At about 9 volts the current suddenly jumps to about 25 mA. Then the lightning bolt appears but no significant current is drawn. As the voltage is increased, nothing happens until about 8 volts. Now since the magnet is in the playbook, then you need iron to complete the magnetic circuit, and the clips may be doing that (although I doubt it). The magnet seems to be in the playbook because the tiny alligator clips I am using are attracted to the pin area (they are made of steel I guess). I'd like to know more about this magnetic switch because I am currently charging it without the proper connector.
Sent from my BlackBerry 9900 using Tapatalk To test voltages you have to open it and check inside or finely splice three wires outside the pins to connect a voltmeter to once the charger is connected to the pins. In the meantime, if anyone knows anything official, your input would be greatly appreciated.Newbs, the pins provide a magnetic connection that then activates the electrical circuit inside, i,e its a clip+switch. I'll try to make a more rigid connection and get more accurate data. In the meantime, if anyone knows anything official, your input would be greatly appreciated.Īll these numbers are very approximate since it is very difficult to try and simultaneously hold wires against those small pins, look at meter readings, and turn dials. you see the lightning bolt at even less than 50 mA.Īll these numbers are very approximate since it is very difficult to try and simultaneously hold wires against those small pins, look at meter readings, and turn dials. the two outside pins appear to be shorted together internally the pins are Gnd/V/Gnd where V appears to be greater than 10 volts for charging beyond 50 mA When you say that one of the pins went to a chip in the charger, would that just have been the positive output of the regulator supply that went to the middle connector? A measurement of the resistance between the two outside pins gave zero ohms, at the most 0.1 ohms. Also it did not matter which of the outside pins I used for the ground. It maxed out at 50 mA at a voltage of about 10 volts.
I then reversed the connection and did get a current.
The first thing I noticed is that by applying the positive voltage to either end conductor drew essentially zero current. So with your information, I got a current limited power supply, limited the current to 50 mA and applied a varying voltage to it. I was surprised at the 12 V since the USB charger is only 5V. I'm happy with the chargers as they are for now (aside from known issues) so I'm not going to get out my scope to dig deeper for now. These things suggest that it's not a simple 12V/ground/12V situation, but rather than one of the pins has some form of data on it, superimposed on the power "signal", and that it may be more than trivial to reverse engineer any of this. I had pointed out, however, that one of those pins was connected internally to a chip in the charger, whereas the other was not, and we've also noted that reversing the connector will lead to it showing the lightning bolt symbol onscreen yet not actually charging all the time (for those with defective chargers where one of the three pins is slightly lower than the others). There are old threads where we identified which pin was which, purely in a voltage sense. Measuring on the PlayBook would, I hope, not show you much of anything. There certainly are measurable voltages on them, if you're measuring on the charger.
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