[See attached diagram]
I'm trying to design a circuit that connects to the input terminals of the noninverting input of this comparator circuit such that:
-The input to my circuit consists of a SPST switch and a 9 volt battery
-When the switch is thrown on, there would be a 10 second delay before the LED turns on
-When the switch is thrown off, there would be a 4 second delay before the LED turns off
Op-amps, RC circuit time constants
The Attempt at a Solution
So obviously I'm trying to use some configuration of capacitors and resistors to achieve the proper time constant to fit the specifications of the question. However, I've been messing around with this for awhile now to no avail.
The noninverting input can be set to anything between 1.5-9V.
I think it needs to involve a 330uF capacitor.
I'm not sure how I'm going to achieve two different times using the same component values (and thus same time constant?)
I tried connecting a 28k resistor in series with the voltage source (& switch) to the non-inverting input, with the 330uF capacitor connected between the input and ground, and the inverting voltage set to 6.1v but this configuration of components is not giving me the desired response.
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