Lm2576 noise issue in ds pic

[raman00084]

In my ds pic microcontroller board i am using lm2576 5v regulator in the previous boards i used 7805 due to heating problem i switched to lm2576 5v regulator my doubt is lm2576 ic operates at high frequency is there any possibilities of noise entering to pic micro controllers please suggest which is best for long run and noise free lm2676 are 7805


regards
kalyan

 

[Electro nS]

use both ,

set the lm2676 adjstable version to something like 7-8 V follow that by 7805 , you will get a clean output and very low heating in 7805

another option offcourse is to increase the decoupling capacitors of the lm2676 and use 1000uf electrolytic along with 1uF and 100nF ceramic

and in all cases watch out for your layout , i am 100% sure your layout is bad !!! this causes the noise in most cases

hope that helps