摘要:
A power MOSFET for a high frequency amplification element having good output power characteristics and high frequency characteristics is described. In the power MOSFET, a shield conductive film electrically connected to via an insulating film is arranged over a drain-offset semiconductor region. A wiring for a drain electrode is so arranged as to extent in parallel to the shield conductive film at one end side of the shield conductive film. On the other hand, a wiring for the gate electrode, a wiring for a source electrode and a gate shunt wiring are arranged in this order to extend in parallel to each other at the other end side of the shield conductive film. The shield conductive film is so formed that the thickness thereof is smaller than that of the wiring for the gate electrode. In this way, the input and output capacitances of the MOSFET can be decreased.
摘要:
In a high frequency amplifying MOSFET having a drain offset region, the size is reduced and the on-resistance is decreased by providing conductor plugs 13 (P1) for leading out electrodes on a source region 10, a drain region 9 and leach-through layers 3 (4), to which a first layer wirings 11a, 11d (M1) are connected and, further, backing second layer wirings 12a to 12d are connected on the conductor plugs 13 (P1) to the first layer wirings 11s, 11d (M1).
摘要:
A snow removing machine has a vehicle body having a body frame, a snow removing section mounted on a front portion of the body frame for removing snow, an operating handle mounted to a rear portion of the body frame and having a first handle portion and a second handle portion, and a pair of grip portions each mounted on a respective one of the first and second handle portions of the operating handle. A forward and aft drive changeover switch is directly mounted on the first handle portion of the operating handle for changing over a traveling direction of the vehicle body. A height control operation lever is directly mounted on the first handle portion of the operating handle for adjusting a height of the snow removing section. A speed control operation lever is directly mounted on the second handle portion of the operating handle for adjusting a traveling speed of the vehicle body.
摘要:
To enable easy replacement of a soiled fingerprint reading window. To reduce the number of light sources and achieve miniaturization. An aperture 5 is formed in part of a case K constituting the outer shell of a fingerprint recognition device, aperture 5 being covered by a cover member 4. Cover member 4 that covers aperture 5 constitutes part of case K. An aperture 6 formed in cover member 4 is covered by a window member 7 for fingerprint reading consisting of an optically transparent member. Window member 7 is arranged on the under-surface of cover member 4 and is resiliently held by the holding feet 11 formed on cover member 4. Light source 42, light-guide plate 43, reflection mirrors 33 and 34, image pick-up lens 35 and image pick-up element 36 are held by holding body H which is fixedly arranged in case K. Window member 7 is clamped between supporting faces 38 of holding body H and cover member 4 so as to be immovable. Light-guide plate 43 is arranged adjacent and inclined with respect to window member 7. Detection light rays from light-emitting elements 42 are sufficiently diffused while passing through light-guide plate 43 and are emitted in planar fashion from light-guide plate 43 towards window member 7.
摘要:
There is disclosed a semiconductor apparatus such as a power MOSFET, an IGBT, or the like having therein a control circuit such as an over-heating protection circuit and an over-current protection circuit, which realizes both of high-speed operation and prevention of erroneous operation caused by a parasitic device.In order to prevent erroneous operation of a power MOSFET 30 and a protection circuit 21 caused by a parasitic npn transistor 29 of an MOSFET 32, a control circuit 20 controls so that when the voltage of a gate terminal 2 is positive relative to that of a source terminal 3, a switch circuit SW3 is turned on, when the voltage of the gate terminal 2 is negative relative to that of the source terminal 3, a switch circuit SW2 is turned on, and when the gate terminal 2 and the source terminal 3 have an almost same potential and a drain terminal 1 has a high potential, the switch circuit SW2 is turned on.By adding such a control circuit, an insulated gate semiconductor apparatus having therein the protection circuit according to the invention can reduce a leakage current flowing from the drain terminal to the gate terminal when a negative voltage is applied to the gate and can operate at high speed without causing drop of a drain breakdown voltage.
摘要:
In a semiconductor circuit device having a substrate, a first region of a first conductivity type formed in the substrate, a second region of a second conductivity type contacted to the first region and a MISFET formed in the second region, there is a problem of that a parasitic npn bipolar transistor constituted by the first region, the second region and a source or drain of the MISFET activates. In this invention, switching circuitry is provided to make the second region floating or to connect the second region with the source or drain of the MISFET when a negative first input voltage is input to a source or a drain of the first MISFET. By virtue of the switching circuitry, no base current of the parasitic bipolar transistor occurs, thereby preventing operation of the parasitic transistor. In particular, when the switching circuitry operates to cause the second region to float, the base of the parasitic bipolar transistor will float, and the bipolar transistor cannot operate. Alternatively, when the switching circuitry connects the second region with the source or drain, the base-emitter junction of the parasitic bipolar transistor will be shorted, which also prevents its operation.
摘要:
An improvement in conditions that protective functions of an insulated gate semiconductor device with a protection circuit incorporated therein are performed, an improvement in the cutoff of heating, the prevention of malfunctions and an improvement in ease of usage can be achieved.The insulated gate semiconductor device of the present invention comprises a power insulated gate semiconductor element (M9), at least one MOSFET (M1 through M7) for a protection circuit, for controlling the power insulated gate semiconductor element, a constant-voltage circuit using forward voltages developed across diodes (D2a through D2f) for the constant-voltage circuit, and voltage restricting diodes (D1 and D0a through D0d) for controlling the upper limit of a power supply voltage of the constant-voltage circuit. Power to be supplied to the voltage restricting diodes is supplied from an external gate terminal of the power insulated gate semiconductor element.The present invention can bring about an advantageous effect that an improvement in reliability of the insulated gate semiconductor device and an improvement in the ease of use can be achieved.
摘要:
A method of fabricating semiconductor devices which include vertical elements and control elements. A well is formed by etching in a semiconductor substrate of a first conductivity type, and a first epitaxial layer having a second conductivity type opposite to the first conductivity type is epitaxially grown, followed by etching and/or grinding and/or polishing to fill said well. Further, a second epitaxial layer of the first conductivity type is epitaxially grown on the substrate and on the first epitaxial layer, and an impurity-doped layer of the second conductivity type for isolation is formed in the second epitaxial layer to penetrate therethrough. A first element is formed in the second epitaxial layer in a portion that corresponds to the well, and a second element having a vertical structure and having a current capability higher than that of the first element is formed except a portion of the second epitaxial layer that corresponds to the well.
摘要:
A speed control apparatus for a DC motor operable with a low voltage battery has a reference voltage generating circuit capable of operable with a low voltage such as 1 V and is settable for output voltage and for temperature coefficient independently each other and has a differential amplifier which is operable with a very small input voltage and capable of operable with such a low voltage.