Trying to make more progress on the MSP430/TLC59116F LED controller project I've post about in the past (http://forum.43oh.com/topic/5348-msp430tlc5940-based-led-sequencer/#entry46784)
I need to have 12V (~14.5V when running) DC to trigger the inputs for the various LED sequences. I know that the MSP430s I/O pins will not except 12V and I have to step it down.
Of the various choices I think an opto coupler would be best due to the electrical isolation but connecting it to the MSP has be a bit confused. Everything I've read has the uC controlling/switching something higher voltage and not the higher voltage coming in.
Do I need a transistor before the optocoupler? What about resistors, etc.
Sorry if this is all newbie stuff but I'm fairly new to digital circuits.
I think the 4N25 optocoupler should fit the bill but connecting it is where I'm confused.
Here's a shot of my lay out so far.
