Biasing of OPAMP - a fix without needing to generate the -3v

[awan]

Biasing of OPAMP

Hi;

I have a question in biasing an OPAMP. I only have +3volts supply on my circuit.

The OPAMP i am using requires +3volts and -3volts. So, do i need to generate -3volts supply for biasing? If i use 0volts instead of -3volts then my simulation is incorrect.

What is the bestway to fix this problem. Is there a fix without needing to generate the -3volts?

Thanks

 

[Audioguru]

Biasing of OPAMP

A few opamps work when the supply is only 3V.
Use one and bias its input at half the supply voltage (+1.5V) and capacitive-couple the signals to its input and output..

 

[messghati]

Biasing of OPAMP

please hello to all.
I want to ask about how to saturate all transistor in op amp and have a 75 db in DC gain

 

[Audioguru]

Re: Biasing of OPAMP

please hello to all.
I want to ask about how to saturate all transistor in op amp and have a 75 db in DC gain

You cannot saturate all transistors in an opamp because some are in differential and push-pull pairs.

An amplifier will not amplify if one or more of its amplifying transistors is saturated.

An opamp typically has an open-loop DC gain of 120dB so a closed-loop gain of only 75dB is easy. It will have 45dB of negative feedback.

 

[Ronnie]

Re: Biasing of OPAMP

you need to give more details of your application, why do you need -3v?
what op amp are you using etc...

 

[abhisheksbox]

Biasing of OPAMP

please dont see the peak values of bais, just find out the potential difference required for op-amp operation. for more clear answer plz provide more details abt the circuit.