Best way to power cycle 5-19V device

[bryce1]

Hi guys,

I have developed a watchdog device that can power cycle a device by cutting of power via a low side n mosfet switch. As I want to make this a bit more professional, I wanted to pick your brains. Some people I talked to considered the low side switch a bad idea because you dont know what happens inside an embedded device if you take away ground.

How do I do this "better"?

As the attached device is not always the same one, I can only work from the spec of 5-19V up to 1.5A.

Thanks!

[Rerouter]

use a high side with a charge pump?, if you have any other connections other than power to the end device that are not isolated, you may damage things when there inputs suddenly go from ground to -15V

[Jeroen3]

The enable pin on the regulator.

[bryce1]

There is no regulator, the device sits between the wallwart and the device.

use a high side with a charge pump?, if you have any other connections other than power to the end device that are not isolated, you may damage things when there inputs suddenly go from ground to -15V

The other connection is ethernet, so it is opto-isolated.

[matseng]

There is no regulator, the device sits between the wallwart and the device.

The other connection is ethernet, so it is opto-isolated.

Unless you are having a opto-fibre Ethernet the isolation device would be a small transformer, not an opto coupler...  But it's still isolated so that shouldn't be a worry here... ;-)

[Simon]

If you are removing power from the whole negative of a device it would be ok but if that is connected to other power references then you may have a problem, if your not using much power a P channel mosfet will do it, as mosfets gates can work from 1-15V you should have no problem getting a potential divider ratio that will work for a varying range.