I AM USING ARDUINO MEGA 2560 WITH ETHERNET SHIELD FOR ONE PROJECT .THE VOLTAGE AT PIN 5 GOES ABOVE 6V AND ARDUINO STILL WORKING BUT THE ETHERNET SHIELD MALFUNCTIONING . HOW TO REDUCE THE VOLTAGE PLEASE SHARE ME. I USE ARDUINO MEGA AS SERVER TO CONTROL RELAYS USING DIGITAL INPUTS OF 5V . THE RELAY OPERATES AT 7.5V SOURCE BOTH GROUND ARE CONNECTED. I MEASURED THE GND PIN AND 5V PIN OF ARDUINO IT SHOWS 6.5 V