When ordering Panjit transistors such as PJC138K_R1_00001, you can receive parts with a pair of characters on one end of the device stacked on top of each other, such as ‘E3’. What does this ‘E3’ marking mean?
‘E3’ is an internal tracking marking from Panjit, in this case. It has no impact on the product’s specifications or performance, and can safely be ignored.