LM5116 VCCX Open

Kura,

We don't recommend that the VCCX pin be left open, if not used it should be grounded. 

If it is left open and there is a capacitor on the VCCX pin, there should not be any catastrophic failures.

  If it is left open with no capacitor, you may have noise coupled into the controller and there maybe erratic controller behavior.

Terry

Terry-san

Thank you for your reply.

I checked that there is a capacitor on the VCCX pin or not to customer.

There is a capacitor on the VCCX pin.

Does this cause any catastrophic failure?

Kura,

No it should not result in a catastrophic failure.

Terry

Terry-san

Thank you for your reply.

I understand that to place capacitor on VCCX pin doesn't cause "catastrophic failure".

What kind of failure to place capacitor on VCCX cause?

Kura,

Are you asking if there is a capaciot on the VCCX pin, what would cause it to fail?  If so I would think an over voltage. 

Terry

Terry-san

Thank you for your reply.

An over voltage means ,Is there possibility that VIN voltage appear to VOUT ?

Vin can appear on Vout if the High side buck Fet is shorted.

Terry