Hi. I'm new to this forum, so, first, hello to all of you. I'm kinda new to electronics, I've learned all online, and I've made some simple projects with spare parts like a bench power supply with an old dot matrix printer transformer and things like that.
I tried to make a 12VDC to 120VAC inverter like a month ago, with two NPN transistors , but I couldn't find the center-tapped transformer, as in my country it's very hard to find electronic stuff.
Now, I tried to make a better inverter with a full H bridge, so I could use all kinds of transformers, not just center-tapped transformers. I assembled it in a breadboard, and used an wall wart AC to AC adapter(just a transformer inside a nice plastic case) backwards, using the secondary 9V as primary, and it works fine, and I powered a radio and several small appliances.
My problem is that, When the supply voltage for the circuit is less than 12V, the P-Channel MOSFETS are cold to touch, but when voltage is higher than 12V they become warm even without a load. I got a borrowed oscilloscope, and I see that it's like that the P-Channel MOSFETS take a little while to turn off. I think you can help me.
The schematics are in the attachment. Thanks in advance.
I tried to make a 12VDC to 120VAC inverter like a month ago, with two NPN transistors , but I couldn't find the center-tapped transformer, as in my country it's very hard to find electronic stuff.
Now, I tried to make a better inverter with a full H bridge, so I could use all kinds of transformers, not just center-tapped transformers. I assembled it in a breadboard, and used an wall wart AC to AC adapter(just a transformer inside a nice plastic case) backwards, using the secondary 9V as primary, and it works fine, and I powered a radio and several small appliances.
My problem is that, When the supply voltage for the circuit is less than 12V, the P-Channel MOSFETS are cold to touch, but when voltage is higher than 12V they become warm even without a load. I got a borrowed oscilloscope, and I see that it's like that the P-Channel MOSFETS take a little while to turn off. I think you can help me.
The schematics are in the attachment. Thanks in advance.
Attachments
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