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Stuart
23-05-2007, 16:48
ok Im working on something and I need to know how much power the TTL serial port can put out. basicly the question is weather or not I can run several (2+) microchips off of that +5v. but if I could get a # that would be great.

karlcswanson
23-05-2007, 17:00
I think the 5v on the RC can supply 1 amp, that is shared by all of the devices in or plugged in to the RC.
+5V Power Pin - The total combined current supplied from all 16 Analog and 18 Digital +5V Power header pins is 1 Amp. The 1 Amp max can come from a single +5V Power pin.
http://www.ifirobotics.com/rc.shtml#Specifications

Stuart
23-05-2007, 17:15
awesome!

John Gutmann
23-05-2007, 21:30
Yea but that doesn't mean you can safely pull an 1 amp through the chip. if the TTL serial port is connected to the uC then you can only source ( or sink ) as much current as a general IO pin because that is basically what the pin is.

-John

whytheheckme
23-05-2007, 21:46
I wouldn't worry too much about the safety of this....

For instance, if you short out a +5v pin and a gnd pin on a Digital I/O (for example), all that happens is the RC Hardware light comes on. It doesn't break anything. It just won't work.

My 2 cents.

Jacob

Stuart
24-05-2007, 21:43
no I was just looking for an answer over 100ma. I dont plan on running close to an amp.

John Gutmann
26-05-2007, 01:12
If you look in the data sheet look at the max sink/source per I/O and that is your answer.

-John

Eldarion
26-05-2007, 04:13
I think he is talking about the +5V that is available on that pin, not the actual TTL lines themselves. That +5V pin is tied directly into the 1A 5V bus in the RC.