Hi again everyone
Thanks for all the help getting me this far. I just have a few questions before I can start building this (I hope) so if I can get some help please it would be great
I have attached the diagram below and everything switches ok and the output is nice in simulation. I just wanted to checkout the MOSFET setup and selection if that's ok.
Basically
1) They are all N-channel MOSFETS is this ok and the correct way to set this up optimally.
2) The MOSFET I have selected have a GSth of 3.5-5 V so the supply (mark x on the diagram) to the phototransistor component of the opto-isolator is too high or ok? The reason I ask is that the source voltage of MOSFET y and z (marked) won't be 0V.
3) This is the first time I've used MOSFETS and this is an inverter for a 12V car battery (30-40A). The MOSFETs I've looked at have an IDs of over that and power dissipation of over 400W but they seem tiny with tiny legs. Can they really handle this?
4) Finally, do I need the gate resistors?
Like I said this did work in a slowed down sim but I don't trust it over someones experience so I'd appreciate any help.
Thanks all
Link to MOSFET datasheet http://www.irf.com/product-info/datasheets/data/irfp4668pbf.pdf
Diagram
Edit : Link to the previous topic -- Scott Wang.
1. CMOS 7555 abstable output @ 800 KHz - trangular wave instead of square, slew rate problem?
Thanks for all the help getting me this far. I just have a few questions before I can start building this (I hope) so if I can get some help please it would be great
I have attached the diagram below and everything switches ok and the output is nice in simulation. I just wanted to checkout the MOSFET setup and selection if that's ok.
Basically
1) They are all N-channel MOSFETS is this ok and the correct way to set this up optimally.
2) The MOSFET I have selected have a GSth of 3.5-5 V so the supply (mark x on the diagram) to the phototransistor component of the opto-isolator is too high or ok? The reason I ask is that the source voltage of MOSFET y and z (marked) won't be 0V.
3) This is the first time I've used MOSFETS and this is an inverter for a 12V car battery (30-40A). The MOSFETs I've looked at have an IDs of over that and power dissipation of over 400W but they seem tiny with tiny legs. Can they really handle this?
4) Finally, do I need the gate resistors?
Like I said this did work in a slowed down sim but I don't trust it over someones experience so I'd appreciate any help.
Thanks all
Link to MOSFET datasheet http://www.irf.com/product-info/datasheets/data/irfp4668pbf.pdf
Diagram
Edit : Link to the previous topic -- Scott Wang.
1. CMOS 7555 abstable output @ 800 KHz - trangular wave instead of square, slew rate problem?
Last edited: