NE5532 Opamp

[dark]

Hello;

The above opamp is rated for dual supply . Can we operate it on single supply (+12V)for audio preamp .

Regards

 

[Winterstone]

Each dual supply opamp can be operated with a single supply if designed for a proper bias point (normally at 50% of the supply). This requires specific bias resistors at the input (analog to BJT biasing).

 

[dougy83]

Each dual supply opamp can be operated with a single supply if designed for a proper bias point (normally at 50% of the supply). This requires specific bias resistors at the input (analog to BJT biasing).

Hey Winterstone, what do you mean by specific bias resistors? Is it more complicated than just matching the impedance each input sees?

 

[Winterstone]

Hey Winterstone, what do you mean by specific bias resistors? Is it more complicated than just matching the impedance each input sees?

Matching of which impedances?
The internet is full of opamp circuits for single supply operations. Spend some minutes for searching.

 

[dougy83]

Matching of which impedances? The internet is full of opamp circuits for single supply operations. Spend some minutes for searching.

You stated that "specific bias resistors" are required for "analog to BJT biasing". I was wondering what's so specific about them.

By "matching of impedances" I meant having equal external impedances to each input.

 

[dark]

You stated that "specific bias resistors" are required for "analog to BJT biasing". I was wondering what's so specific about them.

By "matching of impedances" I meant having equal external impedances to each input.

I guess he means to generate virtual ground with precision resistors . With Ne5532 I am not getting more than 1V amplification of ac signal . Can someone suggest me a superior amplifier then LM358 in terms of noise characteristics and details in datasheet . I need an output swing of about 6V max ac signal . Rgds

 

[alec_t]

I need an output swing of about 6V max ac signal

6V RMS = ~16.8V pk-to-pk, so you will need a supply voltage ~20V at least to prevent clipping.

 

[dark]

6V RMS = ~16.8V pk-to-pk, so you will need a supply voltage ~20V at least to prevent clipping.

6Vmax , It would be ok with 4V and rest of the gain can be increased by power amp.

 

[Winterstone]

You stated that "specific bias resistors" are required for "analog to BJT biasing". I was wondering what's so specific about them.

By "matching of impedances" I meant having equal external impedances to each input.

Yes - you are right. The resistors are not "specific". It was the wrong expression.
A resistive bias network is necessary for biasing the input and the output to approx. half of the single supply.
However, in most cases, equality of the input resistors (input dc current compensation) is not necessary.

 

[ronv]

Can someone suggest me a superior amplifier then LM358 in terms of noise characteristics and details in datasheet . I need an output swing of about 6V max ac signal . Rgds

Take a look at this one.

https://www.electro-tech-online.com/custompdfs/2013/02/sbos058.pdf

 

[dougy83]

Yes - you are right. The resistors are not "specific". It was the wrong expression.
A resistive bias network is necessary for biasing the input and the output to approx. half of the single supply.
However, in most cases, equality of the input resistors (input dc current compensation) is not necessary.

Thanks for clearing that up. I just thought you might have some pearls of wisdom contrary to what I thought I knew. Yes, offset error is generally not an issue for low gain and/or AC-coupled amplifiers.

 

[Winterstone]

.........I just thought you might have some pearls of wisdom ............

Surely I have ... nice expression. However, I don`t know where these pearls are, they are hidden (or gone ?).