I'm in quite a predicament, I can't seem to get the flip flop circuit that's part of my project to work.
Here's the overview:
Basically I have a weighing machine that tries to keep a water storage tank filled. once the tank gets to a certain emptiness, the filtration system kicks on until it is full, which shuts the system down until the tank is empty again.
I've gotten the load cell... amplification, and voltage comparator circuit to work. So, I do have 2 logical +5v signal going.
One signal is low while the system is below 5lb, and high the rest of the time.
The second is high unless the system is over 80lb.
They're both High while it is between 80 and 5lb.
So, I'm using 2 NAND gates to create just a simple flip flop circuit, so it will stay off until it gets below 5lb, and stay on until it gets above 80lb.
Unfortunately something that should be very simple I'd think, just doesn't seem to be working. Maybe I'm just being obtuse, but really I'm very new to electronics, so I'm probably just missing something. PLEASE, I need resistor values, tie up/down resistors etc. most the schematics I've seen just skip that part.
And just to re-iterate, this is a RS flipflop.
Here's some pictures to clarify.
I tried adding text, but it's not great... i hope it gets the point across, It's the front and back of the same chip.
Note I put one input into A, the other into C. Out 1 was connected to D, and Out 2 was connected to B. Ground to ground, Source to +5v.
Here's the datasheet:
http://www.chipcatalog.com/TI/CD40107BE.htm
Finally, on the outputs I'm getting .5v. Which is WAY too low to be right. What am I doing wrong?
Here's the overview:
Basically I have a weighing machine that tries to keep a water storage tank filled. once the tank gets to a certain emptiness, the filtration system kicks on until it is full, which shuts the system down until the tank is empty again.
I've gotten the load cell... amplification, and voltage comparator circuit to work. So, I do have 2 logical +5v signal going.
One signal is low while the system is below 5lb, and high the rest of the time.
The second is high unless the system is over 80lb.
They're both High while it is between 80 and 5lb.
So, I'm using 2 NAND gates to create just a simple flip flop circuit, so it will stay off until it gets below 5lb, and stay on until it gets above 80lb.
Unfortunately something that should be very simple I'd think, just doesn't seem to be working. Maybe I'm just being obtuse, but really I'm very new to electronics, so I'm probably just missing something. PLEASE, I need resistor values, tie up/down resistors etc. most the schematics I've seen just skip that part.
And just to re-iterate, this is a RS flipflop.
Here's some pictures to clarify.
I tried adding text, but it's not great... i hope it gets the point across, It's the front and back of the same chip.
Note I put one input into A, the other into C. Out 1 was connected to D, and Out 2 was connected to B. Ground to ground, Source to +5v.
Here's the datasheet:
http://www.chipcatalog.com/TI/CD40107BE.htm
Finally, on the outputs I'm getting .5v. Which is WAY too low to be right. What am I doing wrong?
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