Hi All, A little background
I have a version of arduino named PRO MINI which has very few components present. I think it has the bare minimum components an atmega MC needs to operate. I am not using FTDI but using an arduino UNO board to program this pro mini.
My project
I have plans to embed arduino pro mini inside one of my modded home appliance and this pro mini will control an LCD displaying information about my appliance. My questions are:
Q1> Is pro mini a reliable board for this purpose? Is it suitable for long running applications? My appliance is running all the time(24/7).
Q2> Would I need a fan to cool down the microcontroller chip so that it works normally and longer?
Q3> Any other suggestions or inputs will be appreciated.
In principle, I think the Pro Mini should be just fine - the MCU in there is a well-known model and there's no reason for it to overheat under normal, according-to-specs conditions.
However, there are some very cheap Pro Mini clones out there from the far east, and one can only assume there is a reason for this cheap price. Perhaps substandard components, perhaps questionable workmanship... perhaps not.
An important guiding question here is where exactly you're going to use it, and what will happen if it fails while unattended.
You are right- the Pro Mini is the "minimal" board for an "end" application - one where you just want it to perform a task without connection to a computer. It is generally as or more reliable than any other board. There is a small chance of getting a dodgy item but most of us have had excellent results from vendors such as "Alice" - TxHang or DealExtreme.
It has been mentioned that you need a reliable power supply for reliable operation. If you want more informed opinion, you need to explain exactly what domestic device you have in mind. A kettle is probably not suitable. You do not need a fan to cool the MCU unless you already need a fan to cool the appliance itself.
I am going to place this on inside a solar charge controller + DC/AC inverter. I am thinking of replacing the LEDs in the display panel with 16x2 LCD. That 16x2 LCD will be controlled by this PRO mini.
The PCB has a few pins that go straight and lit up a few LEDs. I will connect the pro mini to read this Pin;s signal and display an informative text message on the LCD. So all I need from the Pro mini and LCD duo is displaying the text message.
I selected the Pro mini because of its cheap price. Space is not a constraint for me, if there is a bigger/another model of arduino(with min components and hence economic) I can use that too. Please suggest.