Nth-order OTA-C (Operational Transconductance Amplifiers and Capacitors) filter structures are realized by using the analytical synthesis method to achieve the following three important criteria simultaneously: filters use just n grounded capacitors, each of which is located at each of just n nodes in the realized circuit, because they use smaller area in the IC, and they can absorb equivalent shunt capacitive parasites; filters employ only single-ended-input OTAs to overcome the feed-through effects due to finite input parasitic capacitances associated with double-input OTAs to replace the same positions of the n given capacitors; and filters have the least number-of components (passive and active) for a given order to reduce power consumption, chip areas, and noise. Both the first and the second criteria lead to the minimum parasitic distortion and make the most precise output signals. And the third criterion produces the cheapest chip.