I hope I am posting this in the correct area, if not, sorry in advance.
I am looking to create a very simple low power platform for a device I am working on, and I was trying to research and work through a number of technical questions I had regarding what I platform I should be developing for, and what types of parts I will need to order.
It seems that andruino has a very active enthusiast community, and therefore it makes it a very appealing platform to work with, however I have no idea about its power consumption relative to other devices. Is andruino the correct hardware platform to use in a extremely lower power situation, or are the better options available? If so, what are their drawbacks?
Since the device I am working with is relatively small, assuming that andruino is indeed the correct platform I should be developing for, I think I have decided to go with the mini pro 5v, as it will be easier to work with than a 3.3v system, will this decision negatively impact the overall battery life in some sort of dramatic way? (It will mainly be doing simple math, controlling a simple LCD display, and some graphical menus.)
Also I think I am going to need to communicate with 3 separate devices via a serial connection, on the mini pro will I need to use a multiplexer or something else to manage this? (I am relatively new to working with ICs and so some of this stuff still kind of confuses me.)
Thanks in advance to anyone who takes the time to reply to this, and I apologize if this is a rehash of a someone else’s previous post.
I’ve never used arduinos – I’m much more familiar with Microchip’s PIC lineup – so take this with a grain of salt.
There’s usually a pretty direct relationship between the supply voltage and the amount of current consumed: double the voltage, it’ll consume more than double the current. There’s also a relationship between clock speed and current consumed: double the clock speed, it’ll consume more than double the current. If your choices are between running a chip at 3.3V and 8MHz vs. running at 5V and 16MHz, you’ll see a real difference in power consumption. All else being equal, the 5V part might suck four times the power of the 3.3V part.
That’s a bit misleading, though. When designing low power systems, you want to leave the microcontroller in its low-power sleep modes as much as possible. When you run at a faster clock speed, you get more work done during the time your microcontroller is awake, so you get to sleep a greater percentage of the time.
As for chip selection, arduinos are probably the way I’d go if I were just getting my feet wet. They have a great community and nice development tools, and that makes a big difference. They aren’t the best in low power consumption, but they’re pretty good. Learning to take advantage of the microcontroller’s low-power modes will give you huge power savings. In comparison, switching to a lower-power chip like the MSP430 series would hardly seem to matter.
Even if the arduino only has one hardware serial port, you can fake as many as you want through software. Software UARTs have some limitations, but it’s probably a good way to start.