I recently created a board using the TC4429 symbol and its associated default footprint. I started assembling this board and noticed it is missing the hole for pin 6. Looking closer at the footprint in Kicad, I can see it says “missing pin 6” in the description.
Can anyone explain what I’m seeing here? Is this an error in the footprint or if there is a reason why pin 6 is omitted for this chip? The TC4429 that I have does indeed have 8 legs. Footprint is “Package_DIP:DIP-8-N6_W7.62mm”
Some of those IC’s do indeed have a missing pin, and this is on purpose. For example the “TNY” series of SMPS IC’s have a high voltage (300V+ ) input , and therefore pin 6 is removed to increase the clearance.
The “N6” in your footprint name means that there is No pin 6.
You should have used the footprint without that part. 
N6 means No Pin6
N7 means No Pin7
You want DIP-8_W7.62mm
I see we answered at same time…
Ah, looks like this will be a practice batch. Thank you
I am also wondering why you did not catch this before sending out gerbers. Do you use ERC and DRC? Especially if you used that pin 6 in your design, it must have complained about it. And the missing pin should have been pretty obvious during routing of the PCB too.
In addition, it’s useful to set up a checklist of things to check before sending out gerbers for manufacturing.
It’s always good practice to check the footprint against the devices datasheet.
Kind of a standard practice here is to maintain a personal library of all parts you use AND VERIFY. That way in the future you don’t have to go through the verification step again.
On small projects it isn’t a bad idea to acquire the parts and check them against the design. If you are shopping for generic replacements this is kind of a ‘must’ if you don’t have the datasheets. Sometimes the supplier might be selling a generic without a proper link to the correct data sheet.
This is especially important for USB sockets and D-type connectors which seem to have a huge range of variation
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