Can the internal FET be disabled?

[FreshmanNewbie]

In this device, can the internal FET be disabled for the CRD_PWR pin?

Can the CRD_PWR pin be left floating?

I checked the page 24 of the datasheet.

But there's no explicit mention that the pin can be left floating. That's why I have this questions. So, if the internal FET be disabled through the register settings mentioned on page 24, then can I leave this pin unconnected?

 

[betwixt]

It appears to be a power output so just leaving it floating should be safe. As an output it should be low impedance and therefore safe from ESD but if in doubt add a high value resistor (100K?) to ground.

Brian.

 

[FreshmanNewbie]

It appears to be a power output so just leaving it floating should be safe. As an output it should be low impedance and therefore safe from ESD but if in doubt add a high value resistor (100K?) to ground.

Brian.

Hello Brian. Thank you for the answer.

Two questions:

1. In that case, so, I will leave that output unconnected. But could you tell me the logic on how you concluded that the output should be a low impedance once and hence safe from ESD?

2. Also, I checked page 24 of the datasheet. There are register settings for the FET. Can the internal FET be disabled through the register settings? Could you please confirm?

 

[betwixt]

I would stress I have no experience of this device so I'm going by the data sheet.

Yes, it can be turned off internally but if it is a power output, like almost all types of output, it wouldn't assume a high impedance state. Generally it is only inputs that have high impedance so they minimally load whatever is driving them. An input shouldn't be left floating as it could assume any voltage leaked or conducted to it so a pull-up or pull-down should always be present but outputs are normally OK.

Even if turned on internally, without a load it would probably just produce a high level voltage at the output but not draw any additional current.

Brian.