MP2459GJ EN pin max voltage

DC-DC Power Converters
1

Hi. The MP2459GJ datasheet says that the absolute max voltage in “other pins” can go up to 6V. But in the EV2459-J-00A evaluation board (which uses the same voltage regulator) has a voltage divider in EN pin formed by a 100K and a 26.1K resistors, same as indicated in the component datasheet. Also in the EV2459-J-00A evaluation board can work up until Vin = 50V, which results in 10,34V in EN pin. In order to reach the absolute max voltage in EN pin, Vin must be 29V. The EN pin can reach higher voltages?

Is there any known effect if I just tie EN to Vin without this voltage divider? Or at least, keeping only the 100K resistor from Vin to EN limiting only the current that flows in to EN pin, but keeping a higher voltage?

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2

If you leave out the 100k it is almost a certainty that the part blows up, try it and see.
If you leave the 100k in then the voltage at the EN pin will rise to about 6.5V and then an internal zener will clamp the voltage at about 6.5V .

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