So I’m working on the MMA7260Q 3-Axis Accelerometer and ran into several problems..
I’m powering the 3.3V accelerometer from the 5V arduino, and using a 3.3V voltage regulator. In spite of this, the chip still starts getting very hot.
2. Signal Jitter
I was getting a lot of signal jitter even when the accelerometer was just sitting idle. I started to use a decoupling capacitor and low-pass filter.
Capacitors store up electricity while current is flowing into them, then release the energy when the incoming current is removed. Sometimes they are polarized, meaning current can only flow through them in a specific direction, and sometimes they are not. If a capacitor is polarized, it will be marked as such on the diagram. Don’t wire a polarized capacitor backwards; it might explode.
A basic low-pass filter consists of a resistor and a capacitor. If you’re dimming an LED, start with a 10µf capacitor and a 220-ohm resistor, and experiment with different values from there to see what works best.
If you find the readings from your analog inputs are inconsistent (for example, you see changes on one channel when the sensor on a different channel is the one sensing action), it helps to decouple your input circuit. Decoupling means smoothing out the dips and spikes going into the circuit from the rest of your microcontroller circuit. To do this, place a 0.1microfarad capacitor from voltage to ground as close to where the analog input connects to voltage.
Accelerometer Ranges for 1st Iteration
2nd: add .1mF capacitor to accelerometer