op amp bias

[adam c]

I try to build an adder using a quad op amp, lm348.

Is the above circuit correct? I heard that op amp need to be bias. What is mean by bias? And how to bias an op amp?

I have only little knowledge on electronic.

 

[crutschow]

In this case I believe the bias is just referring to the plus and minus 15V power.

The pot connection on the last stage is not shown correctly. The wiper of the potentiometer should be shown as going to the inverting input of the op amp.

 

[elnino86]

I try to build an adder using a quad op amp, lm348.

Is the above circuit correct? I heard that op amp need to be bias. What is mean by bias? And how to bias an op amp?

I have only little knowledge on electronic.

From my understanding, bias is a DC value.As we applied AC signal,the output is about to vary within the bias point.The purpose of biasing is to keep the op amp from saturating.

It depend on the your application.Can you attached your image in JPG file?It more convinience for other people to look at it.

Here is my past thread, im asking one of the senior member here.He explain a little bit about biasing on my thread.
https://www.electro-tech-online.com/threads/ecm-pre-amplifier.87531/

 

[audioguru]

The bias voltage of your circuit is the 0V at the non-inverting input of the first opamp.
If the circuit uses a single supply voltage then the bias voltage should be at half the supply voltage.

 

[Roff]

In this case I believe the bias is just referring to the plus and minus 15V power.

The pot connection on the last stage is not shown correctly. The wiper of the potentiometer should be shown as going to the inverting input of the op amp.

It appears to me to be connected as you recommended.