Hello - I'm looking for a small microcontroller that has an onboard CAN controller. If it also had an onboard CAN transciever that would be great - but I've yet to see that in any microcontroller so I'm not getting my hopes up. The problem I've run into is that I'm working on a very small board that needs a CAN interface. Right now I'm planning on using an Atmel AT90CAN128 but I'm early enough in the design stage that I could switch to something else. The problem with the AT90CAN128 is it's size and availalble packages - it comes in a TQFP 64 and a QFN 64. The TQFP is 16mm across which means it's almost as wide as the board it is destined to be on. Not an ideal situation by any means! The QFN is a much more reasonable 9mm across, but the pad on the bottom presents problems in soldering prototypes, and, more importantly, makes routing very difficult as traces can't be routed beneath the chip on the top layer of the board. Unfortunately the QFN is looking like the best option right now as I just don't think I can free up enough space for the TQFP.
I have looked at the offerings of Philips, TI, and Microchip - and the best I could find was the Microchip PIC18F2480 in a QFN 28 package. But I am not particuarly fond of the idea of using a PIC as I understand there are no good open source/free C compilers for it, and again that chip suffers from a QFN package (though a smaller QFN like this QFN 28 would help with layouts). I also have never used a PIC, so there would be the initial learning curve to get over.
My question is this: Are there any smaller microcontrollers that have onboard CAN controllers? Ideally Atmel would start making an "AT90CAN48" (an ATMEGA48 with CAN). To me a chip like this would make such great sense for so many applications that I just don't understand why it isn't on the market yet as there are no other chips with CAN in that price bracket, to the best of my knowledge.
Thanks for your help,