.... with the extreme "back to back" SMD placement of the antenna matching network, I have not yet had to implement coplanar design.
--- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@...> wrote:
>
> Design considerations:
>
> As this assembly process is targeted to the fabrication of very low powered 3/5volt microchips and their supporting SMDs, there are instances where in the final output stage, higher current carrying capacity wiring is required.
>
> The wiring (ultrasonic die bonding wires) used "inside" the microchip address this issue by doubling or tripling the bonding wires to the same connection.
>
> The simple addition of "solderable" insulated magnet wire for these higher current conductive paths are resolved (this is a very easy and minimal "manual" wiring requirement).
>
>
> In other RF microchips (ie: Bluetooth,WIFI,GSM,etc) "coplanar printed" transmission paths could be fabricated.
>
>
>
>
>
>
>
> --- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@> wrote:
> >
> > NOTE: The LAST thing you do is to release your completed epoxy potted module from the Corian@ "mold/carrier".
> >
> >
> > Should this assembly process prove competent, fabrication of extremely dense, multi-chip modules could be completed and working in around 4 hours(provided parts in hand and cad ready).
> >
> >
> > --- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@> wrote:
> > >
> > > It may even be possible to print both the conductive and insulating layers at the same time as they are from separate inkjets.
> > >
> > > This would cut the total "print/UV cure" time in halve!!
> > >
> > > --- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@> wrote:
> > > >
> > > > ...... screen printing "on top" of the "micro-adhesive: may be an even better solution.
> > > >
> > > >
> > > >
> > > > --- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@> wrote:
> > > > >
> > > > > Hi gnuv!
> > > > >
> > > > > On a blank 8.5"x11"x1/4" Corian@ substrate, print out your component layout screen (lets say that's a 2.5"x3.5" finished module size) in the center of this substrate.
> > > > >
> > > > > Apply double sided (releasable) "micro-adhesive" tape/film over your printed screen (its "micro thin" and "see through").
> > > > >
> > > > > Apply SMDs with a vacuum assisted "pick and place" probe.
> > > > >
> > > > > When finished, stack on top your substrate the 8.5"x11"x1/4" Corian@ potting mold (with the 2.5"x3.5" square hole in the middle).
> > > > >
> > > > > Epoxy Pot to top of mold. When cured, release potting mold from substrate, potting mold is then flipped over, and run through the modified printer for conductive and insulative inkjeting.
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > --- In Homebrew_PCBs@yahoogroups.com, "gnuvvekaavaali" <gnuvvekaavaali@> wrote:
> > > > > >
> > > > > > --- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@> wrote:
> > > > > > Something else I realized tonight, since the SMDs are "picked and placed" onto the "micro adhesive only"(no soldering) the SMDs can be placed "end to end" or "side to side" depending on the design of your schematic.
> > > > > > > >
> > > > > > > > For instance, 3 legs from my 64 pin QFN IC go to 6 capacitors, each leg going to two capacitors, then all caps go to vdd-.
> > > > > > > >
> > > > > > > > This normally would take 16 PCB tracks just to do this. By
> > > > > > > joining the SMDs "physically", soldered end to end without
> > > > > > > wires, from the top surface, I have now reduced my "printed
> > > > > > > wiring" down to just 4 connections. Similar printed wiring
> > > > > > > reductions are reflected throughout the entire assembly.
> > > > > >
> > > > > > Wow - very creative effort, indeed.
> > > > > > How do you ensure the accuracy of the SMD placement on the tape?
> > > > > >
> > > > >
> > > >
> > >
> >
>