vonsproken
Member
Hi, I'm building a circuit that must send a 15V signal to IGBT but must be isolated. My first part of the circuit has a 300V difference between the second part and therefore cannot share the same ground. This signal must not have more than a 300ns delay to the output. I thought of using a transformer - any other ideas will be welcome.
I built an oscillating circuit - this is my signal source.
I then power a TC4428A chip to give an AC signal to drive a transformer, this chip has an inverting and non inverting output.
The transformer has 20 turns primary to 10turns secondary wound on a ferrite core.
I manage to get a perfect squarewave out of the transformer.
This is my problem - When I connect it to a comparator I get an output but when I connect this output to anything else I get a huge amount of noise coming from the comparator - I have tried 393 and 311's and they do the same. I'm not sure what part is wrong. The output needs to be able to drive a TC4422A mosfet driver chip.
I can provide pictures if neccessary, I cannot have any more that a 300ns delay between the signal input and the output. I do not want to use high side driver chips as the voltage difference in my circuit may become 700V in the future - I'm not aware of any cheap high side driver chips that can do this, please notify me if there are any.
I built an oscillating circuit - this is my signal source.
I then power a TC4428A chip to give an AC signal to drive a transformer, this chip has an inverting and non inverting output.
The transformer has 20 turns primary to 10turns secondary wound on a ferrite core.
I manage to get a perfect squarewave out of the transformer.
This is my problem - When I connect it to a comparator I get an output but when I connect this output to anything else I get a huge amount of noise coming from the comparator - I have tried 393 and 311's and they do the same. I'm not sure what part is wrong. The output needs to be able to drive a TC4422A mosfet driver chip.
I can provide pictures if neccessary, I cannot have any more that a 300ns delay between the signal input and the output. I do not want to use high side driver chips as the voltage difference in my circuit may become 700V in the future - I'm not aware of any cheap high side driver chips that can do this, please notify me if there are any.