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Subject: Re: Flip n' Print ? (concept proposal for development)

From: "Richard" <richard.liberatoscioli@...>
Date: 2010-05-26

.... THIS CD PCB ADAPTER HAS NOW BEEN TAKEN

Thank-you!


--- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@...> wrote:
>
> NOTE:
>
> I have the special metal CD insert for making 2.5" by 3.5" conventional circuit boards made by Full Spectrum Engineering.
>
> You can read about it here:
> http://www.fullspectrumengineering.com/pcbinkjet.html
>
> Its yours for the asking (FREE) ....just drop me an e-mail or Yahoo IM
>
>
>
>
>
> --- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@> wrote:
> >
> >
> >
> >
> >
> > ..... an example of the conductive traces "reduction" ratio:
> >
> > 64 pin leadless QFN RFID GEN2 UHF Reader IC with all required SMDs connected (res,caps,inductors,x-tal,etc.)
> >
> > Conventional multi-layer "PCB" verses "Flip n' Print"
> >
> > 16 traces reduced to 4
> > 5 traces reduced to 2
> > 5 traces reduced to 2
> > 14 traces reduced to 3
> > 5 traces reduced to 2
> > 23 traces reduced to 10
> > 7 traces reduced to 4
> > 5 traces reduced to 2
> > 6 traces reduced to 3
> > 8 traces reduced to 3
> > 5 traces reduced to 2
> > 6 traces reduced to 3
> > 5 traces reduced to 2
> >
> > Totals:
> > 110 traces reduced to 41
> >
> > Instead of a 5 or 6 layer conventional "PCB" (1.5" by 3/4") only 2 or 3 "printed layers" are needed.
> >
> > By placing the SMDs "end to end" and "side by side" in combinations, for these connections, you afford essentially a zero "resistive loss",zero "stray inductance and capacitance" and highly conductive soldered connections.
> >
> > With the now greatly reduced physical length of the "inkjetted conductive traces"(most are only 1/8" to 1/16" long), the higher resistance of the conductive inks now becomes negligible.
> >
> > In essence, this assembly method uses the SMDs themselves as the majorty of the "wire traces" required.
> >
> >
> >
> >
> > --- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@> wrote:
> > >
> > >
> > > Hello Homebrew Printed Circuit Group!
> > >
> > > I have successfully modded my Epson Artisan 50 printer Epson Printer
> > > Mod
> > > <http://groups.yahoo.com/group/Inkjet_PCB_Construction/photos/album/1664\
> > > 97487/pic/list> to make PCB boards. I did this, as I'm sure as all in
> > > this forum, want to quickly build working devices from all the many
> > > awesome microchips out there (ie: MCU, RFID,WIFI,GSP, etc.)
> > >
> > > In my current project, I need to fabricate a "system-in-package" (SIP)
> > > module containing an RFID reader chip (QFN), MCU chip and WIFI
> > > chip(QFN) on two PCB's (1 1/4" x 3/4") including the required discrete
> > > SMD's (resistors, capacitors, inductors, x-tal, etc).
> > >
> > > This project requires very small SMD's and a very small and dense
> > > multi-layer PCB with micro vias for fabrication.
> > >
> > > This project well exceeds my existing "Homebrew" equipment capability to
> > > fabricate this module.
> > >
> > > In assessing the demands for the size and scope of this project (for a
> > > "homebrew" solution) the "show stopper" was all in the fabrication of
> > > the PCB itself.
> > >
> > > Here I began my quest for a different "homebrew" solution.
> > >
> > > Could I build this module without the complex multi-layer PCB?
> > >
> > > Could I interconnect all SMD's (IC's and discrete's) without soldering?
> > >
> > >
> > >
> > > Concept proposal:
> > >
> > > Start with a blank substrate (metal, glass, FR4,ceramic,etc) in place of
> > > a conventional PCB.
> > >
> > > Apply double sided releasable 3M "micro adhesive" tape covering the top
> > > surface of the substrate.
> > >
> > > "Pick and Place" all SMD's onto the top surface of the substrate. Note:
> > > with no PCB traces or vias to contend with, a 50% reduction in SMD
> > > spacing is obtained.
> > >
> > > "Epoxy Pot" the top surface embedding all the SMD's.
> > >
> > > Flip over the substrate (now working from the bottom side) and release
> > > the tape and substrate from the potted assembly. Clean off any residual
> > > adhesive.
> > >
> > > At this point, you should see only the exposed metal contacts of all the
> > > SMD's.
> > >
> > > Using the modified Epson Artisan 50 printer (set head height to pass the
> > > 1/8" thick epoxy pot assembly depth) and print with special UV curable
> > > conductive ink (MetalonĀ®)
> > >
> > > UV cure (need to build a "homebrew" UV source for curing the conductive
> > > ink). The commercial version does it in 3 or 4 seconds.
> > >
> > > Subsequent conductive traces (emulating the multi-layers of a
> > > conventional PCB) are first "masked out" by printing with a different
> > > inkjet of NON-conducting ink at the conductive trace crossovers.
> > >
> > > DONE! : )
> > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
>