AnsweredAssumed Answered

Is AREF pin break-out usable on FRDM-K64F?

Question asked by Todor Todorov on Feb 1, 2016
Latest reply on Feb 4, 2016 by Fang Li

Hi everyone,


If I read the board schematic correctly, the VREFH pin is tied to VDD through a jumper resistor (R54), and the jumper resistor (R53) which ties VREFH to the AREF break-out pin on connector J2 is not populated. I need to be able to apply an external 2.048 reference voltage via the AREF pin, but the way I see it, this won't be possible without performing surgery on the board.


Is this correct?


I also looked at the board reference guide and at the K64F sub-family datasheet, but was unable to find any way to achieve an internal reference voltage of 2.048V, except if I power the whole board from that voltage. It is either VDD or 1.2V.


Is there any chance I missed something and this is achievable either on the AREF pin-out without taking a soldering iron to the board, or through some register setting in the MCU?


Thanks for your help!