Good Afternoon,
Recently I have made a wireless power transfer circuit for a project of mine. The goal is to illuminate an LED roughly an inch away. To do this I used a 555 timer to create a square wave that drove an NPN transistor with a 28.5 uh coil. Testing on the breadboard it worked fine but as soon as I made a PCB for it, the distance it worked decreased dramatically. Now, it is spotty and I am lucky if it works up to half an inch. Initially, I thought that with the PCB traces capacitance was added that affected the resonance but after measuring with a multimeter it hadn't changed. Below I have attached the schematic and PCB files. If anyone has any advice I greatly appreciate it.
PS: One thing that has eluded me is why the signal I measure from the output of the timer is roughly 60khz. This doesn't match what the values are. Also, it is worthy to note that when driven with a function generator, the circuit performs well in this range. (50-70khz)
Recently I have made a wireless power transfer circuit for a project of mine. The goal is to illuminate an LED roughly an inch away. To do this I used a 555 timer to create a square wave that drove an NPN transistor with a 28.5 uh coil. Testing on the breadboard it worked fine but as soon as I made a PCB for it, the distance it worked decreased dramatically. Now, it is spotty and I am lucky if it works up to half an inch. Initially, I thought that with the PCB traces capacitance was added that affected the resonance but after measuring with a multimeter it hadn't changed. Below I have attached the schematic and PCB files. If anyone has any advice I greatly appreciate it.
PS: One thing that has eluded me is why the signal I measure from the output of the timer is roughly 60khz. This doesn't match what the values are. Also, it is worthy to note that when driven with a function generator, the circuit performs well in this range. (50-70khz)
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