to position this larger jfet just right to seat properly in the adapter board. I was pretty surprised to see they matched up pretty well.

 

[xrk971]

SOT-23 is a standard and the pins and case need to conform. If they are bigger, it probably is not SOT-23. All the ones I have bought whether from Mouser, Digikey, or Ali, all conform to the same package outline. No noticeable difference.

 

[gerhard]

In a different thread we have concluded that BF862 is definitely EOL, also at Nexperia.

There are some JFETs made by ON semi that can fit the bill.
Some inherited from Sanyo and some really new. Available from DigiKey.

< someSmallSignalJFETs | Gerhard Hoffmann | Flickr >

On the left are 2 *310 that may be useful as cascodes.

regards,
Gerhard

 

[EUVL]

> Some inherited from Sanyo and some really new.

Which news ones are you referring to ?
Isn't NSVJ3910 = CPH3910 (ex Sanyo) ?
And NSVJ3557 = 2SK3557 (ex Sanyo) ?

2SK2394 is certain ex-Sanyo.
J310 has been around for quite a while, from Fairchild, NXP, .... (all companies that do not exist any more).

In the latest article from Dimitri in AX, he measured noise performance of :
CPH3910, 2SK2394, 2SK932, the later LS FETs, plus MMBF5103 and BSR58.
The latter two are pleasant surprises.




Cheers,
Patrick

 

[sonidos]

xrk,

That's disconcerting. I just checked with my digital calipers and the width of the body should be 1.2 mm to 1.4 mm. I measure about 1.6 mm to 1.8 mm wide.

I will just be happy with the authentic ones I have rather than hunting around for unobtainium.