eStop Robotics CCI board

[eStop Robotics]

Mike,

Your 15k resistors will work fine.

There are two limitations on the resistor size to your resistor ladder question. The first is that there needs to be enough current for the A/D to get a correct value. The second is that there is not too much current draw that the CCI shuts down or overcurrents your USB port. With those two restrictions in mind, its actually harder to find resistor values that would do either of those things. So stay away from resistors that are lower than 10 ohms and higher than 1 M ohm. In other words with some margin, you want the current in your resistor ladder to be between 1 mA and 10 nA.

So with that in mind, and with plenty of margin, use any resistor values from 1k to 100k in your resistor ladder. You can use these resistors with a power rating of 1/8th watt or larger.

[taichichuan]

Originally Posted by eStop Robotics

Mike,

Your 15k resistors will work fine.

There are two limitations on the resistor size to your resistor ladder question. The first is that there needs to be enough current for the A/D to get a correct value. The second is that there is not too much current draw that the CCI shuts down or overcurrents your USB port. With those two restrictions in mind, its actually harder to find resistor values that would do either of those things. So stay away from resistors that are lower than 10 ohms and higher than 1 M ohm. In other words with some margin, you want the current in your resistor ladder to be between 1 mA and 10 nA.

So with that in mind, and with plenty of margin, use any resistor values from 1k to 100k in your resistor ladder. You can use these resistors with a power rating of 1/8th watt or larger.

Thanks for the response!

Mike