Looking at the datashet of the SN75176B http://www.ti.com/lit/ds/symlink/sn75176b.pdf for information on how to decode the ordering information on this part.
SN75176B x y z
x: D = SOIC; P = PDIP; PS = SO housing
y: blank : Tube (75 pcs) ; R : Real (2500 pcs)
z: blank ?? ; E4 = ??; G4??
Can you point me to the missing information regarding E4 / G4 ?
Thanks and best regards
Stefan