Abstract:
An amplifier unit is provided, with which the need for manufacturing a photoelectric conversion IC in Bi-CMOS process is eliminated, and relatively low process cost of the photoelectric conversion IC is achieved. The input section of a buffer (the base of a transistor Q5) is connected with a plurality of patterns of phase compensation circuits each including a resistor and a capacitor connected in series. A bipolar transistor (Q6) is interposed between a positive power supply line and a capacitor (C2) forming a capacitance of the phase compensation circuit. By switching on/off the bipolar transistor (Q6), the capacitance value and resistance value of the phase compensation circuit are switched. Since the bipolar transistor (Q6) is interposed between the capacitor (C2) and the positive power supply line, base current (Isw) acting as a switch signal does not affect the amplifier unit.
Abstract:
A test circuit for testing not only characteristics of a current-voltage conversion circuit in which a light-receiving element is used but also characteristics of the light-receiving element includes: a current-mirror circuit 110 including a bipolar transistor Q1 and a bipolar transistor Q2 which are electrically connected to a light-receiving element PD1; a dummy light-receiving element PD_D which is an element identical to the light-receiving element PD1 and is equivalent in characteristics to the light-receiving element PD1; and a test terminal TP which is electrically connected to the bipolar transistor Q1 and the dummy light-receiving element PD_D.
Abstract:
The test circuit according to the present invention includes: a plurality of light-receiving elements; a plurality of amplifiers, each of which converts, into a voltage, a photoelectric current supplied from one of the light-receiving elements; and an electric current supplying unit which supplies an electric current to each of the light-receiving elements and each of the amplifiers. In this test circuit, the electric current supplying unit selectively supplies an electric current to a first group of light-receiving elements and to a second group of light-receiving elements, the first group of light-receiving elements including light-receiving elements, out of the plurality of light-receiving elements, which are neither vertically nor horizontally adjacent to each other, and the second group of light-receiving elements including light-receiving elements, out of the plurality of light-receiving elements, which are vertically or horizontally adjacent to the light-receiving elements of the first group of light-receiving elements.
Abstract:
A method for producing a semiconductor light emitting device includes the steps of forming a mask layer having a plurality of openings on a surface of a silicon substrate; and forming a column-like multi-layer structure including a light emitting layer in each of the plurality of openings with nitride semiconductor materials. A width between two adjacent openings of the plurality of openings of the mask layer is 10 &mgr;m or less.
Abstract:
An amplifier unit is provided, with which the need for manufacturing a photoelectric conversion IC in Bi-CMOS process is eliminated, and relatively low process cost of the photoelectric conversion IC is achieved. The input section of a buffer (the base of a transistor Q5) is connected with a plurality of patterns of phase compensation circuits each including a resistor and a capacitor connected in series. A bipolar transistor (Q6) is interposed between a positive power supply line and a capacitor (C2) forming a capacitance of the phase compensation circuit. By switching on/off the bipolar transistor (Q6), the capacitance value and resistance value of the phase compensation circuit are switched. Since the bipolar transistor (Q6) is interposed between the capacitor (C2) and the positive power supply line, base current (Isw) acting as a switch signal does not affect the amplifier unit.
Abstract:
The test circuit according to the present invention includes: a plurality of light-receiving elements; a plurality of amplifiers, each of which converts, into a voltage, a photoelectric current supplied from one of the light-receiving elements; and an electric current supplying unit which supplies an electric current to each of the light-receiving elements and each of the amplifiers. In this test circuit, the electric current supplying unit selectively supplies an electric current to a first group of light-receiving elements and to a second group of light-receiving elements, the first group of light-receiving elements including light-receiving elements, out of the plurality of light-receiving elements, which are neither vertically nor horizontally adjacent to each other, and the second group of light-receiving elements including light-receiving elements, out of is the plurality of light-receiving elements, which are vertically or horizontally adjacent to the light-receiving elements of the first group of light-receiving elements.