Hello,
I am using two IR2110 mosfet drivers, one for each side of my H-bridge. I visualized the output of the H-bridge (a 100kHz square wave between +12V and -12V) on an oscilloscope, using a differential voltage probe. That was fine.
However, when I connect a load to the H-bridge, and I measure with a multimeter the AC voltage across the load, one of my drivers gets broken.
It also happened once while measuring across the load with the oscilloscope instead of the multimeter.
When measuring with both, I see that the square wave on the scope collapses completely when measuring the voltage with the multimeter. I can't understand why, as a voltmeter has a very high input impedance. It even happened once when connecting only one probe of the multimeter (one sided)!
My load is a LC resonant circuit for wireless power transfer.
I'm really looking for a clarification, as this frustrates me.
I am using two IR2110 mosfet drivers, one for each side of my H-bridge. I visualized the output of the H-bridge (a 100kHz square wave between +12V and -12V) on an oscilloscope, using a differential voltage probe. That was fine.
However, when I connect a load to the H-bridge, and I measure with a multimeter the AC voltage across the load, one of my drivers gets broken.
It also happened once while measuring across the load with the oscilloscope instead of the multimeter.
When measuring with both, I see that the square wave on the scope collapses completely when measuring the voltage with the multimeter. I can't understand why, as a voltmeter has a very high input impedance. It even happened once when connecting only one probe of the multimeter (one sided)!
My load is a LC resonant circuit for wireless power transfer.
I'm really looking for a clarification, as this frustrates me.