BF862 or other low noise JFET

[tomaszsztejka]

Hi,

  At the end of 2017 the BF862 JFET transistor got end-of-life. Currently, as far as I can find, the entire BF86x family has a "not recommended for new design" status. The BF862 was one of the lowest noise JFET's available and practically almost the world-wide best choice for charge amplifiers in nuclear applications.

Since I'm using it extensively in many applications of such kind I would like to know what replacement do You recommend? It doesn't have to be NXP part though.

 The replacement criteria are:

 - industrial temperature range;

 - lowest possible noise;

 - low current at this noise;

 - negligible input leakage;

 - high bandwidth;

 - low cut-off voltage.

Best regards,

 Tomasz Sztejka.

[hxy]

Hi, have you found a suitable replacement? I had similar difficulties and I hope to get your help

[catraeus]

Redesign will be needed, but InterFET, Central Semi and Linear Systems all provide extraordinarily low noise parts.

[jarred]

I would like to voice the same disappointment you have that the BF86x series has been made obsolete with no suitable replacement available. It would be nice if NXP would make a recommendation for a suitable replacement rather than dismiss this problem. 

My lab uses the BF862 JFET in most of our analog frontends for various instrumentation devices. For some time last year we were searching for a suitable replacement and could not find anything quite the same. I believe for a time, Digikey was recommending some other JFET in SOT-23 packaging which was not anywhere near comparable. We do not yet have a solution to the need for a replacement for this part. If we come up with anything, I will share with you here.

[guoweisun]

Thanks for your interesting in NXP products.

These kind of devices almost EOL now,so I am afraid that we don't have replace part.

Hope you can understand!