Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
The pull-down resistor will pull down the 'high' voltage too, as well as the low voltage.
What you want may be, a transistor switch, that will turn Off completely when its input voltage or bias voltage across e.g. emitter-base (for an NPN base-emitter circuit) drops below 0.5 V or so.
Does that sound right?
What input voltage, for both positions of the lever, would the hall effect sensor produce by itself?
We can find something that will work, I am sure... but a pull-down resistor may not work well.
As I said, a transistor used as a switch on the output of the hall effect sensor, may be what you need. Its response to voltage levels would be non-linear, and hopefully act as a 'switch' that would turn Off altogether at a lower voltage level, but remain open, conducting voltage, at a somewhat higher voltage level.
This behavior of a transistor used as a switch is characteristic of proper biasing voltage.
If you tell me these three voltage values in the circuit:
1. the Vcc or + supply voltage
2. the voltage from the hall effect sensor when the lever is in one position (the higher voltage of the two, (2) and (3) here)
3. the voltage from the hall effect sensor when the lever is in the other position (the lower voltage)
I can give you a schematic showing how to get a low voltage from the transistor in one lever state or position, and a high voltage from it in the other position.
If your hall sensor will be given
+ 5 Vcc
and it will register when 'not sensing'
+ 5 V
and it will register when sensing
+ 2.5 V
then a transistor added to it will take care of the 'output' being
+ 4.75 or so
when not sensing
+ 0.8 V at most
Would that do?
Yes, a transistor switch would add an effective on/off function.
In other words, you want the circuit to go in an even progression from one voltage level to the next, depending on and matching the position of the lever?
As opposed to just switching 'On' and 'Off' - it should represent the position of the lever in the voltage level, right?
For linear response curves, you need solely linear components. A transistor circuit cannot give such linear response, transistors are non-linear components.
I never studied solely-non-linear circuit design... I know the components, I know the responses of those components, but the overall concept of not having active non-linear electronics involved is somewhat beyond me.
I suggest an array of resistors might produce what you need... but I'm not quite certain of even that.
With regrets, I have Opted Out, opening this case to other Experts in this category.