Sanyo Electric Co., Ltd.

Semiconductor Components Industries, LLC

Sanyo Semiconductor Co., Ltd.

Katsu Horikoshi

Hisayoshi Uchiyama

Takashi Noma

Hiroshi Yamada

Hiroyuki Shinogi

Shinzo Ishibe

Yoshinori Seki

Masami Kato

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.

Semiconductor device

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. With this arrangement, synchronization is established between a received spread spectrum code and generated spread spectrum code, and then a communication carrier period starts. This makes it possible to ensure establishment of synchronization and data demodulation despite a longer time necessary for a receiver/transmitter employing a spread spectrum method to establish synchronization for spread spectrum codes.

Bi-directional transmitter/receiver system and bi-directional transmitter/receiver

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.

Automatic loudness control circuit

Growing community of inventors

Gunma, Japan

Katsu Horikoshi