Abstract: A voltage supply circuit which suppresses generation of current spikes in the power source current in operation, reduce noise, simplify the circuit configuration, and decrease the cost. Clock signal CLK at a prescribed frequency is supplied to charge pump driver (10); current sources IS1, IS2, . . . IS6 work at timing set with clock signal CLK to output driving currents; and, corresponding to the driving currents, capacitors C1, C2 . . . are alternately charged or discharged; the charge stored in the capacitor of a preceding stage is sequentially sent to the later capacitor stage, and a boosted voltage higher than power source voltage Vcc is obtained at output terminal T2. In the charge pump type booster, since capacitors are driven with current sources, it is possible to reduce spike noise in the boosting operation, and influence on other analog circuits can be suppressed.

Abstract: The objective of the invention is to provide a booster circuit with reduced power consumption and switching noise. Booster circuit 1 of the present invention has gate circuits 41-47 an auxiliary control circuit 9. Each of gate circuits 41-47 has charging/discharging circuit 11 and auxiliary charging/discharging circuit 12 used for charging/discharging capacitors 51-57. Under the control of auxiliary control circuit 9, said charging/discharging circuit 11 can operate independently or operate together with auxiliary charging/discharging circuit 12. When the booster circuit is started, charging/discharging circuit 11 and auxiliary charging/discharging circuit 12 are operated together to increase the drivability of gate circuits 4. As a result, the charging time of capacitors 51-57 in charge-pump circuits 21-27 can be shortened. On the other hand, at steady state, charging/discharging circuit 11 operates independently.

Abstract: A voltage supply circuit which suppresses generation of current spikes in the power source current in operation, reduce noise, simplify the circuit configuration, and decrease the cost. Clock signal CLK at a prescribed frequency is supplied to charge pump driver (10); current sources IS1, IS2, . . . IS6 work at timing set with clock signal CLK to output driving currents; and, corresponding to the driving currents, capacitors C1, C2 . . . are alternately charged or discharged; the charge stored in the capacitor of a preceding stage is sequentially sent to the later capacitor stage, and a boosted voltage higher than power source voltage Vcc is obtained at output terminal T2. In the charge pump type booster, since capacitors are driven with current sources, it is possible to reduce spike noise in the boosting operation, and influence on other analog circuits can be suppressed.

Abstract: The objective of the invention is to provide a booster circuit with reduced power consumption and switching noise. Booster circuit 1 of the present invention has gate circuits 41-47 an auxiliary control circuit 9. Each of gate circuits 41-47 has charging/discharging circuit 11 and auxiliary charging/discharging circuit 12 used for charging/discharging capacitors 51-57. Under the control of auxiliary control circuit 9, said charging/discharging circuit 11 can operate independently or operate together with auxiliary charging/discharging circuit 12. When the booster circuit is started, charging/discharging circuit 11 and auxiliary charging/discharging circuit 12 are operated together to increase the drivability of gate circuits 4. As a result, the charging time of capacitors 51-57 in charge-pump circuits 21-27 can be shortened. On the other hand, at steady state, charging/discharging circuit 11 operates independently.

Abstract: The objective of the invention is to provide a booster circuit with reduced power consumption and switching noise. Booster circuit 1 of the present invention has gate circuits 41-47 an auxiliary control circuit 9. Each of gate circuits 41-47 has charging/discharging circuit 11 and auxiliary charging/discharging circuit 12 used for charging/discharging capacitors 51-57. Under the control of auxiliary control circuit 9, said charging/discharging circuit 11 can operate independently or operate together with auxiliary charging/discharging circuit 12. When the booster circuit is started, charging/discharging circuit 11 and auxiliary charging/discharging circuit 12 are operated together to increase the drivability of gate circuits 4. As a result, the charging time of capacitors 51-57 in charge-pump circuits 22-27 can be shortened. On the other hand, at steady state, charging/discharging circuit 11 operates independently.

Abstract: There is provided a UHF/VHF tuner in which complication in structure and increase in manufacturing costs are suppressed and broadcast receiving performance is improved by reducing variation in the reception sensitivity according to frequency when broadcast in the VHF band is received. In a UHF/VHF tuner for receiving both of a broadcast in the UHF band and a broadcast in the VHF band, one mixer and one UHF local oscillator are used for the broadcast in the UHF band, and one mixer, a VHF high-band local oscillator which is switched to be connected when the high band is selected and a VHF low-band local oscillator which is switched to be connected when the low band is selected are used for the broadcast in the VHF band.