Lpc2000

----- Original Message ----- 
From: "skykotech" <rick@...>
To: <lpc2000@yahoogroups.com>
Sent: Friday, February 20, 2004 8:39 PM
Subject: [lpc2000] lpc2214 samples


> I just recieved 3 pieces of the LPC2214FBD144 (144 pin part) from
> philips as samples.  I was working on a rather complicated atmel
> AT91RM9200 design with all the bells and whistles, but since these
> parts arrived so quickly, I am considering putting that design on
> hold for a bit and getting something actually working by using the
> LPC2214.  Just to get something going, I am considering stripping my
> design down to the following:
>
> LPC2214FBD144
> 2 channel 16 bit DAC on SPI #1
> 8 channel 8 bit DAC on SPI #2
> 16 bit compact flash connector interface on the external memory
> controller
> RS485 level converter on UART0
> RS232 level converter on UART1
> output buffers for DACS (+/-10 volts on the 16 bit DACS, 0-5 volts on
> the 8 bit, unless I find a 8 channel 8 bit dac with 0-5 volt buffers
> built in)
> Simple linear voltage regulators
>
> To keep things as simple as possible, I will supply regulated 5V and
> +/- 12V externally, and use onboard 1.8v,3.3v,10v,-10v linear
> regulators.  I will bring out the rest of the IO to .1 inch headers,
> and also perhaps the address/data bus to .1 inch headers for
> experiments.
>
> Do you think this simple design is remotely possible on a 2 layer
> board?  I would love to keep it at two layers for cost reasons.


It should be possible, if you are reasonably skilled at doing PCB layouts. I
wouldn't use an autorouter, unless you have a really good (and expensive)
one like Specctra or Electra. You might need to go down to 6/6 mil design
rules, to keep the board a reasonable size, and use small vias. Use 0805 Rs
and Cs and put them on the back of the board. PCB-Pool can make double-sided
boards down to 6/6, with 0.3 mm holes for the vias, as standard. Not many
other low-cost suppliers can manage those parameters. Getting neat routing
to the connectors is likely to be the biggest problem, you will have a lot
of tracks to get in.

Four-layers would be *much* easier but about twice as expensive.

Leon
--
Leon Heller, G1HSM
Email: aqzf13@...
My low-cost Philips LPC210x ARM development system:
http://www.geocities.com/leon_heller/lpc2104.html