7 segment 3 digit Temp Display? Arduino mini

Hi there,

I'm working on a project to display the temperature of a thermocouple (I ordered the amplifier already) on a 3 digit 7 segment display, but I've never done it and I cant make much sense of what there is on the internet.

Ideally I would like to use an arduino mini or nano (I already have a mini). Also, I have a segment like this

Here is a picture of what I intend to do:

I want to set a temperature and once the thermocouple reaches the temperature the servo moves.

I've done arduino projects before but I'm an ME not a EE so please bear with my simple questions.

Thanks in advance for the guidance

Rather than use the display that you linked to, I think that it would be far more cost effective to use a ready built LCD shield. Using a shield obviously precludes you from using an Arduino mini or nano.

I think that you need to do a cost benefit analysis to work out whether it is better to use the components that you already have, plus say a whole week of work to integrate the system, or get items that are more plug and play, and have a working solution in an hour or two.

You will probably want to use some sort of driver for that display - you could co it with individual lines, but it will need a [u[lot[/u] of pins! I prefer to use something like this 4 digit display from adafruit. It’s more expensive, but only needs four wires, and is super easy to program, since it uses I2C.

JohnLincoln, I hear you about the LCD, but I just don’t like the way those look. Bad memories from the 1980s I guess.

I'd say that since you've already got a mini and the display, you can use those.
To drive the display you need 11 Mini pins, 8 current limiting resistors and 3 transistors. The display is a common anode type so you need to multiplex it. To display a number on digit 1, set the appropriate segment pins low (these are cathodes) then set the pin to switch on the transistor which drives the anode of digit 1. Repeat this cycle continuously for all 3 digits. Do it fast enough and it appears that all 3 digits are lit simultaneously.
As has been said already, there are simpler ready made solutions, but you'll learn something if you do it all your self.

ChrisTenone:
I prefer to use something like this 4 digit display from adafruit.

Great Idea. I think that's the way to go. I just ordered a similar one from ebay.

JohnLincoln:
Using a shield obviously precludes you from using an Arduino mini or nano.

I have a size constrain that does not allow me to use the uno. The nano at most.

I'll report back once I get the parts. Thanks a lot