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ADA4945-1 MODE Threshold

Category: Hardware
Product Number: ADA4945-1ACPZ-R7

What is the threshold for the MODE pin of the ADA4945-1ACPZ-R7? What mode would you expect it to be in with a supply voltage of 5 V and a voltage of 2.5 V on MODE?

I ask because the EVAL-CN0540-ARDZ 24-Bit Data Acquisition System for IEPE Sensors reference design appears to set MODE to 2.5 V:

It can be overridden by writing a 1 to AD7768-1 GPIO3 (which gets it up to 3.3 V), but the Example program for EVAL-CN0540-ARDZ does not appear to do that automatically as part of initialization or anything.

I don't think FDA_DIS (connected to DISABLE_N) is ambiguous, because the ADA4945-1 Data Sheet documents that the ADA4945-1 is enabled at a minimum voltage of DGND + 1.4.

I had mentioned the wrong Data Sheet
[edited by: CK3 at 4:49 PM (GMT -5) on 1 Dec 2022]
  • Oh, I just noticed the "DNI" on R2 and R4, so MODE and DISABLE_N will be pulled up to 5 V unless the resistors are inserted. The ADA4945-1 Data Sheet doesn't say, but I assume that applying a high logic level to MODE sets full power mode, correct?

    EDIT: I guess the polarity of the MODE is indirectly specified in Table 3, 6, & 9 of the Data sheet:

    That still doesn't give the threshold limits.