Inquiries about EXT_CAP of AD5271


For circuit reasons, we are using the AD5271 with a voltage of Vdd:3.300V and Vss:-1.720V.

We are using only RAM because writing to ROM does not work well, probably due to Vss.

I am using RAM only.

So, please tell me about the following.

・ If the EXT_CAP pin is not used, what potential should it be fixed at?

If it is used for a charge pump, I think OPEN is better, but what do you think?

Best Regards,


Parents Reply
  • Hi vsethia,
    Thanks for your answer.
    I was wondering if it would be better not to connect it since the customer is using a lower than normal Vss value.
    Anyway, the customer will not use the ROM.
    If there is no problem, I will ask them to connect it as it is.
    I think we're talking internal circuitry here.
    If you don't seem to be able to answer, I will tell the customer that.

    Best Regards,