Re: SuperQBoard Affecting Display
Posted: Wed Oct 28, 2015 12:13 am
Certainly if there are electrolytic capacitors, renew these first. The lifespan of electrolytic capacitors is limited. And affected by heat.
All series regulators of the LMxxx or 78xxx type need suitable capacitors on both the input and the output. Otherwise either the regulator feedback system (in the on board chip) may cause oscillation of the 5V rail (which also affects the input supply). Or it will be unable to correctly handle noise on the input supply.
If after fitting new capacitors, there are still problems, the 7805 may have been partly damaged, so yes, try fitting a new one. Having said that, the 78xxx regulators are fairly hardy and don't often go wrong (unless mistreated).
Mark
All series regulators of the LMxxx or 78xxx type need suitable capacitors on both the input and the output. Otherwise either the regulator feedback system (in the on board chip) may cause oscillation of the 5V rail (which also affects the input supply). Or it will be unable to correctly handle noise on the input supply.
If after fitting new capacitors, there are still problems, the 7805 may have been partly damaged, so yes, try fitting a new one. Having said that, the 78xxx regulators are fairly hardy and don't often go wrong (unless mistreated).
Mark