frankzappa
Well-known member
Hello!
I’m wondering what I can do to clean up the power supply noise/ripple. I’m using some piezo sensors with a virtual ground circuit. I buffer the sensors and virtual ground with op amps and I’m getting pretty clean signals after digital filtering but I’m wondering what I can do to clean stuff up electrically to get the best possible signals as I didn’t use any capacitors anywhere in the circuit.
I’m thinking to put a 0,1uF and 10uF on the op amps power input to ground.
Also maybe a 220uF between 3.3v and ground on the teensy.
The virtual ground is a voltage divider with two resistors to create a halfway point between 0-3.3v. I also put this through an op amp before going to the sensors.
Should I put a capacitor there as well?
Is there any point to put a ferrite bead on the power supply to make sure any digital switching stuff on the teensy doesn’t find it’s way to the analog circuit?
Also since the PCB will be submit to vibrations, I’m thinking I should avoid ceramic capacitors because of piezoelectric effects. What other choises besides ceramic capacitors do I have.
Any advice?
I’m wondering what I can do to clean up the power supply noise/ripple. I’m using some piezo sensors with a virtual ground circuit. I buffer the sensors and virtual ground with op amps and I’m getting pretty clean signals after digital filtering but I’m wondering what I can do to clean stuff up electrically to get the best possible signals as I didn’t use any capacitors anywhere in the circuit.
I’m thinking to put a 0,1uF and 10uF on the op amps power input to ground.
Also maybe a 220uF between 3.3v and ground on the teensy.
The virtual ground is a voltage divider with two resistors to create a halfway point between 0-3.3v. I also put this through an op amp before going to the sensors.
Should I put a capacitor there as well?
Is there any point to put a ferrite bead on the power supply to make sure any digital switching stuff on the teensy doesn’t find it’s way to the analog circuit?
Also since the PCB will be submit to vibrations, I’m thinking I should avoid ceramic capacitors because of piezoelectric effects. What other choises besides ceramic capacitors do I have.
Any advice?