Hello everyone my name is Matt, I'm a new member. This is my first post, on this or any other forum for that matter, so please bear with me while I get the hang of this. I must say this is great having a place to come & ask questions of people who are obviously much more experienced and knowledgeable in the field of Electronics than myself. Okay, enough with the rambling and onto my question. I am currently building a magnetic levitator using IR sensors. The electrical diagram that I found online Show 2 op amps drawn on the schematics. In parentheses beside the first op amp it states... (both op amps are one TLO72) . I know that sounds pretty self-explanatory, but to be sure... that does mean he's actually using a single op amp and only shown as two on the schematics in order to make it easier to understand where everything connects.... is that correct?
Thanks in advance for taking the time to answer this question

 

A TL072 is two op amps in a single package.

Bob

 

Hello everyone my name is Matt, I'm a new member. This is my first post, on this or any other forum for that matter, so please bear with me while I get the hang of this. I must say this is great having a place to come & ask questions of people who are obviously much more experienced and knowledgeable in the field of Electronics than myself. Okay, enough with the rambling and onto my question. I am currently building a magnetic levitator using IR sensors. The electrical diagram that I found online Show 2 op amps drawn on the schematics. In parentheses beside the first op amp it states... (both op amps are one TLO72) . I know that sounds pretty self-explanatory, but to be sure... that does mean he's actually using a single op amp and only shown as two on the schematics in order to make it easier to understand where everything connects.... is that correct?
Thanks in advance for taking the time to answer this question

The TL072 is a dual operational amplifier, meaning that the package contains two identical op-amps. Here is the data sheet::
http://www.ben.cz/_d/datasheet/tl072.pdf

 

The TL072 is a dual operational amplifier, meaning that the package contains two identical op-amps. Here is the data sheet::
http://www.ben.cz/_d/datasheet/tl072.pdf

Thanks alot, that was my guess but I wanted to make sure

 

For things like this you find the answers on the datasheet available on a Google search.

 

Welcome to AAC!

The electrical diagram that I found online Show 2 op amps drawn on the schematics.

You're going to find out fairly quickly that we prefer schematics to a bunch of words describing connectivity that will likely contain insufficient details for anyone to comprehend.

In parentheses beside the first op amp it states... (both op amps are one TLO72) . I know that sounds pretty self-explanatory, but to be sure... that does mean he's actually using a single op amp and only shown as two on the schematics in order to make it easier to understand where everything connects.... is that correct?

A proper schematic would show the IC designators and pin numbers. Since TL072 contains 2 opamps, one would likely be labeled 'A' and the other 'B', e.g. IC1A and IC1B.

 

If you are using only one opamp then why use a TL072 dual opamp? You must properly disable the unused opamp to prevent it from oscillating. Use a TL071 opamp instead and it costs less. It has the same 8 pins package and the datasheet shows which pin is which.

 

Please post the schematic you are using, or a link. I know this will come as a shock and undermine your faith in the universe, but some of the information on the innergoogle is incorrect.

ak

 

Google found the schematic at www.electroschematics.com .

 

Glad to see there is a differentiator in there, but what's with the giant attenuator followed by giant gain?

ak

 

Glad to see there is a differentiator in there, but what's with the giant attenuator followed by giant gain?

ak

The circuit is silly.