Lpc2000

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)