Abstract: The present invention relate to a wideband frequency generating apparatus using a frequency dividing method of dividing a frequency signal of a voltage control oscillator to expand a frequency generating range.

Abstract: The present invention relates to a derivative superposition circuit for linearization. The derivative superposition circuit for linearization includes a first active element that is provided with first to third terminals and in which the magnitude and direction of current flowing the second terminal to the third terminal changes on the basis of the magnitude of a voltage applied between the first and second terminals; and a second active element that is provided with first to third terminals and has complementary characteristics with the first active element. The first terminals of the first and second active elements are connected to each other so that a predetermined operational bias voltage is maintained by first and second power supplies through a first impedance, and are connected to an input end through a second impedance.

Abstract: A linear channel select filter for an Intermediate Frequency selector of a satellite broadcasting tuner, linearly changes a desired frequency by adjusting an output current, and includes: a transconductance (GM) current cell controller for determining a control voltage according to a select signal, generating the output current according to an differential input voltage, linearly controlling the output current according to the control voltage, and providing a linearly variable resistance according to the linearly controlled output current, and a capacitor circuit coupled to the GM cell controller to provide a capacitance to generate a cutoff frequency voltage according to the output current and the variable resistance. An occupying area and a size of the filter are reduced.

Abstract: A linear channel select filter having a simple structure is used for an IF selector of a satellite broadcasting tuner, linearly changes a desired frequency by adjusting an output current, and includes a GM current cell unit determining a control voltage according to a select signal, generating an output current according to an differential input voltage, linearly controlling the output current according to the control voltage, and providing a linearly variable resistance according to the linearly controlled output current, and a capacitor circuit coupled to the GM cell unit to provide a capacitance to generate a cutoff frequency voltage according to the output current and the variable resistance. An occupying area and a size of the filter is reduced.

Abstract: The present invention relate to a wideband frequency generating apparatus using a frequency dividing method of dividing a frequency signal of a voltage control oscillator to expand a frequency generating range.