CA3080 biasing


Joined Dec 26, 2010
I wondered about that when I saw it first, but I'm fairly sure the reason is to get the voltage required to control the CA3080 within the range available from the 3403 op-amp driving it.

The amplifier bias control input is only one junction potential above its negative supply input, and the 3403 does not seem able to go down that far.

Edit: Kubeek is right: I had to refer to this to see your circuit