Supply Voltage Monitor

[craigcarder]

Hello,

      Is the Kinetis K60 able to monitor it's own supply voltage, for instance on an internal analog input?  If I want to monitor that voltage do I need to use one of the A/D pins and divide down the voltage?  I"m just trying to come up with a simple way to monitor supply (battery) voltage.

Thanks

Craig

[Paul_Tian]

Hi, Craig

If you only want to generate a warning alarm for own supply voltage, my suggestion for you is that you can use LVD (Low voltage detection) function to generate an interrupt.

Hope my reply can help you.

Best Regards

Paul

[gpontis]

There is no internal ADC channel that can monitor the power supply. In all my designs I put a voltage divider on each supply that I want to monitor, then connect that to a spare ADC input. If you are sensitive to wasted battery power, you could switch the divider in with a FET or use large value resistors with a bypass capacitor, say 0.1uF or so. In a system that is not limited to using a high impedance divider, it is also practical to connect the same monitor to a comparator input. You can use that comparator function to get an immediate notice when power is going down.