4.7v as HIGH on digital output instead of 5v I'm new to Arduino, just got my starter kit, and I noticed that digital outputs 3 &amp; 4 have 5v as HIGH level while 5 to 13 have 4.7v as HIGH level.
Is it as it suppose to be?
Also depends on what your driving via this output. Standard TTL is:



But CMOS will be a bit different: