I have been trying to build a circuit for days now on a circuit simulator program, and I have not been able to make it do what I want.
This is a 12V circuit. Control input is a variable resistance between 1KΩ and 10KΩ. Output is a SPST relay.
I want independently adjustable on and off trigger points based on the resistance value of my control input. I want the relay to trigger on when control input resistance exceeds a set limit (limit controlled by a trimpot), and the relay to trigger off when control input resistance falls below another set limit (limit controlled by another trimpot). The off trigger point must always be lower than the on trigger point.
As an example, if the on trigger is set at 5kΩ, and the off trigger is set at 3kΩ, when the control input resistance exceeds 5kΩ, the relay turns on, but will not turn off until the control input resistance drops below 3kΩ.
I can do this with a micro controller easily, and the program logic may help others understand what I am trying to accomplish; "if input 1>5k then output 1 = high; if input 1<3k then output 1 = low". I am trying to avoid a micro controller, because this seems like it would be a very simple circuit, I just cannot seem to get the correct combination to make it happen.
Any help would be greatly appreciated.
This is a 12V circuit. Control input is a variable resistance between 1KΩ and 10KΩ. Output is a SPST relay.
I want independently adjustable on and off trigger points based on the resistance value of my control input. I want the relay to trigger on when control input resistance exceeds a set limit (limit controlled by a trimpot), and the relay to trigger off when control input resistance falls below another set limit (limit controlled by another trimpot). The off trigger point must always be lower than the on trigger point.
As an example, if the on trigger is set at 5kΩ, and the off trigger is set at 3kΩ, when the control input resistance exceeds 5kΩ, the relay turns on, but will not turn off until the control input resistance drops below 3kΩ.
I can do this with a micro controller easily, and the program logic may help others understand what I am trying to accomplish; "if input 1>5k then output 1 = high; if input 1<3k then output 1 = low". I am trying to avoid a micro controller, because this seems like it would be a very simple circuit, I just cannot seem to get the correct combination to make it happen.
Any help would be greatly appreciated.