Mike M wrote:
>
> Hey, really dum question...  I have a small 5v, 75ma, 70ohm coil relay that i was fooling around with using a pic.  now if i attatch one end to +5v and the other end to the pic PORTB with the pin driven low the relay clicks.  If i attatch one end on the relay to ground and then the other end to a pin on PORTB driven high nuthing happens.  Now i assume that this is because the 16f84 can sink 25ma while only source 20ma right??  a 75ma coil though is like 3 times as much so shouldnt the pin being Low and the other end of the relay connected to 5v still not be able to have enought current only sinking 25ma to switch the relay?  YES I KNOW USE TRANSISTORS BUT IM JUST SAYING cause i know half of you are gonna reply relling me to use transistors to switch the relay ;)
>
> mike, again.

"Use HexFets, not bipolar transistors", Mike <G>

I didn't hear anything about a protection diode across the relay, Mike;
Even with a HexFet, it's still a good idea.

  Mark

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