Abstract: A semiconductor device includes: a plurality of external signal input means; an external input unit having a switch each connected between the external signal input means and a read line and electrically connected for output from the external signal input means on the read line; a shift register receiving an external control signal and an external clock signal and synchronized with the external clock signal to shift successively the external control signal to provide shifted data and output the external control signal to electrically connect the switches in accordance with the shifted data; an output circuit receiving the external control signal from the shift register and externally outputting the external control signal; and a frequency divider circuit dividing the external clock signal in frequency to generate and output an internal clock signal, wherein the output circuit is synchronized with the internal clock signal to externally output the external control signal.

Abstract: An image reading device ready to operate at higher speed is built as an IC chip having a plurality of processing sections, of which each has a plurality of image reading photoelectric conversion elements, a plurality of transistors for reading a photoelectric conversion signal from the image reading photoelectric conversion elements, a signal selection circuit for sequentially selecting the plurality of transistors, and a signal output line by way of which the photoelectric conversion signal is transmitted.

Abstract: A semiconductor device includes a photoelectric conversion element outputting an electric signal in accordance with an externally input optical signal, an internal circuit processing the electric signal, a signal terminal inputting or outputting a signal to the internal circuit, a first voltage terminal supplying a first voltage to the internal circuit, and a second voltage terminal supplying a second voltage lower than the first voltage to the internal circuit. The semiconductor device further includes a first protection element connected in an electrically reverse direction between the signal terminal and the first voltage and having at least one PN junction and a second protection element connected in an electrically reverse direction between the first voltage and the second voltage and having at least one PN junction, so that immunity to electrostatic noise can be improved and electrostatic breakdown and malfunction of the photoelectric conversion element can be suppressed.

Abstract: A semiconductor device includes: a plurality of external signal input means; an external input unit having a switch each connected between the external signal input means and a read line and electrically connected for output from the external signal input means on the read line; a shift register receiving an external control signal and an external clock signal and synchronized with the external clock signal to shift successively the external control signal to provide shifted data and output the external control signal to electrically connect the switches in accordance with the shifted data; an output circuit receiving the external control signal from the shift register and externally outputting the external control signal; and a frequency divider circuit dividing the external clock signal in frequency to generate and output an internal clock signal, wherein the output circuit is synchronized with the internal clock signal to externally output the external control signal.

Abstract: In an image reading device having a plurality of photoelectric conversion elements formed in one or more rows on an IC chip and a conductor layer having openings formed therein for limiting light striking the photoelectric conversion elements, a conductor having substantially the same width as the conductor layer is formed in the area extending from the photoelectric conversion element located at each end of the IC chip to the chip edge. This arrangement helps make light shield conditions nearly equal for the photoelectric conversion element located at an end of the IC chip and for the other photoelectric conversion elements.

Abstract: An image reading device ready to operate at higher speed is built as an IC chip having a plurality of processing sections, of which each has a plurality of image reading photoelectric conversion elements, a plurality of transistors for reading a photoelectric conversion signal from the image reading photoelectric conversion elements, a signal selection circuit for sequentially selecting the plurality of transistors, and a signal output line by way of which the photoelectric conversion signal is transmitted.

Abstract: An image-sensing semiconductor device has, in addition to a plurality of photodiodes, a dummy photodiode. The dummy photodiode is fed with a bias repeatedly with a predetermined period, and the plurality of photodiodes are fed with a bias sequentially with a predetermined cycle. The differences between the individual output signals of the plurality of photodiodes and the output signal of the dummy photodiode are calculated sequentially by a differential amplifier.

Abstract: In an image reading device having a plurality of photoelectric conversion elements formed in one or more rows on an IC chip and a conductor layer having openings formed therein for limiting light striking the photoelectric conversion elements, a conductor having substantially the same width as the conductor layer is formed in the area extending from the photoelectric conversion element located at each end of the IC chip to the chip edge. This arrangement helps make light shield conditions nearly equal for the photoelectric conversion element located at an end of the IC chip and for the other photoelectric conversion elements.

Abstract: An optical communication device includes an IrDA modulation circuit and an ASK modulation circuit, one of which modulates transmission data. Modulated data is applied to a driver which drives a light emission diode (LED) in accordance with the modulated data. On the other hand, reception data received by a photo-diode is amplified by an amplifier, and reception data outputted from the amplifier is demodulated by an IrDA demodulation circuit or an ASK demodulation circuit. The IrDA modulation circuit, the ASK modulation circuit, the IrDA demodulation circuit and the ASK demodulation circuit are formed by an MOS process, and the driver and the amplifier are formed by a bipolar process. The MOS process and the bipolar process are executed on the same substrate, whereby such circuits are incorporated into a single IC. The IC, the LED and the photo-diode are molded by a resin.