I am trying to read piezo accelerometer ACH-01
data with Arduino;
I am confused with interface circuit it requires. Data sheet says it need biased power supply and provides a simple schematic with -5V/+5V supply; there is another uni-polar alternative
with two op-amps;
Is there any simpler way to interface Arduino with this accelerometer?
If I connect it to Gnd, +5V and to analog ping through RC high pass filter, it shows accelerations, but only top half of acceleration wave - I vaguely understand it has something to do with that biasing.
Another thing I don't understand about it - why it requires high-pass filter?
I tried connecting it directly to gnd, +5V and analog pin to read output voltage; when untouched the output is about 0; if I give it a little knock, the output momentarily goes to 2-3 V and then goes back to zero _very slow_, like, for a second or so. Why?