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Unread 24-09-2010, 14:46
EricVanWyk EricVanWyk is offline
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Re: Generating EM field

Quote:
Originally Posted by SteveJanesch View Post
All good suggestions, Eric, but I have one clarification:



This statement is true as long as the circuit (coil) doesn't exceed the available source voltage of the driver, which I think is 3V for the Cypress PSoc (or is it running straight off the 5V USB?). It probably won't be a problem, but I'm just being cautious before learning the implementation details.

- Steve
You are absolutely correct. In current mode, you are limited to the source voltage. There is no boost circuit (except for the one that is built in to the chip but isn't in use...) active for this path.

I was assuming that your impedance would be significantly lower than 3V / 1mA = 3kOhms. 30AWG magnet wire is 100Ohms per 1000 feet, so 3kOhms of it would be a couple miles long, which likely wouldn't fit in a 3" cube

I don't remember if it is 3.0 or 3.3V or 5.0V (but I'm leaning away from 5.0V).