Thread: Potentiometers in Analog Inputs
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Unread 12-11-2008, 00:30
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Re: Potentiometers in Analog Inputs
Quote:
Originally Posted by EricVanWyk View Post
the minimum resistance of the potentiometers is dictated by current draw and heat dissipation. You may draw up to 750mA for one analog sensor* (3A total), which would limit you to about 7 ohms. However, this would dissipate about 4 Watts, which is probably not what you want.

At 22 Ohms, you will dissipate roughly a watt. Make sure that your potentiometer can handle it.
At the risk of looking like an EE neophyte, can you explain how amperage draw, the resistance (ohms) and the energy dissipated are related? There must be a formula for that.

Thanks