Hi guys - would love your feedback on something.
As you know, we have successfully implemented full CHAdeMO control on Arduino Due and demonstrated charging of a number of vehicles from a number of sources. You also know that we are in the process of integrating all this into our chargers so that one does not have to have a separate CHAdeMO controller box. In doing so, we are realizing that a Due board as-is is quite an overkill. Also, ideally we would use the same MCU across all our products (JuiceBox, our DC chargers, CHAdeMO controllers, BMS, etc). But due to the size and cost of a Due, it is hard to integrate into some of those products.
So we are considering building our own board based on the same chip as Due (ATSAM3X8EA ARM with 512KB flash, 96KB RAM, etc). We would like to shoot for a form-factor similar to the Pro Mini or Teensy 3.x (https://www.pjrc.com/teensy/teensy31.html" onclick="window.open(this.href);return false
. I think this is possible if we...:
* Use LFBGA package of the same 144-lead chip: http://www.digikey.com/product-detail/en/ATSAM3X8EA-CU/ATSAM3X8EA-CU-ND/3128690" onclick="window.open(this.href);return false;
* break out the programming circuit based on ATmega16u2 into a separate board - we wouldn't actually design / build that one - we would just buy a programming adapter from someone like http://www.geeetech.com/iduino-due-pro-board-with-due-pro-usbserial-adapter-p-655.html" onclick="window.open(this.href);return false;. Note that these guys use a similar approach that I am proposing but their main board is still too big - largely because they are using LQFP package that is 5-6x the surface footprint and they have all the Due pins in connectors.
* limit the number of external pins to just ~45 vs ~90 on a Due. We would have: 8 ADC, 16 digital, 4 CAN, 6 UART, 4 SPI, 6-8 programming / power. Some of those could be done as pads on the bottom - Teensy-style.
What do you think? This would have ~1/8th of the footprint of a Due and would be completely indistinguishable from a Due to Arduino IDE. I think this could be an interesting board in its own right...
Valery