[time-nuts] VCXO help

Chris Albertson albertson.chris at gmail.com
Fri Feb 25 20:20:04 UTC 2011


On Fri, Feb 25, 2011 at 11:02 AM, Tijd Dingen <tijddingen at yahoo.com> wrote:
> Hello Chris,
>
> No I didn't know SchmartBoards, thanks for the tip.
>
> Although maybe I am missing something... I just checked their site, and
> watched the videos, but I couldn't find anything I'd spend $12 on.
>
> When you say that it is "expensive at $12 each, but you need only one",
> do you mean that as "you only need to buy one gizmo once and you can
> reuse it to solder multiple different QFNs for several of you prototypes"?

No I meant one per project or one per chip

If you can solder these by hand to a PCB you don't need this.
"SchmartBoards" are for people who can't.  the little boards are just
breakout boards.  You solder the chip to the SchmartBoard and then
each lead goes to a larger through hole that is easier to use.
Basically it turns a QFN chip in to a part with .1" lead pitch.

Their innovation was to use a router to mill out the PCB so the chip
self-aligns and can't slide off the pads, so like I said you can
solder it with eyes closed.  The traces going to the pads are in
little trenches with fiber/epoxy walls between so you can't make a
solder bridge

The traces on the PCB are actually milled out trenches that are filled
with solder.  You place the chip in the board then place the solder
iron some distance from the chip and the solder in the trench melts.
 These are aimed at someone who wants to prototype with SMT components

Maybe you don't need this is you can hand solder QFN but hand
soldering BGA is hard and they have these for BGA too.

-- 
=====
Chris Albertson
Redondo Beach, California



More information about the time-nuts mailing list