openinverter forum

Hi everyone,

I am currently assembling / soldering the remaining components onto the VCU (Zombieverter) board and have a problem, I do not know how to orientate the gate drivers on the board.

The printing on the actual parts is "3122T HATL", but there is no dot or anything that gives an indication where Pin 1 is.
(there are three of these gate drivers to be soldered on IC27, 28 and 29. The BOM says these are FAN3122TMX-F085).

I searched on the Mouser homepage for the partnumber that Damien mentioned in his video, I end up with "On Semiconductor" or "Fairchild" as manufacturers, but these datasheets somehow do not match with the labeling of my parts, so I am not sure.


Any help?
this is a picture of the part, yet my ones say "3122T HATL".

If there is no dot then the bevelled/chamfered edge normally indicates the pin one side (not completely clear in the picture but it looks like the lower edge so pin one would be bottom left).

The fairchild data sheet shows both a dot and a bevel in the package drawing.

Hi Pete,

thanks for your answer. If you know what to look for you can indeed seen a chamfered edge on one side.
Would not have recognized that as an indicator, I was only looking for a dot...

Regards Stefan

The datasheet says there should be a pin 1 indicator, but it certainly appears to be missing.
The datasheet also says the beveled edge is on the same side as pin 1, so I believe Pete's answer above is correct.
The datasheet also says that pin 1 is on the bottom left with the text the right way up, so this seems to correlate with it being on the chamfered edge too.

I thought that the printed line also indicates the front / side of PIN 1.