keithma
Newbie level 5
sensor design
Hellow, everyone!
I want to design a frequency sensor to detect the signal frequecy. When the frequency is lower than 3M, the sensor will work to alarm. Because there is no reference clock , so the counter-based method will not work here. I decide to first change the frequency into voltage with a charge integration circuits , and then compare the voltage with a reference voltage coressponding to 3M. But because of charge injection this method is not so accurate. Any one with good idea?
Hellow, everyone!
I want to design a frequency sensor to detect the signal frequecy. When the frequency is lower than 3M, the sensor will work to alarm. Because there is no reference clock , so the counter-based method will not work here. I decide to first change the frequency into voltage with a charge integration circuits , and then compare the voltage with a reference voltage coressponding to 3M. But because of charge injection this method is not so accurate. Any one with good idea?