J_M_B
Junior Member level 2
I need to decouple two circuit blocks.
The spec for the low noise block is 10mvpp ripple max.
Adding 3 100uF ceramic capacitors allows me to achieve my 10mvpp spec
However this will be a costly solution.
I have been advised an RC filter in the power may be effective and simulation with 10R/100uF does look like it will bring me into my 10mvpp spec.
However I thought it was bad practice to add impedance to a power rail - as I am adding a 10R resistor
(If I reduced R, would have to increase C therefore defeating the object of using RC as cost saving measure)
I am struggling to find much info anywhere about this.
Could anyone advice if it should be acceptable to add 10R series resistor to power rail?
Is it bad practice?
Could it possibly cause EMC problems?
Would really appreciate any advice
Cheers
Jamie
The spec for the low noise block is 10mvpp ripple max.
Adding 3 100uF ceramic capacitors allows me to achieve my 10mvpp spec
However this will be a costly solution.
I have been advised an RC filter in the power may be effective and simulation with 10R/100uF does look like it will bring me into my 10mvpp spec.
However I thought it was bad practice to add impedance to a power rail - as I am adding a 10R resistor
(If I reduced R, would have to increase C therefore defeating the object of using RC as cost saving measure)
I am struggling to find much info anywhere about this.
Could anyone advice if it should be acceptable to add 10R series resistor to power rail?
Is it bad practice?
Could it possibly cause EMC problems?
Would really appreciate any advice
Cheers
Jamie