Signal flow graph structure of high-pass filter useful for OTA-C

In this paper, a signal flow graph structure of high-pass filter useful for OTA-C is presented. The structure of the graph is similar to the ones of low-pass and band-pass filters. Realization of the graph in OTA-C is integrator-based and the proposed graph could be more easily implemented as an electronic circuit than other graphs. Unfortunately the design involves some floating capacitors instead of the grounded ones and not all of nodes have desired capacitances to ground. In the paper an example that compares characteristics of third order high-pass filters of different structures is presented