Sunday, 23 February 2014

filter - DC motor noise filtering


I have some brushed motors near to a 433 MHz RF receiver. They're controlled by a 490 Hz PWM signal. The electrical noise they produce is not a problem for the circuit, but it is for the receiver.


How can I reduce the noise, at least on the frequencies interfering with the transmitter?


I read that putting a ceramic capacitor across the motor's terminals and one from each terminal to the motor's case would help; if it's true, what size should they be? I unfortunately don't have technical information about the motors. I'm quite sure they're the same as those, but there isn't much data on that site...



Answer





I read that putting a ceramic capacitor across the motor's terminals and one from each terminal to the motor's case would help; if it's true, what size should they be?



You read the truth. Keep the leads to the caps short. 10nF is a reasonable sort of size, but you can go bigger or smaller if you have other sizes to hand.


No comments:

Post a Comment

arduino - Can I use TI's cc2541 BLE as micro controller to perform operations/ processing instead of ATmega328P AU to save cost?

I am using arduino pro mini (which contains Atmega328p AU ) along with cc2541(HM-10) to process and transfer data over BLE to smartphone. I...