QFP44 adapter pinout

[Curtis_Newton]

Hi,

I ordered a socket adapter for an atmega32

so of course the wiring is all wrong (f@#§$!!!)
I want to try to make my own adapter board

but I cannot find any footprint that looks like this

is there something similar in kicad libraries ?

thanks

[hermit]

Sometimes you need to type less to find more.

[Curtis_Newton]

not at all, look at the picture
the idea is to make an adapter, I already found qfp44 footprint,
I need THE OTHER FOOTPRINT…I even spent time showing it with a red circle
I want to remake that board, the wiring is all wrong….I just don’t know the name of that through hole pinout

[hermit]

Are you saying you have a socket for the chip and THAT is through hole? Is there a data sheet for the socket?

[Curtis_Newton]

it’s a qfp44 socket (you can clamp the chip in it) they are pretty cool

but underneath it’s 44 pins…I thought it was standard…I just dont know the name of the pinout in the 1st screenshot

[paulvdh]

I did a little search for both tht and 44 and the closest that pops up is a PLCC socket:

Such ZIF sockets are quite rare, they are just made for test equipment, and just as with other connectors, different manufacturers likely have different locations for the pins in the footprint. I would not spend much time trying to search for footprint for something like this. Yamaichi seems to be quite popular, with lots of datasheets on the internet, but if you can’t find a datasheet, then making a picture of the thing combined with a ruler for scaling is a quite decent way of measuring pin locations for reverse-engineering. It’s just a few rows of pins, so there are not many measurements you need to make.

Can you buy those test sockets separate, without the PCB?
Desolding 44 pin THT devices is a nuisance, especially if you do not have a good desoldering pump.

Why not simply add an extra adapter PCB such as in

Source:
https://media.digikey.com/pdf/Data%20Sheets/Adafruit%20PDFs/1239_Web.pdf

Also:
For one-offs I usually do not bother to make a PCB, but hand-solder it on a piece of matrix board. Hand soldering one is about the same amount of effort as designing a PCB, and when you have a PCB you still have to solder the thing together.

[Curtis_Newton]

I de soldered the extra adapter to check the wiring , since it was missing some connections and the chinese atmega32 compatibility claim was …well …chinese

so I guess I’ll recreate the footprint from scratch

but how could I check the pin locations BEFORE sending it to a PCB manufacturer ?

[paulvdh]

If you don’t have a datasheet, then this is a reasonable method:

[tutorial] Test fitting Footprints

Hi everybody, not a question, but I just want to share how I test fit footprints. It’s a combination of a few things to make it work perfectly. The first step is to print a PCB mirrored on a piece of Paper: PcbNew -> File -> Print -> Options Mirror -> Print. 2nd step: Take a needle and pre-punch all the mounting holes into the paper. (For the large holes I used a hole punch). 3rd step: Carefully put the connector into the sheet of paper. 4th step: Take a picture or scan the whole contrap…

One thing I forgot to mention is the calibration of your printer.
If you make a printout for bigger parts, this may become a problem and it helps if you can calibrate your printer by figuring out separate scaling factors for the X and Y axis.

With a bit of luck, then Yamaichi makes 3D models available of their test sockets as .step files, and you can import it in Pcbnew and use the 3D viewer to see if it fits.

With the search below, there are quite a number of results that pop up:
https://html.duckduckgo.com/html?q=IC51-0444-467+yamaichi

Or search and/or mail the manufacturers website directly:
http://www.yamaichi.com/

Mouser apparently has some ECAD stuff available, and maybe you get lucky with sites like snapeda which has footprints for lots of weird footprints.

[rcfocus]

For reliable operation, I will suggest you to buy sockets form Japan makers. It is pretty easy to design the adaptor board in KiCad. Don’t be afraid of doing that.