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LTC3569 EN Pins

I am designing a circuit with the LTC3569.

I want to operate it as 3 independent buck converters (1.2A, 0.6A, 0.6A).  I do not have any digital means of controlling the EN pins to set the reference voltages for each converter -- and am fine using the default value.

Questions:

1. Is the default value 0.8V?

2. What should I tie the EN pins to for the behavior described above?  I do NOT want slaved outputs  (which happen to be the only examples in the data sheet).  If I can't pull them to SVin, I assume tying them to SGND would disable that particular buck.  Is there some intermediate voltage?  Should they be floating?  Can I sequence them?  Meaning, tie EN1 to SVin, then EN2 to OUT1, and EN3 to OUT2?

Thanks in advance for your help!

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  • Update - somehow, I missed the example on p. 17 of the data sheet.  This seems to imply that:

    1. "Without toggling the EN pins, the LTC3569 develops a 0.8V reference voltage..."

    2. Just looking at it, all three are tied to SVin, but are not slaved together.  Does tying ENx to SVin allow slave outputs but not require it?

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  • Update - somehow, I missed the example on p. 17 of the data sheet.  This seems to imply that:

    1. "Without toggling the EN pins, the LTC3569 develops a 0.8V reference voltage..."

    2. Just looking at it, all three are tied to SVin, but are not slaved together.  Does tying ENx to SVin allow slave outputs but not require it?

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