I am working on a project where the intent is to use an MMA8452 to sense 2 separate conditions. In short, it's a PCB to be mounted in a cell phone case, and LEDs will go on 1: if the phone vibrates and 2: if you physically pick the phone up.
I already have the PCB made and reflowed, and it's sending the interrupt to the micro when you pick it up. All the hardware works just dandy.
My problem is that I have the threshold set up around 1.3 G's (on all axes) so it doesn't trigger with every little movement of the phone - only when you physically pick it up. With that threshold, it's not enough to trigger on the vibration of the phone. .
Does anyone have any advice on how I could interrupt on a tiny movement (like vibration), and a larger threshold movement (like picking it up) at the same time? It's going to be driven on coin cells, so power consumption is critical - I don't want to be constantly switching back and forth with different settings and checking status every few ms.
I know, it's asking for 1 device to do 2 things at once, but thanks in advance for your thoughts.