Lpc2000

Yes, that is one way of describing the core of a sigma-delta codec.

I'd agree with Owen on his observation about using DSP algorithms to 
reduce hardware requirements. We take this to the extreme, 
inplementing a full-blown software modem on the LPC2000. We've had 
customers who have replaced older 8-bit systems with 32-bit RISCs 
like the LPC2000 and actually reducing the system BOM cost, as they 
no longer need a modem IC. My point is that as well as having a much 
better programming environment (full ANSI 'C' etc.), more memory etc. 
you have a lot more processing power than any 8-bit, so why not use 
it?

To get back on-topic: does anyone know of a good (i.e. cheap!) way to 
interface an audio codec to any of the LPC2000 range? We've managed 
to do it without additional hardware for some voice-band (i.e. 8KHz 
sampling) codecs with a few tricks, but not for something with higher 
sampling rates (such as 44KHz and beyond). They tend to have 
something like I2S on their digital side, which doesn;t sit to well 
with the available interfaces.

Regards
Brendan

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Brendan Murphy, Chief Technical Officer (CTO)
Innovada, invent, DCU, Dublin 9, Ireland
Phone (DDI): +353 1 700 7522 Fax: +353  1 700 7545 Mobile: +353 87 
648 1741
E-Mail: brendan.murphy@...
Web: http://www.innovada.com
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--- In lpc2000@yahoogroups.com, Bruce Paterson <bruce@t...> wrote:
> Owen Mooney wrote:
> 
> > Some of the early CD players worked on this principal. They had a 
high 
> > freq 14 bit D/A. The advantage of this is the improved phase 
response of 
> > the system. Jo public couldn't understand how a 14 bit D/A was 
giving 16 
> > bit performance so I think they stopped doing it.
> 
> No, I believe the idea transformed to the extreme with MASH 1 bit 
> converters. Sample fast enough and you only need 1 bit (a single 
high 
> speed comparator). Isn't this what sigma-delta codecs use ?
> 
> -- 
> Cheers,
> Bruce
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