Is there a summary of package types somewhere?

Go To Last Post
9 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi,

There are tons of these:

VQFN (Punched)
VQFN (Sawn)
LQFP
TQFP
SOIC
TSSOP
TSOP
LGA 36
MLF
etc...

I will probably start with a STK500 and PDIP, but are any of these other packages considered "easy to deal with" in terms of finding reasonably priced sockets and ease of inserting/removing them ?

Thanks,

Alan

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Apart from PDIPs no other package is "easy to deal with".

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

PLCC in a pinned socket is relatively easy too.

SOIC is quite easy too on a DIY PCB.

Everything with a pin spacing less than 1.27mm is more difficult with DIY PCBs, and soldering is more difficult. Hand soldering a TQFP 144 with 0.5mm pin spacing on a pro made PCB is very doable though.

DFN/QFN/MLF are difficult to solder but can be done.

Truly problematic are BGAs.

Only DIP, PLCC and PGAs are really meant to be socketable too, for permanent service inside a widget.

There are sockets for SOIC/QFP/TQFP and maybe others but these are horrendously expensive, bulky and only meant for programming or testing purposes, not for anything else.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hi,

Thanks for the great overview.

Why do some AVR's like the USB ones only come in VQFN or TQFP? Would you try a quick home brew type project with something like these packages?

Thanks,

Alan

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

alank2 wrote:

There are tons of these:

VQFN (Punched)
VQFN (Sawn)
LQFP
TQFP
SOIC
TSSOP
TSOP
LGA 36
MLF
etc...

IPC-7351A
http://landpatterns.ipc.org/defa...

MLF packages:
http://www.amkor.com/go/packagin...

others like CASON etc:
http://www.amkor.com/go/packagin...

Quote:

are any of these other packages considered "easy to deal with" in terms of finding reasonably priced sockets and ease of inserting/removing them ?

The short answer is 'no'. Tests sockets exist, but you can buy a lot of chips and boards for the price of one of these test sockets.

http://www.ironwoodelectronics.com/
There are adapters, still get pricey. Not always a good idea electrically either.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

In addition to the replies so far (which I completely agree with), I would add that with a decent soldering iron, SOIC is extremely easy to solder. TQFP-64 is fairly easy without liquid flux, very easy with. TQFP-100 is actually easier to solder than TQFP-64 if you use liquid flux because the pin pitch does not easily allow solder bridges. QFN and DFN are more difficult, but you can solder them by applying some flux on both pcb pattern and package pads, then applying a small amount of solder to both sides, and finally using a hot-air station to reflow the solder (doesn't need to be too expensive).

For example, this one works great for me:
http://www.sparkfun.com/commerce...

A tool like this is *very* useful for soldering QFN, DFN, as well as removal of TQFP. I don't use all the special tips, just a round tip with app. 1/4 Inch diameter. For example, you can just move it in a semi-circular pattern around the part until the solder re-flows, and then pick it up with tweezers.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

alank2 wrote:
Hi,

Thanks for the great overview.

Why do some AVR's like the USB ones only come in VQFN or TQFP? Would you try a quick home brew type project with something like these packages?

Thanks,

Alan

I often make PCBs at home for fine-pitch devices like that, and don't have any problems.

Leon

Leon Heller G1HSM

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

alank2 wrote:
Why do some AVR's like the USB ones only come in VQFN or TQFP?
Because all semiconductor manufacturers target the professional market, not the hobbyist market. Most professional electronics development has moved away from through hole parts a long time ago. The money they make from one large professional customer is probably more than they make from all hobbyists together. DIL is becomming an exception, not the norm. If marketing decides the thing will sell well without a DIL package, it won't be put in a DIL package.

There is also a technical reason. DIL pin count is limited and bonding wire length is a greater problem. If engineering can't put it in a DIL package it won't be put in a DIL package (unless the boss insists, then ...).

alank2 wrote:
Would you try a quick home brew type project with something like these packages?
Why not? You at least have the following options:

- Lay out your own PCB. Manufacture it at home, or send it to some board house to get it done (there are cheap and there are expensive board houses)

- Buy an eval board, module board, or an adapter board with the IC already in place.

- Buy a blank adapter board and solder the IC in place by yourself

- There are some exotic techniques, where you wire such ICs with magnet wire. Here you see a master of such a technique http://elm-chan.org/docs/wire/wi... It takes years to get to that level. Mr. Chan's method is also special, because he wires the IC's in normal position, while most others who use this technique put them upside-down ("dead bug" wiring).

Stealing Proteus doesn't make you an engineer.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Quote:

- Buy a blank adapter board and solder the IC in place by yourself

For example:

http://www.futurlec.com/SMD_Adap...

Good quality and cheap.