Any chance of getting them to make the pin 1 mark less symmetrically placed on the package. Like closer to the side with the pin 1. I've always found it confusing how some manufacturers use two symmetrically placed indentations.
Pins always number anticlockwise from the top (because vacuum tubes number clockwise from the
base side). Never seen an exception to this, just remember it and the marking is unambiguous.
Besides how can you orient the chip wrong, there are only 4 ways to place a square chip!! So long as the
silk-screen has a blob in the right corner its foolproof.
A description like that is far from concrete. Especially when the label is rotated. Only way I can view it as unambiguous is read the documentation for each part I come across.
Any chance of getting them to make the pin 1 mark less symmetrically placed on the package. Like closer to the side with the pin 1. I've always found it confusing how some manufacturers use two symmetrically placed indentations.
Pins always number anticlockwise from the top (because vacuum tubes number clockwise from the
base side). Never seen an exception to this, just remember it and the marking is unambiguous.
Right, and since this is an eight core processor we are going to need an octal socket?
Anyone remember the PLCC chips where pin 1 started in the centre of the top row?
There's always an exception to any rule, but my experience generally agrees with what Mark T posted when looking at the recent square packages for 44 & up pins. Not so much for the smaller dip packages though.
Anyone remember the PLCC chips where pin 1 started in the centre of the top row?
Of course, the 68HC11s I used many moons ago where in PLCCs. The 80C188 has the pin 1 in one corner though, probably was that before it got standardized, or directly from its LGA cousins
The centre 1 pin probably came about from a square die that was originally packaged in a dip. When you bond it out, you want to go from the top centre and anticlockwise to the bottom centre for the left side of the dip, then continue on the right bottom of the dip upwards to the top which finishes in the centre top of the die.
When just making Quad packages, then left corner probably makes more sense.
Comments
Pins always number anticlockwise from the top (because vacuum tubes number clockwise from the
base side). Never seen an exception to this, just remember it and the marking is unambiguous.
Besides how can you orient the chip wrong, there are only 4 ways to place a square chip!! So long as the
silk-screen has a blob in the right corner its foolproof.
Right, and since this is an eight core processor we are going to need an octal socket?
I see what you did there (notso) young man!
There's always an exception to any rule, but my experience generally agrees with what Mark T posted when looking at the recent square packages for 44 & up pins. Not so much for the smaller dip packages though.
When just making Quad packages, then left corner probably makes more sense.