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Non inverting amplifier using OPAmp LM358

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ark5230

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I constructed non inverting DC amplifier using 1/2 LM 358 with a gain of 10 employing the standard circuit.
It does work at single supply of 5 V.
Every thing is fine if the output levels are less than 3 V approximately.
The output never exceeds certain value that ranges from 2.6 to 3 V irrespective of gain and input.
Some sort of saturation like effect !!
As I know very little or latest advancements, I think this is the characteristic of OPAmp LM358 which I could not locate from the data sheet or there is something that is missing in my implementation.
 

Hi,

You are right, it is a characteristic of the op amp. The datasheet says that for 30V supply V out high is 26V, so you can guess that the output limit is a couple of volts below V supply. I have to admit the datasheet wasn't so clear, and if it said so in the introduction would be helpful. It looks like the LM324 - can reach ground but can't reach V+/V-.
 
Great @d123
Thanks a lot for such a quick response that clarified something the data sheet cound not.
 

You may use "Rail-to Rail" OpAmp instead of LM358
 

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@BigBoss
Thanks for the reply, any further hint or link please, single supply is desirable.

@ Audioguru
So true
I missed that as settled at solution (at the cost of lot of confusion and problems)
Thanks again.
 

Yes, just search "on rail-to-rail op amp" and/or "single supply op amp" and you should find many possibilities. In general, many of the older technology op amps work well within their limits, but as you discover they often have a couple of PN junction voltage drops less than the power supply rails for max output. Also you can find that the max +V output limit range is not the same as the greatest -V voltage range (assymetrical max limits).
 
ftsolutions said:
Yes, just search "on rail-to-rail op amp" and/or "single supply op amp" and you should find many possibilities. .........
Click to expand...
The LM358 is specified as a "single supply op amp" but it is not a "rail-to-rail" type.
That means the input and output can go to the negative rail, but not (necessarily) to the positive rail.
 
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