the current for each lead goes through a resistor inside the controller, which you can see right next to where the wires are soldered onto the pcb. 3 in row, GBY leads going out on the other side.
when current from the 5V supply flows through the resistor, there is a voltage drop on the outer end of that resistor as the hall sensor 'sinks' the current to ground. the microprocessor detects this voltage drop and that sets the logic state to the microprocessor as to which of the phases should be active. you can see where the traces run from the end of the resistor back to the micro.
you want to measure the voltage on the outer end of the resistor, just like what the micro sees, as the wheel slowly, i mean slowly, rotates and the magnets move by the hall sensors. verify that all three hall sensors toggle between 5V and almost zero volts. you can also measure this on the wires in the 5 pin plug but since the controller is open just measure right on the trace, with the black probe on grd.
dnmun wrote: each one has to toggle on and off. when you know that then we can go look for the traces from the micro out to the integrated circuit device that drives the mosfet gates. the driver will be out by each of the mosfets, and the traces will all run together back to the same 3 sequential pins on the micro. gotta find them and then measure the voltages on those traces as you rotate the wheel. the mosfets don't have to be active to do this.
dnmun wrote:edit> just found this circuit richard drew on another thread
http://www.endless-sphere.com/forums/vi ... 14#p575114
i think this is exactly what you have for your input voltage regulation and the Q13 is the 7812, and the diode in the corner is the 20V zener and the resistor connecting them is the little surface mount to the left of the 12V regulator, or maybe it is Q17 for the mosfet and the R120 is the resistor
dnmun wrote: it does look like that is the 12V, looks like it runs over to one end of that 3 terminal device Q13, with the ceramic surface mount cap to ground in between, you took out the resistor that bridged from Vcc to the 12V. did you measure the resistor with your voltmeter? don't need it for this anyway.
dnmun wrote:wowowow, you did good.
those three traces from the micro are the signal to the mosfet drivers, and if you can see them switch on and off as the wheel turns, you can assume the micro is still functional and you should be able to use the controller again after swapping out the caps and the input resistor. i don't know if those traces will be high or low, but if they change logic state with the hall sensors, then you are home free. really good work to find those so far.
put the black on grd, and red on the three pins on the micro and let us know how it turns out. we can explain about richard's circuit and your input regulation later.
dnmun wrote: never did find out if the pumping diode D0A and the small charge storage cap next to it was blown up like i thought i saw in that picture.
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