Lm741

bertus

Joined Apr 5, 2008
22,270
Hello,

In the datasheet is stated ±5 Volts supply.
This means taht 9 Volts is to low.
Also there is stated that the LM741 is an obsolete component.

Bertus
 

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beenthere

Joined Apr 20, 2004
15,819
In the datasheet is stated ±5 Volts supply.
Dropped a place. That is +/-15 volts in the data sheet.

What do you want to do? There are a huge number of better op amps, and many that are designed to operate with a single supply.
 

Audioguru

Joined Dec 20, 2007
11,248
The 741 opamp is 42 years old.

The written spec's are only with a plus and minus 15V supply but the "typical" graphs all show a supply as low as plus and minus 5V. With a supply as low as only plus and minus 5V then the typical output swing is shown to be almost nothing.
 

Thread Starter

h.z

Joined Nov 27, 2010
8
i asked just because I'm curious. 9V battery is easy to get, that's why I was wondering if the op amp could work with 9V supply voltage. as far as i know, op amp can amplify the input voltage to maximum the supply voltage. right?

so, audioguru op amp LM741 could work with 9V supply voltage?
 

thatoneguy

Joined Feb 19, 2009
6,359
You can use two 9V batteries to supply it, connect negative to positive, call that point "ground", for a dual supply.

That is sub-optimal, I'd suggest going with a more modern op amp.
 
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Wendy

Joined Mar 24, 2008
23,415
You could also use something like a LM324, which is 4 in one package. That chip is rated from 3V to 30V, which similar specs to a LM741. Both are available at Radio Shack.

The LM741 is extremely old, which translates into very poor specs compared to more modern types.

Creating a Virtual Power Supply Ground
 

Thread Starter

h.z

Joined Nov 27, 2010
8
You could also use something like a LM324, which is 4 in one package. That chip is rated from 3V to 30V, which similar specs to a LM741. Both are available at Radio Shack.
Minimum supply voltage is 3V? that is very low. so, you're saying i could use 9V supply voltage for LM741?
 

retched

Joined Dec 5, 2009
5,207
No, you cant use one 9v battery with a 741.

Take 2 9v batteries connect them in series.

Take the '+' on battery 'A' and connect it to the '-' on battery 'B'

The wire that connects the two batteries can now be your GROUND.

The '+' on battery 'B' is now +9v Hook that to the positive supply pin on the 741
The '-' on battery 'A' is now -9v Hook that to the negative supply pin on the 741

That will allow you to work with a LM741.

If you are just trying to learn theory, then thats fine, but If you are trying to make a project to keep and use, you can, and should, find better OPAmps.
 

Audioguru

Joined Dec 20, 2007
11,248
so, audioguru op amp LM741 could work with 9V supply voltage?
Simply read the datasheet.
The written spec's guarantee operation only when the supply is a total of 30V.
The graphs show very poor performance for "typical" devices at low voltages down to 10V.
Some do not work when the supply is 10V or less.

A 9V battery drops to only 6V as it is used.
An MC34071 or TLE2141 opamp works well with a supply down to only 3V and 4V. Both have guaranteed specs with a 5V supply. They have very low distortion and produce full output at 100kHz. Duals and quads are available.
 

R!f@@

Joined Apr 2, 2009
9,918
throw the 741 out of the window.

Get the most reason single ended supply opamp.
Will work with 9V and will last longer in a battery app.

I wonder why Indian uni's still get the students to use those obsolete components.

Oh wait, I forgot.. it's all they have around in thousands.
 

JoeJester

Joined Apr 26, 2005
4,390
So I guess the reasons they made us use it last year in a project in university where purely historical? :p
Nope. The reason the universities use the 741 is the same reasons you don't use them. They make great training aids.
 

Wendy

Joined Mar 24, 2008
23,415
Nope. The reason the universities use the 741 is the same reasons you don't use them. They make great training aids.
Agreed. All a standard op amps flaws happen much sooner with a 741.

I mentioned the LM324 as an alternate to the 741. I talked about what a LM324 could do with power supply voltages. It is almost as old as the 741 though, there are much better out there.

For all their flaws, which are legion, they are tough little chips, and a lot of them were made.
 
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