Axe_Murderer
New Member
I've built a project that is now in my car. It works great when the car is not running, and works jusy "okay" when the car is running. I have some temperature sensors (LM34) that produce pretty wild variations in read-out only when the car is running. Because of this I'm feeling pretty sure that the problem lies with noise/ripple on my power supply (feel free to disagree if you have an idea).
The power supply I've built is the usual design I use, a pair of caps flanking a voltage regulator. Since this is going into my car I used a pretty big cap on the input side, 2200UF 35V, with the usual tiny cap on the output side, a .010UF. I'm thinking that maybe I didn't put a big enough cap on the output side to deal with the noise? Or maybe the input side is too big and not buffering high frequency noise well enough? Obviously I don't know so that's why I'm checking with you folks.
If you have a suggestion on how I can improve the ripple rejection on my p/s I'm all ears!
Thanks.
-Mark L
(P.S. the project web page, not really populated much yet: www.markdepot.com/multi )
The power supply I've built is the usual design I use, a pair of caps flanking a voltage regulator. Since this is going into my car I used a pretty big cap on the input side, 2200UF 35V, with the usual tiny cap on the output side, a .010UF. I'm thinking that maybe I didn't put a big enough cap on the output side to deal with the noise? Or maybe the input side is too big and not buffering high frequency noise well enough? Obviously I don't know so that's why I'm checking with you folks.
If you have a suggestion on how I can improve the ripple rejection on my p/s I'm all ears!
Thanks.
-Mark L
(P.S. the project web page, not really populated much yet: www.markdepot.com/multi )