So today I woke up in the morning and got the idea to make a bicycle phone charger and I wanted to use a MOSFET and an LM7805 voltage regulator.
The generator I have would be turned on by the wheel and it would generate a voltage between 1 and 7 volts. If the voltage is over 5 volts it would get regulated by the LM7805 but if it is under 5V, it can't be regulated because the LM7805 can't step up voltages so I thought that I might use a logic level MOSFET as a switch. Basically, if the voltage is under 5V, the MOSFET won't allow it to go trough, but if it is above 5V, it could go trough.
I can't seem to understand how to wire up a MOSFET to do that, but I have tried something (the picture below).
Please help me and sorry if I make noob mistakes, I'm fourteen and I am just learning basics of electronics for now.
The generator I have would be turned on by the wheel and it would generate a voltage between 1 and 7 volts. If the voltage is over 5 volts it would get regulated by the LM7805 but if it is under 5V, it can't be regulated because the LM7805 can't step up voltages so I thought that I might use a logic level MOSFET as a switch. Basically, if the voltage is under 5V, the MOSFET won't allow it to go trough, but if it is above 5V, it could go trough.
I can't seem to understand how to wire up a MOSFET to do that, but I have tried something (the picture below).
Please help me and sorry if I make noob mistakes, I'm fourteen and I am just learning basics of electronics for now.
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