How to design a comparator?

[sisso]

Tell me how I could design a comparator that outputs only if voltage is 5 V.
Please tell me the chip no.'s that I should use for it and circuit digram for that.

 

[ericgibbs]

Tell me how I could design a comparator that outputs only if voltage is 5 V.
Please tell me the chip no.'s that I should use for it and circuit digram for that.

hi,
A low cost comparator is the LM393, get the datasheet, it shows example circuits.

try: www.datasheetarchive.com

 

[aljamri]

LM339 is a quad comparator IC, but you may need to read something like this


EDIT: ooops Eric is there, I'll quit quitly .

 

[Reloadron]

You also may want to give this a read. The link contains links to data sheets as well as detailed information as to the use of comparators.

Ron

 

[aljamri]

YES, that's what I was looking for, I've red that during my study and under stood the comparator operation. thanks Reloadron.

 

[ericgibbs]

hi aljamri,
Please, never say quit because of me.

Eric

 

[aljamri]

I am doing that whenever my teachers participate in a discussion

 

[dougy83]

Tell me how I could design a comparator that outputs only if voltage is 5 V.

So if 5V it outputs something and if <5V or >5V it outputs nothing? I would suggest you try a window comparator arrangement; this uses 2 comparators with slightly different references & the outputs joined together.

Please tell me the chip no.'s that I should use for it and circuit digram for that.

LM393 or LM339 will both do.

 

[sisso]

I want to create a device that reads 5V DC signal and convert it into binary signal. Then this binary signal is transferred to USB port of a PC and an application reads it.
Would the chip LM393 works for me upto the generation of binary signal?

 

[ericgibbs]

I want to create a device that reads 5V DC signal and convert it into binary signal. Then this binary signal is transferred to USB port of a PC and an application reads it.
Would the chip LM393 works for me upto the generation of binary signal?

A comparator will not do what you ask, you need analog to digital converter IC.

 

[sisso]

A comparator will not do what you ask, you need analog to digital converter IC.

Have a look on this fig.1, https://www.facstaff.bucknell.edu/mastascu/elessonshtml/Interfaces/ConvAD.html
is'nt this correct that a comparator can be called as 1-bit ADC.
Tell me the IC that will be needed for a ADC.

 

[ericgibbs]

Have a look on this fig.1, https://www.facstaff.bucknell.edu/mastascu/elessonshtml/Interfaces/ConvAD.html
is'nt this correct that a comparator can be called as 1-bit ADC.
Tell me the IC that will be needed for a ADC.

Its correct to say a comparators output can switch between 0 and 1 [ 0v and +5v], but its not true A2D converter.

How many bits to you require for the binary data, 4,8,12,16 or more.?

 

[sisso]

the least possible, I guess 4 is sufficient as I have to just detect the 5V voltage signal.
And does'nt require more precision.

 

[ericgibbs]

the least possible, I guess 4 is sufficient as I have to just detect the 5V voltage signal.
And does'nt require more precision.

If you just have to detect a 5V level, why do you state USB to a PC.?

Can you explain what you are planning to do.?

 

[sisso]

If you just have to detect a 5V level, why do you state USB to a PC.?

Can you explain what you are planning to do.?

I have a device that supplies 5 V signal each time a object passes through it, I want to detect this 5V signal through USB port of a PC and an application increments a variable each time it receives this signal. As a result this behaves as a counter. This is needed because later LPT port was available on systems on which pin 17 directly receives 5V signal and an application receives it. This is not possible with USB port. Thats why I need an ADC to convert this 5V to binary and this binary could be readed by USB port.

 

[ericgibbs]

I have a device that supplies 5 V signal each time a object passes through it, I want to detect this 5V signal through USB port of a PC and an application increments a variable each time it receives this signal. As a result this behaves as a counter. This is needed because later LPT port was available on systems on which pin 17 directly receives 5V signal and an application receives it. This is not possible with USB port. Thats why I need an ADC to convert this 5V to binary and this binary could be readed by USB port.

hi,
Its not possible to detect a 5V level on the PC's USB in the way you describe, it doesn't work in the same way as the parallel port.
Does your PC have a serial port.??

 

[sisso]

I have 18 Pin serial port on my PC but I am supposed to do this on USB port, this is a project given to me from my company. Also I am not supplying 5V directly to the USB port I am converting this 5V to binary from ADC then after that this binary to string of chars to transfer to the data pin of USB port.
Thats why I need an ADC to do that as I posted earlier. Suggest me how to make an ADC

 

[ericgibbs]

I have 18 Pin serial port on my PC but I am supposed to do this on USB port, this is a project given to me from my company. Also I am not supplying 5V directly to the USB port I am converting this 5V to binary from ADC then after that this binary to string of chars to transfer to the data pin of USB port.
Thats why I need an ADC to do that as I posted earlier. Suggest me how to make an ADC

The problem is that you need a 'device' between the A2D [ or comparator] and the PC's USB port.
The device can be specialised IC or a PIC controller that has a USB feature

The USB port requires the correct protocols to enable reading/writing to the PC's USB port.

 

[Reloadron]

Hi Eric

This link may be of some help.

This actually began several days ago. I would venture a guess he just needs a DI (Digital In) and some hardware to run it through. Anyway, the link may help a little.

Ron

 

[ericgibbs]

Hi Eric

This link may be of some help.
This actually began several days ago. I would venture a guess he just needs a DI (Digital In) and some hardware to run it through. Anyway, the link may help a little.

Ron

hi Ron,
Thanks for the heads up that another thread exists from the OP for the same topic.

As the previous thread and I have explained, he needs a specialised device, ie: at least the USB/RS232 adaptor or a PIC.