this part on Ganglion is overheating, what is it?

CloudCloud iran
edited March 2021 in Ganglion

Hello Everyone
Some years ago in a seminar I answered a question and they gave me a ganglion board , but unfortunatelly it was not working :D

I told my friend to repait it and he said buy this part (which is marked on the photo) , the problem is from there (it gets too hot and the power light is on but so weak). Is there anyone can help me by the name and in case tell me where I can buy in Europe?

many thanks in advance.


  • wjcroftwjcroft Mount Shasta, CA

    Cloud, hi.

    If you look carefully on your board, the part circled is U10, your red line obscures this label.

    If you examine the schematic in the upper right corner, you can see that U10 is an NCP300 voltage detector chip,

    The function of this, I believe, is to validate the proper battery voltage level is reached, then to 'enable the two voltage regulator chips above this in the diagram, via the V_ENABLE signal. This then turns on the regulated power supply voltages Vdd and Vaa.

    My suggestion is that you check ALL THREE of these power supply chips. It's possible that one of the other chips is interacting with U10 somehow and causing the overheat / malfunction. The NCP300 should be available from any parts distributor in your area. Similarly for the NCP551's.

    Regards, William

  • @wjcroft many thanks to your answer it was a big help as I don't know anything about those maps. I checked the website and I found several models pf NCP300 to buy which divided by the voltage from 0.9 volts to 4.7 volts which one is the right one if you know it?


  • wjcroftwjcroft Mount Shasta, CA

    The Ganglion is designed to operate at standard 3.3V logic levels. So most likely the 3.0 V version is what you want. The other values on either side of that are:

    • 4.5 V which is too high
    • 2.8 V which may be too low

    AGAIN, I stress that you should check (with a digital voltage meter), all the chip components in the power supply section of the board. It may be that the voltage regulators (U9 and U11) are the source of the problem / overheat. U10 is only supposed to DETECT a valid voltage level. So seems odd that this would be the overheating component. More generally it is the regulators which fail.

  • wjcroftwjcroft Mount Shasta, CA

    Note that in addition to the voltage level, there are also variants that produce the RESET output of the chip as logic high or logic low. Hmm, please have your tech study the data sheets carefully to determine which you want. Just on first glance, it appears that V_ENABLE is logic high, but I may be wrong.

  • Dear William @wjcroft.
    Your consern makes sense, I will buy both models to make sure I wont order again and wait
    NCP551 is 3.3 volt like the NCP300 or the voltage is different?
    Thank you again for your information. Once might you remember I asked some questions about Muse application and you helped me kindly.

  • wjcroftwjcroft Mount Shasta, CA

    Masoud, hi.

    Data sheet for NCP551 is here,

    The Vdd supply should be 3.3V. I'm not sure about Vaa supply. Examine the schematic carefully.

    The NCP300 is likely set at 3.0V, there is not a 3.3V version of that part. See previous comment, nearby values are 4.5V (too high) and 2.8V (likely too low.)


  • wjcroftwjcroft Mount Shasta, CA

    @Cloud, hi.

    OK, should have done this before: I just did actual measurements on a working Ganglion.

    BOTH Vdd and Vaa are 3.0V, that means ALL THREE of the NCP components (NCP300, and 2 x NCP551), are all the 3V version. Measured battery voltage was 3.7V. The NCP300 part, pin 1, 'RESET' or 'V_ENABLE', is logic high = true. What I measured on pin 1 was the same as the battery voltage, 3.7V. That is because the actual voltage regulation down to 3V, only happens after the NCP551.

    Regards, William

  • @wjcroft many thanks again,
    Yesterday night I wanted to buy, I selected them but I said tomorrow I finish the purches. I change the NCP551 because I chose the 3.3 v.
    I need this to try brain-trainer method as I have the bio-era dongle. Hope it is worthy.
    Many thanks again William hope I can compensate for you

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