I am trying to find away to energize an automotive relay on varying voltage from 0-5V. I want to "fire" the NPN based on adjusting the pot.
This 0-5v is the 0-100% duty of a MAP sensor. I want to be able to make an adjustment so I can control when I want this to switch. Could be anywhere from 0v to its max range of 5v. By adjusting the pot, I want to be able to turn on the relay based on my desired levels.
So my thought was to have a adjustable voltage regualtor that has a range of 10v for adjusting. That is where I am a bit confused. Couldnt I just use a 7805, and make that adjustable with a pot for 0-5v? Then the comparator will feed its reference of anywhere from 0-5V, and by adjusting the pot, I can turn on or off the NPN.
It a nutshell, I want to be able to turn on the relay anywheres from 0v to 5v in a linear scale of 0-100%
Stu
This 0-5v is the 0-100% duty of a MAP sensor. I want to be able to make an adjustment so I can control when I want this to switch. Could be anywhere from 0v to its max range of 5v. By adjusting the pot, I want to be able to turn on the relay based on my desired levels.
So my thought was to have a adjustable voltage regualtor that has a range of 10v for adjusting. That is where I am a bit confused. Couldnt I just use a 7805, and make that adjustable with a pot for 0-5v? Then the comparator will feed its reference of anywhere from 0-5V, and by adjusting the pot, I can turn on or off the NPN.
It a nutshell, I want to be able to turn on the relay anywheres from 0v to 5v in a linear scale of 0-100%
Stu