I was asked to post this for a buddy, but it is serious money, if the quote
is accepted. Please reply offlist to me? Thank you!

Basically, he wants to find an ready to roll CAN bus project with EVERYTHING
needed to read a few sensors in a car, do some processing on those reading
with some microcontroller (PIC? MSP430? AVR? Whatever) and then post out
messages to some device on the bus that will do something with the
information. Yeah... not a great spec, but the point is to just find a
development system that already has the standard stuff in it for working
with things you find in a car so we don't have to burn all the cycles
required to come up to speed on it.

Here are the details we have so far:

PROJECT #1:  Automotive Sensor System  (HOT!--RFQ response due this 
coming Monday, Product by mid-March)

Basic requirements are for an automotive environment (with ALL that 
implies for temperature, shock, vibration, MTBF, etc.!) sensor/signal 
conditioner/CAN transceiver module.  We already have the sensor suite 
and signal conditioners as COTS products which will require minimal 
modification.  We are looking for a recommended chip set and 
benchmark design that provides the ADC and CAN interface and 
processor.  The sensor suite will provide several (typically 2, but 
potentially up to 8) analog signals which will need to be digitized, 
and processed through a 2-3 element polynomial equation to generate a 
temperature compensated and linearized output value for each 
sensor.  It may also be possible to move the processing to the 
control module and merely report measured values if there are 
significant savings in cost or space. Overall accuracy can be met 
with a 12-bit ADC, although higher resolution is MUCH preferred.

Although we have not yet seen the customer's CAN specification, it is 
believed to meet normal American and European automotive 
requirements, and have a relatively simple command/response 
set.  Evenutally the system will require EU, CE, FCC, and other 
approvals.  ROHS is also required.

Power availability is not an issue, although there is an overall 
limit to about 2-5 watts, and a very clean power bus is 
anticipated.  HOWEVER, there is a requirement for operation in a 
Class-I, Div-1 or Div-2 explosive environment.  i.e. intrinsic safety 
is mandatory, which implies low voltage and low power requirements, 
along with high immunity to EMI, ESD, and gross over-voltage 
conditions.  Energy storage devices such as inductors and capacitors 
must be minimized almost to the point of non-existence compared to 
normal consumer applications, which can create issues for 
bypassing  and filtering electronic noise ;-).

Full galvanic isolation of the sensors and processor from the CAN bus 
may be an additional requirement imposed by the sensors.  There are 
several good digital isolation solutions available, and we do not 
anticipate problems here.

Although this requirement is being driven by a specific customer, we 
want to end up with a "generic" system that can be easily adapted to 
different sensor suites and applications in the future.


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