Sign in

Not a member? | Forgot your Password?


Search avrclub

Search tips

Subscribe to avrclub

Free PDF Downloads

Advanced Linux Programming

What Every Programmer Should Know About Memory

Introduction to Embedded Systems

C++ Tutorial

Embedded Systems - Theory and Design Methodology

Microcontroller Programming and Interfacing

Introduction to Microcontrollers


More Free PDF Downloads

Discussion Groups

See Also

ElectronicsDSPFPGA

Find us on Facebook





Discussion Groups | AVRclub | Socket for ATmega128

Atmel AVR Microcontroller discussion group.

Socket for ATmega128 - acetoel - Feb 20 6:27:00 2003

Hello,
Is there any socket for the ATmega128? Where I can buy it?
Ezequiel




Re: Socket for ATmega128 - poitsplace - Feb 20 16:11:00 2003

--- In avrclub@avrc..., acetoel <no_reply@y...> wrote:
> Hello,
> Is there any socket for the ATmega128? Where I can buy it?
> Ezequiel

From what I've seen...sockets for TQFP packages cost a freaking
fortune. Just add connections for in-circuit programming to your
board. If you can make due with one of the 44pin PLCC chips, you
could get one of those with a socket. They're not actually that
difficult to solder on. The trick is to use a hobby knife to cut the
center piece of plastic out of the socket. It's not really very
functional on those chips. I found it's best to cut the little
plastic strips connecting the inner center square...just at the edge
of the inner square. Then bend the left-over plastic stubs back to
break them off. You'll be left with a socket that's RELATIVELY easy
to solder. When I made this...soldering was pretty easy

http://www.extremecooling.org/ec/modules.php?
name=Content&pa=showpage&pids

I just made sure to put some solder on the pads first and used a
little flux. However, after you solder it you need to test the
connections by trying to move each pin individually. If they can
move, you need to be resoldered. You can also identify unsoldered
pins by the sounds they make

BTW, those sockets are VERY unforgiving. If you put them down in the
wrong orientation you will NEVER get them back off again. If this
happens, you don't have to throw out the board. Just grab a hobby
knife and cut out the key (carefully, of course)



_____________________________
 Free pdf download: Advanced Linux Programming.


Re: Socket for ATmega128 - badpacket94501 - Feb 20 19:09:00 2003

--- In avrclub@avrc..., "poitsplace <lmburt@e...>"
<lmburt@e...> wrote:

Hey, how about some suggestions for newbies on what are the best
package types to buy our uControllers? I know some of them are
simply to small to solder with standard gear, however, what are some
of the easiest surface mounts to solder ?





Re: Socket for ATmega128 - poitsplace - Feb 20 21:06:00 2003

--- In avrclub@avrc..., "badpacket94501
<badpacket94501@y...>" <badpacket94501@y...> wrote:
> --- In avrclub@avrc..., "poitsplace <lmburt@e...>"
> <lmburt@e...> wrote:
>
> Hey, how about some suggestions for newbies on what are the best
> package types to buy our uControllers? I know some of them are
> simply to small to solder with standard gear, however, what are
some
> of the easiest surface mounts to solder ?

SOIC is the easiest. Twice as many pins per inch as a standard DIP,
and no hassles trying to get the solder to the pins. SOJ isn't bad,
but I don't think you can get any Atmel chips in that package (but
you can get SRAM in those). PLCC is good if you want it socketedd
(cause you sure as heck can't take off a PLCC chip easily)...read a
couple messages back for a tip on soldering the PLCC sockets down.

Of course, from Atmel's PDF's it seems that all their Quad Flat Pack
MCU's are the larger versions. They're only about 50% higher pin
density than SOIC chips...so it's still within a normal person's
abilities (although it's a real pain, I'm sure)

If you're buying surface mount resistors I'd suggest you go with 805
or 1206 sized parts

805 is pretty small...about .1 inches long (as wide as the standard
DIP pin spacing)

1206 is about .15 inches long and just a bit wider than 805

If for some reason you need to use bunches of resistors side by side
to connect to say...8 output lines on a SOIC latch...you'd need
something even smaller...a 603 sized resistor would work on that, but
it would be a real pain to work with.

BTW, don't think that just because I know the sizes that I have much
experience with this stuff.




_____________________________
 Free pdf download: What Every Programmer Should Know About Memory.


Re: Socket for ATmega128 - badpacket94501 - Feb 21 0:54:00 2003



Hey, thanks. I think I may start out with somethinglike the 2010's,
a little bit bigger. But, good tip about going smaller is I need
multiple side by side.

Now of course, how to find a hobbyists 'kit' that doesn't cost $50,
and give me 3000 resistors.....

Anyone know of a site that has a decent starter kit of resistors,
caps, etc? I am assuming buying them on an as needed basis would get
a litle expensive at Radio Shack?

Thanks again.




Re: Socket for ATmega128 - poitsplace - Feb 21 1:50:00 2003

> Hey, thanks. I think I may start out with somethinglike the
> 2010's,

I really would suggest you go with 1206's instead of 1210's. With
1206 sized resistors, you can space them at standard DIP spacing and
still run traces between. You'd be amazed how often something as
simple as running traces between pins can eliminate a world of
soldering (and a loads of board space) > Now of course, how to find a hobbyists 'kit' that doesn't cost
$50, and give me 3000 resistors.....
> Anyone know of a site that has a decent starter kit of resistors,
> caps, etc? I am assuming buying them on an as needed basis would
> get a litle expensive at Radio Shack?

You pretty much have to get them in bulk. I know
http://www.halted.com used to sell them, but they don't seem to have
a catalog any more so I can't quote you prices. You can also SMT
normal resistors. Just bend one side down and clip it off and bend
the other side down, then bend it back to horizontal after the bend.
That gives you a nice little handle to hold while you solder down the
first side. Then you can clip off the lead on the other side and
tack it down. If you surface mount LARGE components, you might want
to stick them down with a hot glue gun (or some sort of adhesive)
before you solder them on.




Re: Socket for ATmega128 - Patrick A. Timlin - Feb 21 11:53:00 2003

--- "poitsplace <lmburt@lmbu...>" <lmburt@lmbu...> wrote:
> PLCC is good if you want it socketedd
> (cause you sure as heck can't take off a PLCC chip easily)...read a
> couple messages back for a tip on soldering the PLCC sockets down.

You can buy thru hole mount PLCC sockets which are a no brainer to solder.
This is a nice alternative is you want thru hole for your prototyping (use
the socket) then move to surface mount later (just solder the PLCC chip down
directly to the board). =====
Patrick Timlin ptimlin@ptim...
http://www.geocities.com/ptimlin/

__________________________________________________




_____________________________
 Free pdf download: Advanced Linux Programming.


Hobbyist part kit (was:Socket for ATmega128) - Patrick A. Timlin - Feb 21 12:01:00 2003

--- "badpacket94501 <badpacket94501@badp...>" wrote:
> Now of course, how to find a hobbyists 'kit' that doesn't cost $50,
> and give me 3000 resistors.....
>
> Anyone know of a site that has a decent starter kit of resistors,
> caps, etc? I am assuming buying them on an as needed basis would get
> a litle expensive at Radio Shack?

You might try All Electronics Corp at http://www.allelectronics.com/

They have cool stuff for cheap. A standard 500 piece 1/4W resistor assortment
(thru hole parts) is values from 4.7 ohms to 10 Meg ohms with multiple (5, 10
or 20) pieces each of the more popular values) is $8.95US.

I don't see a capacitor assortment pack, but they have lots of different ones
you can pick and choose from. They do have an LED assortment pack (50 pieces,
$4US).

If you want, I can see what I have and maybe we can work out some sort of
trade (you send me an AVR chip or two assuming you have or will be buying
some, and I send you a care package of resistors, caps, sockets, LEDs,
headers, PCB connectors, crystals, etc.). Contact me offlist if you want to
see about working out some sort of trade. =====
Patrick Timlin ptimlin@ptim...
http://www.geocities.com/ptimlin/

__________________________________________________





Re: Socket for ATmega128 - acetoel - Feb 22 14:17:00 2003

Hi,
I know there are thru mount PLCC sockets, but the ATMega128 is
TQFP not PLCC. Can I use my ATMega128 with a PLCC socket? That's my
question. For all the ATMega64 and 128 users, in which kind of
socket they put their mmicro?
Thanks
Ezequiel

--- In avrclub@avrc..., "Patrick A. Timlin" <ptimlin@y...>
wrote:
> --- "poitsplace <lmburt@e...>" <lmburt@e...> wrote:
> > PLCC is good if you want it socketedd
> > (cause you sure as heck can't take off a PLCC chip
easily)...read a
> > couple messages back for a tip on soldering the PLCC sockets
down.
>
> You can buy thru hole mount PLCC sockets which are a no brainer to
solder.
> This is a nice alternative is you want thru hole for your
prototyping (use
> the socket) then move to surface mount later (just solder the PLCC
chip down
> directly to the board). > =====
> Patrick Timlin ptimlin@y...
> http://www.geocities.com/ptimlin/
>
> __________________________________________________
>




_____________________________
 Free pdf download: Introduction to Embedded Systems.


Re: Socket for ATmega128 - poitsplace - Feb 22 18:34:00 2003

Heh...they don't. You just have to make a board with in-circuit
programming. There is some good news about that though. First off,
Atmel uses the wider .8mm pin spacing for their chips...as I
mentioned before. Second...the forces at those scales actually work
in your favor. Just put some solder on the pads first then put a
little bit of paste flux down on the pads and solder down your chip.
If by chance you solder two or more pins together, just clean it up
with a desoldering braid.
I actually saw one article in which they used paste solder (that
mixture of flux/ground up solder) and just ran a bead of the solder
around all the contacts, put the chips on top...and put the whole
board in a toaster oven (and of course, it worked)

--- In avrclub@avrc..., acetoel <no_reply@y...> wrote:
> Hi,
> I know there are thru mount PLCC sockets, but the ATMega128 is
> TQFP not PLCC. Can I use my ATMega128 with a PLCC socket? That's my
> question. For all the ATMega64 and 128 users, in which kind of
> socket they put their mmicro?
> Thanks
> Ezequiel




Re: Socket for ATmega128 - acetoel - Feb 22 20:10:00 2003

Could you send the link to that article?
Thanks
Eze

--- In avrclub@avrc..., "poitsplace <lmburt@e...>"
<lmburt@e...> wrote:
> Heh...they don't. You just have to make a board with in-circuit
> programming. There is some good news about that though. First
off,
> Atmel uses the wider .8mm pin spacing for their chips...as I
> mentioned before. Second...the forces at those scales actually
work
> in your favor. Just put some solder on the pads first then put a
> little bit of paste flux down on the pads and solder down your
chip.
> If by chance you solder two or more pins together, just clean it
up
> with a desoldering braid.
> I actually saw one article in which they used paste solder (that
> mixture of flux/ground up solder) and just ran a bead of the
solder
> around all the contacts, put the chips on top...and put the whole
> board in a toaster oven (and of course, it worked)
>
> --- In avrclub@avrc..., acetoel <no_reply@y...> wrote:
> > Hi,
> > I know there are thru mount PLCC sockets, but the ATMega128
is
> > TQFP not PLCC. Can I use my ATMega128 with a PLCC socket? That's
my
> > question. For all the ATMega64 and 128 users, in which kind of
> > socket they put their mmicro?
> > Thanks
> > Ezequiel






Re: Socket for ATmega128 - poitsplace - Feb 23 1:16:00 2003

http://www.seattlerobotics.org/encoder/200006/oven_art.htm --- In avrclub@avrc..., acetoel <no_reply@y...> wrote:
> Could you send the link to that article?
> Thanks
> Eze