David Brown

Vstby for battery backed internal ram

Discussion created by David Brown on Feb 17, 2012
Latest reply on Feb 17, 2012 by David Brown

I'm using an MC912DG128A.  I also have a separate RTC that will have a 3.0v battery to maintain its time when the system is powered off.


Can I also connect the battery to the Vstby pin on the HC12 to maintain the contents of the internal RAM?  The datasheet is very fuzzy about the use of that pin.  All it says is the minimum voltage is 1.5v, with a draw of 50uA.  


When the HC12 is powered, does Vstby continue to draw its 50uA?  Or does it internally switch off and run on the 5v supply?


I would assUme that I can connect the battery and be just fine, but want to make sure before I have circuit boards made :smileywink:


Thanks in advance,