How hot the hot end can get is not a function of the board's capabilities. The board is just interpreting what the thermistor is telling it and either turning on or off the heater. Each thermistor that gets configured has a lookup table that specifies that associates a range of resistance values with the corresponding temperature for that resistance. Want to have a hot end that can go to 900 degrees C? Just use a thermistor that's good to that temperature and create a table for it's values. Almost all thermistors that are readily available don't go that high though. Most are good for somewhere between 200-300 degrees C.Quote
Natas70
My question was basically asking what brands of boards are able to handle these hotends. It would be great if a Ramps board can handle the requirements to heat a hotend to 350 +
The metal oxides that are used for thermistors decrease resistance as temperature increases so as they reach higher and higher temperatures, resistance gets lower and lower until the resistance curve is essentially flat and not usable in an accurate manner. That's where thermocouples can come in as they don't change resistance values, they generate minute voltage readings as temperature increases. These voltage readings need to be amplified to be understood by the electronics which is why thermocouples aren't preferred for printers...it's something extra that needs to be purchased and isn't usually necessary.