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fadibasic
- 10th May 2008, 18:30
Hi guys,
I am not sure if it will be an issue or not, but I want to ask a question about portA.4
I have read the spec sheet, and PortA.4 is an open drain, which means current will always flow to the microchip.
what I am worry about is if the microchip is safe if I have a transistor (emitter side) connected to the pin, the Base (B) connected to the 5 Vdc and the collector (C) to 24Vdc.

Can PortA.4 be configured so that it becomes an output. so that it behaves just like the other PortA pins.

sayzer
- 10th May 2008, 18:40
Why don't you pull this pin to Vdd with a resistor, say 10K or 4K7 ?

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fadibasic
- 10th May 2008, 19:11
Please can you explain to me what happens if we do that?
what do you mean by PULL? like I split the current going to PortA.4 with VDD.