thoughts on PSOCs?

Hi - I ran into PSOCs a little while ago - and I'm having trouble figuring 
out *what* exactly they are... Cypress calls it a "mixed signal array" - 
which is a term that I'm not very familiar with. They say it has a 
microcontroller, along with a number of configurable "elements" (that can 
be set to be ADCs, DAC, timers, PWM, etc.) But my understanding of a 
microcontroller is that it essentially is a microprocessor with a number of 
devices already built in - so what exactly is the difference here? Sorry - 
I'm sure this is a really simple question - I guess I'm just getting 
confused by the terminology. Regards,

-Michael Noone

> Hi - I ran into PSOCs a little while ago - and I'm having trouble
figuring
> out *what* exactly they are... Cypress calls it a "mixed signal
array" -
> which is a term that I'm not very familiar with. They say it has a

Basically they provide a way for you to make a mixed-signal ASIC in
small quantities, optionally flash-reconfigurable.

Example: someone I know is using one of these devices to replace an
EOLed ASIC that generates and decodes DTMF.

> be set to be ADCs, DAC, timers, PWM, etc.) But my understanding of a
> microcontroller is that it essentially is a microprocessor with a
number of
> devices already built in - so what exactly is the difference here?
Sorry -

A microcontroller has a fixed peripheral set. You can't affect the way
those peripherals are interconnected. In a pSOC you can (at burn time)
establish internal wiring between analog modules. You can also in some
cases choose pin to function mappings.
A pSOC is essentially an _analog_ FPGA.

"Michael Noone" <mnoone.uiuc.edu@127.0.0.1> wrote in message 
news:Xns95BBAA2B7B997mnooneuiucedu127001@204.127.204.17...
> Hi - I ran into PSOCs a little while ago - and I'm having trouble figuring
> out *what* exactly they are... Cypress calls it a "mixed signal array" -
> which is a term that I'm not very familiar with. They say it has a
> microcontroller, along with a number of configurable "elements" (that can
> be set to be ADCs, DAC, timers, PWM, etc.) But my understanding of a
> microcontroller is that it essentially is a microprocessor with a number 
> of
> devices already built in - so what exactly is the difference here? Sorry -
> I'm sure this is a really simple question - I guess I'm just getting
> confused by the terminology. Regards,

Conceptually, they are microcontrollers with a configurable array of 
analogue functions.

Leon 

Michael Noone wrote:

> Hi - I ran into PSOCs a little while ago - and I'm having trouble figuring
> out *what* exactly they are... Cypress calls it a "mixed signal array" -
> which is a term that I'm not very familiar with. They say it has a
> microcontroller, along with a number of configurable "elements" (that can
> be set to be ADCs, DAC, timers, PWM, etc.) But my understanding of a
> microcontroller is that it essentially is a microprocessor with a number of
> devices already built in - so what exactly is the difference here? Sorry -
> I'm sure this is a really simple question - I guess I'm just getting
> confused by the terminology. Regards,
>
> -Michael Noone

Both close but not quite.

You have a bunch of analog an digital "Blocks". They can be configured (or
reconfigured) at runtime.
It gives you flexibility to choose you own mix, or change it depending on what
you need at differt points in the program.
You can download the design kit.  Look at www.PSoCDesigner.com .
Not that it is not the perfect solution to every problem.  So make sure it
suits you need before starting.

Hi Michael,

Before embarking on PSoC just make sure you can live with the 
performance of the offered on-chip devices. Often available modules such 
as opamps are rather slow, have large offsets and sometimes common mode 
may not include ground.

So far I haven't been able to tolerate these kinds of limitations in any 
of my designs and ended up having 'to roll my own'.

Regards, Joerg

http://www.analogconsultants.com