Hello
I would like to built a 18F97J60 board, but this Pic is TQFT 100 package and not easy to solder on a home made board without special SMT tools. ( too thin pins )
Is there some adaptors available on the market for this package, or maybe a way build home made board with that Pic ?
Your experience will be much appreciated,
TQFP can be soldered by hand, spark fun has a great SMD soldering tutorial in their tutorials section.
We solder 208 pin PQFP with fine pitch by using a hot air rework machine where I work, we’ve soldered 144 pin TQFP’s by hand with a fine tip solder iron on occasion.
You don’t even need a fine-tipped soldering iron, any iron will do. You just need solder and desoldering braid. Flux helps. A good magnifying glass or microscope is almost essential.
Apply flux. Position the chip correctly (the hard part). Using two pairs of tweezers and some kind of hands-free magnifying device is the best way. Optionally tack one corner pin down with solder. Cover one whole row of pins with lots o’ solder. Repeat for the other 4 rows, then use braid to remove it, leaving a nicely soldered chip! Inspect with the magnifying glass for shorts and open pins (poke each pin with tweezers, if it moves it’s not soldered).
On the other hand, removing a TQFP without hot air or IR is very difficult.
Removing chips is very easy with ChipQuik.
Leon
Ok for soldering method, but how should i get a PCB with such thin wires without PCB machine ?
is it possible to make it at home ?
I often make home PCBs but with regular components, not SMT …
I don’t have a problem making PCBs for fine-pitch devices.
Leon
You must be very experienced, i guess UV exposition must be well calculated, isn’t it ?
is there 100% fully working method to succeed with thin PCB wires ?
there are a number of web sites that can take you through making PCBs at home. There are two ways people use:
photo exposure
toner transfer
photo will get you finer lines and I know people have done QFNs that way. Toner transfer is a bit harder to get to work for fine pitch but it is possible.
I suggest you use google…
Once the process is optimised it works every time.
Leon
I use toner transfer for home made PCBs.
Here is a picture of a breakout board I made for a TQFP-100:
http://spectrum.alioth.net/doc/images/2 … eakout.jpg
The decoupling capacitors are 0603 size, also hand soldered.
This a very good board,
would you please accept to share the PCB template ?
winston:
I use toner transfer for home made PCBs.Here is a picture of a breakout board I made for a TQFP-100:
http://spectrum.alioth.net/doc/images/2 … eakout.jpg
The decoupling capacitors are 0603 size, also hand soldered.
Nice work Winston. Xilinx says to use 4 layer boards but your’s is obviously 2 layer (at most). Have you had any problems from that?
Also, thought I’d jump in here to note something I’ve had lots of success with. If you’d rather spend the $5 on a complete breakout board with soldermask and a ground plane, instead of copper clad, toner transfers, and etching chemicals, I’ve had a lot of luck with Schmartboards:
They have boards for many parts in many pitches, and have even started making BGA breakouts recently. I have used their normal, cheaper boards (not the EZ ones) with a little bit of solder paste, and it works like a dream.
CPLDs will generally work OK on single-sided boards. I often use them on similar home-made PCBs. It depends on the speed and what is on the outputs.
Leon
Thank you very much silic0re for this link.
It is exactly what i’m looking for .
However, board cost about 9$ and shipping cost ~ 75 $ for France !
Is there a cheaper place to order ?
For now, i need to find a hand soldering method for SMT
What will you suggest me to get best results : iron, if so which one ?
or maybe hot air station ( much expensive )
Many thanks for your experience,
Drag-soldering works very well. I use a Metcal system with a mini-hoof cartridge, but you can use an ordinary tip.
Leon
Thank you very much silic0re for this link.
It is exactly what i’m looking for .
However, board cost about 9$ and shipping cost ~ 75 $ for France !
Is there a cheaper place to order ?
There are distributors ( http://www.schmartboard.com/index.asp?page=products_buy ) all over the place, including France ( http://www.lextronic.fr/R516-ci-en-boitier-qfptqfp.html ).
leon_heller:
Drag-soldering works very well. I use a Metcal system with a mini-hoof cartridge, but you can use an ordinary tip.Leon
Yup - no need for hot air. I wouldn’t use a $5 soldering pencil but any decent quality soldering iron will work fine. You don’t need an expensive tool. There’s a video floating around the internet of someone using a huge soldering iron doing some sort of TQFP. The tip must be an inch (er, 25.4 mm) across.
You will also want to use liquid flux - it really helps.
Don’t forget solder wick. It cures many errors.
Weller makes nice irons.
So does [[OKI (Formerly Metcal)](http://tinyurl.com/49yj26).henryhallam:
Weller makes nice irons.
A Weller WTCP and Metcal sit side by side on my bench.
I’ve had good success while using a heatshrink
[hot air gun as a poor-person’s rework station.](http://tinyurl.com/3uk2qo)](http://tinyurl.com/49yj26)
