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BUF802RGTEVM: Unpopulated is annoying... but no BOM??

Part Number: BUF802RGTEVM
Other Parts Discussed in Thread: BUF802,


A few things to mention regarding the BUF802 eval board, and another regarding the  BUF802 chip itself.

  • Count me as another end user who thought the this evaluation board came populated.  I ordered the eval boards and  BUF802 devices while still in "preview" status - that is when the actual chip part number was XBUF802IRGTR rather than BUF802 etc.  Maybe things changed between then and the actual delivery.  Having said that... $150 for a bare board?
  • I now need to actually populate my bare boards, and other than the schematic pages in the BUF802RGTEVM User Guide I find no Bill Of Materials.  Of course, I can fake it based on the values listed in the schematic, but it would be nice if either the schematic had more detail of the actual parts used in the design, or - preferably - a full on Bill of Materials was included in the user guide.  I see a variety of footprints in the layout and I believe some are low ESL/ESR capacitors.  I assume that it might be important to stick in an appropriate part there rather than some run of the mill decoupling cap I have lying around the lab.
  • The schematic and layout images in the user guide pages have the appearance of being from Altium (though I am not certain).  My point is that perhaps the Schematic generated once had "hover your mouse over the symbol" embedded data for all those schematic symbols the way Altium does when it outputs a PDF, but that information either was never included or has been stripped out by the time those pages made it into the User Guide.

As for the chip itself question: There are a few places in the BUF802 datasheet where, based on the diagram(s), one might surmise the drain of the input FET is going to a package lead and nothing else.  Elsewhere (see below) the Drain is connected to various other points in the circuit.  For clarification purposes; Is the Drain of the input FET available in any way that is independent of the internal V+ "bus"?

  • Hello Miles,

      Thank you for bringing this issue to our attention. We are looking into correcting this problem as soon as possible. From our end, it seems the issue originated due to a mismatch on preview and release as you have mentioned. 

      We will be sending you a free populated board. Please provide your full name, address for shipment, phone number, and email to

      Looking into the last question regarding the drain connection, and will get back to you shortly. 

    Thank you,

  • Hello Miles , i am the project owner of BUF802 and I sincerely apologize for the trouble you have faced with BUF802 EVM.... We have a stock of populated EVM of BUF802 from which we shall be sending you 1 EVM board as mentioned by Sima and also ensuring the stock gets updated on so in future a problem which you faced shall not be faced by others.

    on your 1st point , the part now has been fully released and will have the orderable part number BUF802IRGTR.. The populated EVM which we shall send you over will have the latest part number on it.

    on your 2nd point , i have asked my team to update the BOM ASAP on the BUF802 EVM product page and it shall be updated soon.  We will also send you the BOM via email in reply to the email you shall be sending to Sima.

    on the 3rd point , we are looking into this , I do agree seeing such feature in the past on schematic PDF , we will try to see if we can incorporate it in the user guide. We will also try to upload separate PDFs with this feature if incase it cannot be incorporated into the User Guide PDF.

    The VS+ is indeed the drain of the JFET of BUF802 however like shown in the functional block diagram below it is connected to other points in BUF802. So to answer your question we don't have an independent tapping point for the JFET Drain .

    Feel free to ask any question you might have in using BUF802 we shall do our best to get all your answers technical or otherwise immediately .

  • Thank you for the further clarification on the points and question I raised.
    I have replied to Sima by email.  I have also noted that we actually bought 2 evaluation units back in November and have included a copy of our TI Store confirmation in that email.  Hopefully we can get 2 populated boards.

    Best Regards,

  • As a note: closing thread since the conversation was taken offline.