I would like to know about the Pin out of Arduino Mega. for arduino mega pin that I have used for 2 pieces of RFID reader, for relay, for RTC DS3231. however I am confused whether the SD card module can be used on Arduino Mega. thank you
retrolefty: LOL, we've had this same discussion before.
There is also nothing stating that you can take the sum, of all those individual port limits, as the maxiumum chip current draw limit. And no where in the datasheet does it state that 800 ma of total current draw is allowed. And of course as I've stated before the absolute maximum section lists the 200 ma figure. Why would they state 200ma there if it only applied to one port? Your assumption, and it is just an assumption, is in error, IMHO.
But that is why I would like others to comment on the subject, as you and I. while still respectful of each other's opinion, have not been able to come to consensus on the matter now or in the past.
My answer (not counting AVCC): Uno DIP: max. 200 mA (1x VCC/GND) Uno/Nano SMD: max. 400 mA (2x VCC/GND) Leonardo/Micro: max. 400 mA (2x VCC/GND) Mega 2560: max. 800 mA (4x VCC/GND)
I send support ticket to Microchip. Question was about absolute max. current for ATmega 8-bit AVR entire packages.
Answer from Microchip Engineering Support: The specification 200 mA max is for each pair of the VCC-GND pin. If a package has 2*VCC/GND then it will be 400mA. If the device is operating within the datasheet specifications, the device should not heat up and hence heatsink is not required.
@MarekBujko, you have responded to a 5 years dead question.