I recently came across a block diagram of a state variable filter on one of my reference books which looks like this:
I am not sure about the negative sign going into the summing point from the side of Vin. In my limited experience with control systems I have not encountered this and do not understand what it implies.
Without taking into consideration the negative sign of Vin, the transfer function I came up with is:
My question is not whether the transfer function is correct, but simply what effect does the negative sign next to Vin mean and how it affects the transfer function above. Thanks!