7805 IC requires minimum 6.5 volts to give 5 volt output. To monitor this, a Zener and LED are included at the input. Zener voltage is 4.7 volts and the forward voltage drop of the ordinary diffuse ...

78 XX series regulator IC can handle maximum 1 ampere current. The Regulator ICs require minimum 1.5 higher input voltage than their voltage rating. For example 7805 IC requires minimum 6.5 volts to ...