Design of a DC Amplifier which has a gain of around 100......

I want to design a DC amplifier,which can convert an input DC voltage of the order of around 500 mV to around 9-10V.Can anyone please help me to find a good circuit for that?

Any operational amplifier circuit connected as a ''Non-inverting Amplifier'' will do the job.

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You may use for example LM358

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You can use the following differential amplifier
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I'm confused about the gain you want, in the title you say 100x and then you say that you want the 500mV input to become 10v which is a gain of 20x

Alex

alexan_e said:

You can use the following differential amplifier
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I'm confused about the gain you want, in the title you say 100x and then you say that you want the 500mV input to become 10v which is a gain of 20x

Alex

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Oh sorry alex...................i forgot to mention one thing .Actually I need two circuits,which can amplify signals from 0 to 500 mV to a max voltage of 10V and another ckt which can amplify 0 to 100mV to 10V.Thanks for helping to notice my mistake....

denniskthomas said:

Oh sorry alex...................i forgot to mention one thing .Actually I need two circuits,which can amplify signals from 0 to 500 mV to a max voltage of 10V and another ckt which can amplify 0 to 100mV to 10V.Thanks for helping to notice my mistake....

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Hi dennis,

you should know that it is more challenging to design resp. select a good dc amplifier rather than an ac amplifier.
In this context "good" means that the amplifier must output a signal that really depends "only" on the input signal and not (or in reality: only very little) on internal bias voltage uncertainties or variations.
Therefore, the simple answer: Select an opamp (or an differential resp. instrumentation amp) that has an offset voltage as low as necessary. I know "as necessary" is a rather weak term. But it really depends on your accuracy requirements.
The problem areas are - of course - very low signal voltages.
Example: 1mV input must lead to 100 mV output. Sounds simple: gain of 100 - however, what, if there is an offset that produces 20mV or 50mV at the output node without any input voltage?
Therefore, it is very important to know the actual range of your input signals and your accuracy requirements.