Lpc2000

Hi Joseph,

   To true. The real question is the LPC2138 one of those processors?
If so, then we may have to box it.

reagards,
Charles

--- In lpc2000@yahoogroups.com, "phlpcmicro" <joseph.goldburg@a...> wrote:
> 
> Hi Charles,
> 
> Thanks for the suggestions - all relivant details.... However some 
> cores do radiate abormally higher than others.
> 
> Using an RF probe and a spectrum analyser over the package you
> CAN see the difference in radiation levels of noisy cores.
> 
> Yes - there are methods to "sheild" noisy cores - but - why start 
> with one in the 1st place.
> 
> Philips did an app note 10~15years ago discussing the advantages of
> LQFP over DIP in relation to RF EMC radiaion characteristics.
> 
> Regards
> Joseph
> 
> --- In lpc2000@yahoogroups.com, "charlesgrenz" <charles.grenz@s...> 
> wrote:
> > 
> > Hello,
> > 
> >   I am currently in the middle of a design for the 2138. EMI is 
> very
> > important in the design. 
> > 
> >    Are you used multilayer boards? How about series resistors on 
> all
> > the lines (both input and output)? Do you have a resistor in series
> > with the XTAL2 output? How about 100pF capacitors on all the I/O 
> that
> > goes off the board. What crystal frequency are you using? How about
> > ferrites on all level transistion devices (like RS232 and such)?
> > 
> > Thanks
> > Charles
> > 
> > 
> > --- In lpc2000@yahoogroups.com, "tsvetanusunov" <tusunov@m...> 
> wrote:
> > > 
> > > > Some micro's have terible radiation characteristics and are 
> > > > unsuitable to in radio modems with sensitive analogue 
> frontends.
> > > > 
> > > > ARM controllers are used in mobile phones  etc.
> > > > 
> > > > What characteristics do the LPC2000 have that lend thenselves
> > > > radio modems / phones etc.
> > > 
> > > this is very interesting topic, I can't find any info on this in 
> LPC 
> > > datasheets, but we found interesting feature: when LPC PLL is 
> enabled 
> > > if you have near by (1-2 meters) FM radio you can hear the sweep 
> tone 
> > > for about second.
> > > Our QC found this as they have radio on their desk where LPC 
> boards 
> > > are tested, no one of other microcontrollers we used make such 
> > > interference to the radio.
> > > 
> > > Best regards
> > > Tsvetan
> > > ---
> > > PCB prototypes for $26 at http://run.to/pcb 
> > > (http://www.olimex.com/pcb)
> > > PCB any volume assembly (http://www.olimex.com/pcb/protoa.html)
> > > Development boards for ARM, AVR, PIC, and MSP430  
> > > (http://www.olimex.com/dev)