Your right 0 digital inputs on the 6 and 12 model. Looks like you'd have to use the 18 unless there was a way to get creative.
We can't see other issues that could arise, e.g. let's say because of mounting, one needed 10 deg and 100 deg or -45 and +45 deg.
All I'm really advocating is a single device for the most part and it even does the servo power I believe.
With any design, there is still lots of other stuff like the case and weatherproof switches that have to be added.
This is a car environment and as long as the key works when it fails your still ok. Nothing mission critical. But because it's a automotive environment we have to treat it that way. A motorcycle environment is probably worse. It might mean that it could work for a year without problems and you do have to go back and add power protection or more robust power protection.
Transorb (TVS), fuse and reversed biased diode I think is where to start,
We can't see other issues that could arise, e.g. let's say because of mounting, one needed 10 deg and 100 deg or -45 and +45 deg.
All I'm really advocating is a single device for the most part and it even does the servo power I believe.
With any design, there is still lots of other stuff like the case and weatherproof switches that have to be added.
This is a car environment and as long as the key works when it fails your still ok. Nothing mission critical. But because it's a automotive environment we have to treat it that way. A motorcycle environment is probably worse. It might mean that it could work for a year without problems and you do have to go back and add power protection or more robust power protection.
Transorb (TVS), fuse and reversed biased diode I think is where to start,