[sdiy] 5v ADV Bass / AD EG Question.

[harrybissell]

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Scott Gravenhorst wrote:

> Yes, the OTA is powered by +5v and 0 volts.  Biasing of the OTA is then
> identical to any dual supply set up.  This means that you need only the one
> +V/2 reference.  OTA circuits that I've seen all have a large resistor (like
> 100K) from signal input to OTA input, then there's a small resistor (like 1K)
> from OTA input to virtual ground.  This automatically biases the OTA input.
> If one OTA input is unused, it should be sent to virtual ground through a
> resistor of a size equal to the small resistor on the other input.

The idea of the equal value resistors is for bias current equalization, to keep
offset at a minimum.  In this type of application its probably not needed.

I'd probably just generate a negative supply for myself, unless absolute low
power
consumption was the most important thing.

H^) harry