packages
I've received chips PCA9306DCTR (from Texas Instruments) but they don't have any dot or notch to define it's orientation (i.e. where is the pin 1).
In the datasheet there is a picture of this chip (in SM8 package) and it has a notch. However chips I've received has only strip of different color (please see the picture) and I've not found any information about it's meaning.
So, is this strip mark pins GND and EN (i.e. the same as dot or notch) or it marks SDA1 and SDA2?
It's a (granted, fugly) TO-220 derived package used by Allegro for current measuring parts like the ACS756, datasheet. (I don't know if other manufacturers also use this kind of package.) The thick bent connections are for the current to be measured, in the case of the ACS756 up to 50A. This requires careful PCB layout (yes, the heavy pins are soldered in a PCB \$-\$ obviously not suited for paste-in-hole reflow, and hand-soldering will be tough as well :-))
Possibly other manufacturers prefer screw connections for low resistance current shunts like these ones from Isabellenhütte:
I don't know why Allegro prefers soldering over screw mounting.
I found this application, also based on an Allegro device (ACS715) which uses indeed screw connections.
What I find strange is that they pump 30 A through two ordinary SOIC pins. I would at least have replaced pins 1-2 and 3-4 by two tabs, I think. 15A through an SOIC pin seems like a lot.
TO-3 is much more labor-intensive during assembly. Also, the TO-3 package is more expensive to manufacture
It's actually cheaper overall to use several TO-220 devices or a TO-247 device.
Best Answer
The stripe marks the Pin 1 end. With Pin 1 to the left, the rest of the text is right way up, as further confirmation - as has been the convention on all DIP ICs (and SOIC) I have ever seen.