So How Do I Find Pin 1 on the IC
Unfortunately, there is not a lot of standardization in the techniques by which chip makers help the builder identify pin 1 of an IC. However, there at least five rules of thumb that can help you get through 99% of the cases:
- Chamfering: if there is nothing identifiable on the chip, look for one edge of the chip to be
chamfered/bevelled with a 45 degree chamfer. When the chip is oriented with the chamfered edge
as the lower edge, then pin 1 is located at the lower left-hand corner of the chip:
- Notching: If there is a notch/scallop on one end of the chip, then pin 1 is found at
the lower left-hand corner of the chip when the chip is oriented with the notch on the left:
- Dimpling: If there is a round dot or "dimple" on the top of the case, then pin 1
is at the lower left-hand corner of the chip when the chip is oriented with the dimple/dot on the left:
- Striping: If there is strip or band on one end of the chip, then pin 1 is at the lower left-hand
corner of the chip when the chip is oriented such that the stripe/band is on the left:
- Lettering: if there is lettering on the chip then pin 1 will be at the lower left-hand corner of the
chip when the lettering is upright and readable: