Hi Friends,
I'm working with the LTC1155 high side driver IC. This IC has an internal charge-pump to boost your gate voltage well over your supply voltage to fully saturate your N-channel mosfet gate being used as a high side switch. No matter what I try I can't get the ic to provide gate voltage high enough to fully saturate the mosfet. This leads to the FET getting hot. I have included a pics to the circuit I'm using to test my setup and also a screen shot from my scope. I can't figure this out as this is my first time working with high side drivers and Mosfets being placed in the high side. Any help on what I'm missing would be appreciated.
The red line is my input squarewave at 12v 20KHZ into the IC. Yellow line is mosfet gate at 13.2V The internal charge pump in the IC should boost the gate to over 22V from 12v to fully saturate the MOSFET gate
I'm working with the LTC1155 high side driver IC. This IC has an internal charge-pump to boost your gate voltage well over your supply voltage to fully saturate your N-channel mosfet gate being used as a high side switch. No matter what I try I can't get the ic to provide gate voltage high enough to fully saturate the mosfet. This leads to the FET getting hot. I have included a pics to the circuit I'm using to test my setup and also a screen shot from my scope. I can't figure this out as this is my first time working with high side drivers and Mosfets being placed in the high side. Any help on what I'm missing would be appreciated.
The red line is my input squarewave at 12v 20KHZ into the IC. Yellow line is mosfet gate at 13.2V The internal charge pump in the IC should boost the gate to over 22V from 12v to fully saturate the MOSFET gate