602results about How to "Reduce circuit area" patented technology

A differential driving circuit used for low voltage differential signals and an electronic device incorporating the same are provided wherein no differential amplifiers are used or the number of differential amplifiers are reduced, thereby reducing the circuit area and the current consumption and further solving the problem of oscillation caused by noise, while a high driving performance is achieved. There are included a switch circuit an output circuit and a reference potential generating circuit. The switch circuit, which comprises MOS transistors, receives differential signals and outputs current signals. The output circuit comprises an NMOS transistor, an end of which is connected to the power supply potential of a higher potential side, the other end of which is connected to a node of the switch circuit and which acts as a source follower, and an PMOS transistor, an end of which is connected to the power supply potential of a lower potential side, the other end of which is connected to the other node of the switch circuit and which acts as a source follower. The reference potential generating circuit supplies reference potentials to the respective gates of the PMOS and NMOS transistors. The reference potential generating circuit includes a potential varying means that varies the differential potentials with an offset potential kept constant. Further, there is included an emphasis circuit for the output circuit.

A control circuit is employed for controlling a wireless power receiving apparatus that receives an electric power signal from a wireless power transmission apparatus. An electric power detection unit detects the received electric power PRX received by the wireless power receiving apparatus. A control unit generates a control signal CE for controlling the electric power PTX to be transmitted by the wireless power transmission apparatus. When the received electric power PRX detected by the electric power detection unit falls despite the control signal CE not indicating an instruction to lower the electric power PTX to be transmitted, an abnormal state judgment unit judges that an abnormal state has occurred.

A semiconductor integrated circuit with a PLL (Phase Locked Loop) built therein is used in a semiconductor integrated circuit for wireless communication. The PLL circuit generates an oscillation signal having a predetermined frequency, which is combined with a receive signal or a transmit signal for wireless communication. The PLL circuit includes a VCO capable of switching an oscillation frequency band, a variable divider, a loop filter and a phase comparator. An oscillation frequency of the VCO is controlled according to the difference in phase between a signal obtained by dividing the output of the VCO and a reference signal, and a discrimination circuit makes a decision as to a lead or delay of the phase of an output of the variable divider with respect to a reference signal having a predetermined frequency. An auto band selection circuit generates a signal for selecting a frequency band for the VCO.