Quotewhy not go for switch mode regulator?I'd love to do that. Our assembler is currently checking availability and price on a couple of parts, including the EUP3410 and EUP3452A on this page: http://www.eutechmicro.com/PL_9_11_EN.htmlIf it turns out I can go switchmode for a minimal impact on BOM cost (and it fits!) I'll do it.--Jon
why not go for switch mode regulator?
Cool idea. I wouldn't populate it by default, but watch crystals are tiny so I should be able to bring out a couple of pads to solder the flying leads onto. I'll give that a go.
Yes, that was exactly it. Plus an interrupt connection from the W5100 to the ATmega so you wouldn't have to poll the chip to know if someone was connected there. The reason for that is that with a big memory chip like the 1280 or 2560, there is a lot more space to put in a webpage and act as a server and not a client. Although I believe that this is also in the Ethernet shields so should be here too....This would add bulk to the board as you would need a latch and a lot more vias going around, so you wouldn't have such a compact PCB as you do now. .
However, my priorities would be fitting with the Mega dimensions, having the proto area, and compatibility with existing library.
If it turns out I can go switchmode for a minimal impact on BOM cost (and it fits!) I'll do it.
two connections on the TOSC pins in the chip.
What external memory bus? Care to elaborate?
I did this as well, however I had solder bridges to isolate those two IO pins ("after" the XTAL) because I figured with shields attached there would be a high capacitance on the traces due to the long runs/headers/etc.
I can understand someone wanting this (and so many other add-ons seem to compete for SPI). However, my priorities would be fitting with the Mega dimensions, having the proto area, and compatibility with existing library.
True... I made a comment just to put the idea out there for someone with the skills and tools to make boards. Like Graynomad said it is also possible to create all this in a shield form factor, although that would create a very big mix-up for newbies that don't understand how the external memory bus works (although it could be minimized with working libraries).
and at 20V it would almost certainly go into thermal shutdown
Doesn't the ATmega2560 have a similar function for temperature like the ATmega328?