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Noisy input sersor — Parallax Forums

Noisy input sersor

SiriSiri Posts: 220
edited 2007-10-26 01:47 in General Discussion
I am using a [url=mailto:BS@px]BS2px[/url] in my project.
The "pin 1" is connected to a pressure sensor via ADC.This part is working as intended - used to calculate the pressure at the sensor.
I am also using the sensor to trigger a solenoid when the pressure is >0.The problem is due to lack of hysteresis the solenoid swithes on and off very rapidly prior to settling down to either on or off position.I have tried with the help of forum members to increase hystersis but it still does not very smoothly.
I was thinking if it at all possible to use the Scmitt-Trigger built into the·SX chip can be used by:
· 1.connecting the out-put·of the pressure sensor·to "PIN 2" and also to "PIN 1"·so I can continue to read the
·· pressure.Then enabling the "Schmitt-Trigger" in "PIN2" to activate the solenoid - which then would·more·stable.
·2.The question is can I connect the same input from the pressure sensor to 2 input pins and use the independant of each other.

The pressure sensor sensetivity is from 0-5 inches pressure and is ratiometric to an out -put voltage of 0-4Volts.
So basically when the pressure sensor is activated the the solenoid is switched ·"on" and·"off" when sensor reads "0" or less

Thank you for your help

Siri

Comments

  • PJAllenPJAllen Banned Posts: 5,065
    edited 2007-10-26 01:47
    You could give that a try.

    You could program hysteresis, too.· For example,·if it engages at a value of x or >x, then it shouldn't release till·x-5 or x-15 -- something like that.
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