This is just one way to do this, and it's pretty much as the data sheet explains. Lets get started.
PROJECT DETAILS:
What this is, is a simple Panel meter I had purchased from Circuit Specialists Inc - part number CX101BG. This meter can be used in a common ground situation, and costs roughly $14 or something like that.
My circuit is a PCB back pack to this meter that allows for the appropriate scaling resistors as well provides a method to switch between two different measurement ranges. This all works well enough... it's a little buggy, but I'm sure with some tweeting, finesse and gentle massage, it should run fine as a Chevy.
INs AND OUTs:
Inputs:
P7 - is the DC voltage input, there is provision for an LM7805 here, but this regulator can be bypassed if your circuit has +5V DC available already.
SW1 - This is were you would attach your range section switch. This controls a relay which will switch in the appropriate range resistors for the display range you would like.
PIN 11-13 - these are inputs for various decimal places. If you would like a decimal to be displayed, tie the desire pin high.
P6, P5 - Attach your circuit to be measured here P6+ P5-
Adjustments:
VR1, VR2 - these pots are tweekers for the two different measurement ranges. Again, this kinda works, it's hard to get it completely accurate, but it's close enough for me.
Resistance:
All resistance values depend on your individual need. The data sheet has a nice chart to help you decide what values to use. I have duplicated this chart in my schematic.
I think that is about it, I find this a simple to add a panel meter on the cheap to any project you might be thinking of.
Again, I welcome comments and suggestions... constructive criticism, etc. Please share this if you find it note worthy.
Thanks,
-Richard
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