Abstract: The invention provides a semiconductor device which has a capacitor element therein to achieve size reduction of the device, the capacitor element having larger capacitance than conventional. A semiconductor integrated circuit and pad electrodes are formed on the front surface of a semiconductor substrate. A second insulation film is formed on the side and back surfaces of the semiconductor substrate, and a capacitor electrode is formed between the back surface of the semiconductor substrate and the second insulation film, contacting the back surface of the semiconductor substrate. The second insulation film is covered by wiring layers electrically connected to the pad electrodes, and the wiring layers and the capacitor electrode overlap with the second insulation film being interposed therebetween. Thus, the capacitor electrode, the second insulation film and the wiring layers form capacitors.

Abstract: The invention provides a semiconductor device which has a capacitor element therein to achieve size reduction of the device, the capacitor element having larger capacitance than conventional. A semiconductor integrated circuit and pad electrodes are formed on the front surface of a semiconductor substrate. A second insulation film is formed on the side and back surfaces of the semiconductor substrate, and a capacitor electrode is formed between the back surface of the semiconductor substrate and the second insulation film, contacting the back surface of the semiconductor substrate. The second insulation film is covered by wiring layers electrically connected to the pad electrodes, and the wiring layers and the capacitor electrode overlap with the second insulation film being interposed therebetween. Thus, the capacitor electrode, the second insulation film and the wiring layers form capacitors.

Abstract: A wireless type data transmission device (data carrier) has a receiver for receiving electric wave transmitted from a reader-writer, a rectifier for rectifying the received electric wave to generate a first voltage, and a booster for boosting the first voltage to produce a second voltage, which is higher than the first voltage, to drive an internal circuit of the wireless type data transmission device.

Abstract: To ensure establishment of synchronization and data demodulation among a number of transmitter/receivers using a spread spectrum method. Specifically, in a normal communication state, a second transmitter/receiver sends transmission data including a pilot carrier and a communication carrier. Receiving the transmission data, a first transmitter/receiver establishes synchronization between a spread code contained in the received spread spectrum signal and its own generated spread code, based on dummy data received during a pilot carrier period, and maintains the established synchronization. Thereafter, the first transmitter/receiver digitally demodulates data in the communication carrier. The resultant data is subjected to decoding and analog conversion to be converted into an audio signal. A control data is derived from the digitally demodulated data, and used to control the operation of the first transmitter/receiver.

Abstract: The PLL device includes means (6) for generating a, plurality of reference signals (FR1, FR2, FR3, FR4) having mutually differing phases, a variable frequency divider (11, 12, 13, 14) for dividing, in synchronization with the phases of a plurality of the reference signals, a frequency of an output signal (FO) of a voltage-controlled oscillator (15) that produces a signal having a frequency responsive to a control voltage (CV) supplied to generate a plurality of feedback signals (FV1, FV2, FV3, FV4) having mutually differing phases, phase comparators (7, 17, 8, 18, 9, 19, 10, 20) for comparing phases between the reference signals and the feedback signals corresponding to the reference signals respectively to produce a plurality of error signals (ER1, ER2, ER3, ER4), a low-pass filter (21) for filtering the error signals output from the phase comparators to produce the control voltage, and a control means (16, 26, 27) for controlling the number of the phase comparators that output the error signals to the low-p

Abstract: An automatic loudness control circuit for automatically controlling the magnitude of boosting of the low-frequency component of an audio signal in accordance with the output signal level of a power amplifier for driving a loud-speaker. The low-frequency component of the output signal from an audio signal source is boosted by a low frequency boosting circuit to prepare a low-frequency boost signal, which is then added to the output signal of the source, and the resulting signal is fed to the power amplifier. The magnitude of boosting by the boosting circuit is controlled according to the output level of the power amplifier and is therefore increased as the output level lowers. Consequently, the circuit assures optimum loudness control at all times, permitting the loudspeaker to produce dynamic sounds.