Engineering Design 4 EEET2268 EEET2267 Final Year Project RMIT University
Resonant Frequency at 1.3 MHz
Runs fine between 8.5VDC - 12VDC (Greater than 12V draws too much current and heats up capcitor Bank)
Receiver LC tank ... UF4004 Diode Bridge... Tantalum Electrolytic Capacitor Smoothing... LM2575 Step Down Buck Converter IC Regulator... 5V out to USB plug... (Vcc 5v, D+ 2.0V D- 2.8V, GND)
LM2575 Switching Buck Converter chosen because input voltage ranges between 5-20V peak at proximity of sensor. Low Heat,
LM7805 would heat up substantially!
@bnwag Have a look at your toothbrush charger and read the specs about the input/output current... generally the iPod will not charge under 500mA, Also, to get the basics right, use a multimeter between your coils to see if there is even 5V being delivered. the iPod has a weird data pin voltage of 2v and 2.8v in order to allow a charge also. The Power supply i used was outputting about 1-1.5A to charge the iPod which was only a few cm away. ... some points to consider in your own design @bnwag
azndaudau 2 months ago
I'm trying to do something similar with a couple of electric toothbrush charges and an iPod cable coiled to make the secondary winding, but even with two primary windings I don't think it will work. I don't think I'll be able to induce enough current for it to be feasible.
It's great to see that you've got it working - this at least tells me what I'm trying to do is possible.
bnwag 2 months ago