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7 years, 5 months ago.
FRDM-K64F: Wrong power specs in technical reference?
I was looking at the specs for the FRDM-K64F board and I recognized that the power specifications on the platform page (http://mbed.org/platforms/FRDM-K64F/) seem to be wrong. The datasheet (http://cache.freescale.com/files/microcontrollers/doc/data_sheet/K64P144M120SF5.pdf) states in chapter 1.4 that a digital I/O pin can source or sink 25 mA at maximum. Your technical reference says only 4 mA.
Furthermore table 4 in chapter 2.2.3 states a maximum output current of 100 mA for all ports together which is much lower than the 400 mA listed in the platform reference. Maybe I'm wrong but I don't think that you simply can add up all the output high and output low currents to achieve the 400 mA since chapter 1.4 limits the maximum digital supply current to 185 mA.
And as a bonus it would be nice to see an explicit list of 5V tolerant inputs. I think it would be very useful for beginners to know where they can put 5V on and where not without studying the manual.
7 years, 3 months ago.
Hi Tobi, I recall there being 5V tolerant inputs on the FRDM-K64F. I thought all were, but clearly that's not the case. Can you point me to the page in the datasheet that mentions which are 5V tolerant? I have gone over it twice, and I could only find footnote 1 on page 7 that says, "All 5 V tolerant digital I/O pins are internally clamped to VSS through an ESD protection diode", but I couldn't find anything regarding such inputs elsewhere in the datasheet.