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Unread 21-06-2006, 23:11
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Re: Voltage-to-resistance converter for using any joysticks

Quote:
Originally Posted by Al Skierkiewicz
Jonathon,
If you are thinking of an electronic replacement for a joystick, the OI is already making the conversion. Remember that the joystick resistance is in series with the 5 volt supply and another resistor inside the OI. As the joystick resistance changes, the input voltage changes across the internal resistor. That is what is digitized by the input A/D convertor.
Ahhh sorry, I didn't make it clear, I meant to use that circuit so you can use joysticks with non-100k pots in them (there are issues with using pots that aren't 100k, correct?)
Though, now that you mention the architecture of the internal circuitry, you could just get away with an op-amp with enough output current so that the pull-down resistor doesn't affect the voltage to the ADC.
cool
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