Modern CMOS radio frequency (RF) Receivers have enabled efficient and increasing applications. The main requirement is to have system in a single chip, in order to minimize area and cost. For the purpose it is required the development of inductorless circuits for the key blocks of an RF receiver. Examples of this key blocks are RC oscillators, RF band pass filters, and Low Noise Amplifiers. The present dissertation presents an inductorless wideband MOSFET-only RF Non-Gyrator Type of Active Inductors with low area, low cost, and very low power, capable of covering the whole WMTS, and ISM, band and intended for biomedical applications.
The proposed circuit is based on a floating capacitor connected between two controlled current sources. The first current source, which is controlled by the circuit input voltage, has two objectives: supply current to the capacitor (2) and develop a voltage with 90º degrees in regard to the first current. The capacitor controls the second current source. The addition of one transistor compensates the capacitive parcel of the input current, in order to become purely inductive.
This model, based on Active Inductors (AI) takes advantage of the 130 MOS technology to optimize the control of the quality factor. In this sense, the proposed AIs can behave as a parallel RLC Oscillator, and examples of realizations for 662 MHz to 4.1 GHz range are given. A 1.2 V power source, supply the circuit with 56.4 W at the maximum oscillation frequency. With this results, it is possible to confirm the proposed objectives, in order to have a functional Active Inductor as a key block in RF transceivers
