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AMC1301-Q1: VDD1 supplied with 3.3V against recommend 5V

Part Number: AMC1301-Q1
Other Parts Discussed in Thread: SN6501, AMC1301EVM, AMC1301

Hi All,

Datasheet recommends 5V for VDD1 though the range is from 3 to 5.5V

I would like to know whether VDD1 and 2 can be given 3.3V from the same source or not. Appreciate your assistance.

  • Hi Santhosh!

    Welcome to our e2e Forum!  Great question here on the power supplies for the AMC1301-Q1!  You certainly can supply power to the AMC1301 from the same source, the only issue there is that you may be defeating the isolation capability of the device.  If you need to maintain the isolation, you could use a device like the SN6501 with a small signal transformer to generate an isolated 3.3 - 5V source for VDD1 from your VDD2 supply.  That approach was used on the AMC1301EVM if you'd care to take a loot at the implementation.

  • Hi Tom,

    Appreciate your assistance. Actually, the idea was to use two different LDO for providing 3.3V volts. I wanted to know whether the performance deteriorate if given 3.3V instead of recommended 5V. Of course, I will isolate the supplies but for logistics it was comfortable to generate an extra 3.3V but we can certainly use either the isolation(transformer) or separate supply of 5V from the sensing voltage.
  • Hi Santhosh,

    If you look over the AMC1301-Q1 Electrical Characteristics Table beginning on page 7, you can see the note regarding the test conditions which show VDD1 being swept from 3.0 to 5.5V - the only real difference there is with power consumption. Other plots, beginning with section 6.11 show performance at 3 and 5 V.
  • I see that the performance of the 3.3V is better than 5V in terms of %deviation peal/maxima. May I know as to why it is recommended to go for 5V? Am I missing something here?
  • Hi Santhosh,

    On page 4 of the AMC1301-Q1 datasheet, the Recommended Operating Conditions table (Section 6.3) shows 3.0 to 5.5 V for VDD1. If you are referring to the NOM 5.0 V entry in that table, this would be related to similar devices in the market which don't have the same operating VDD1 voltage range.