Abstract: According to the present invention, semiconductor device breakdown voltage can be increased by embedding field shaping regions within a drift region of the semiconductor device. A controllable current path extends between two device terminals on the top surface of a planar substrate, and the controllable current path includes the drift region. Each field shaping region includes two or more electrically conductive regions that are electrically insulated from each other, and which are capacitively coupled to each other to form a voltage divider dividing a potential between the first and second terminals. One or more of the electrically conductive regions are isolated from any external electrical contact. Such field shaping regions can provide enhanced electric field uniformity in current-carrying parts of the drift region, thereby increasing device breakdown voltage.

Abstract: An electronic system includes a circuit board, a first conducting element, a second conducting element and at least one connecting element. In this case, the circuit board has at least one through hole and at least one grounding unit disposed around the through hole. The first conducting element is disposed on one side of the circuit board, and the second conducting element is disposed on the other side of the circuit board. The connecting element is disposed through the through hole for connecting the first conducting element and the second conducting element.

Abstract: An electronic system includes a circuit board, a first conducting element, a second conducting element and at least one connecting element. In this case, the circuit board has at least one through hole and at least one grounding unit disposed around the through hole. The first conducting element is disposed on one side of the circuit board, and the second conducting element is disposed on the other side of the circuit board. The connecting element is disposed through the through hole for connecting the first conducting element and the second conducting element.

Abstract: In one embodiment, a filter with a main signal path having one or more biquadratic filter sections is tuned using a tuning circuit based on a biquadratic filter that can be configured to oscillate at the filter's cutoff frequency. In one application, a tuning circuit outside of the main signal path is used to tune each biquadratic filter section of the main signal path. In another application, each filter section along the main signal path has a biquadratic filter that can oscillate and corresponding tuning elements that enable the filter section to tune itself. According to certain embodiments of the present invention, a biquadratic filter is made to oscillate by applying a common-mode voltage signal to the inputs of the filter's third transconductor cell to make the cell's transconductance go to zero. The invention may also be implemented in the context of filters having ladder structures in their main signal path.

Abstract: An electronic device includes a first metal case, a second metal case, an electronic unit, a first heat insulation layer and a second heat insulation layer. In this case, the first metal case has a plurality of first holes, and the second metal case has a plurality of second holes. The first metal case is assembled with the second metal case to form an accommodating space. The electronic unit is disposed in the accommodating space. At least one surface of the first metal case is coated with the first heat insulation layer, and at least one surface of the second metal case is coated with the second heat insulation layer.

Abstract: An expandable heat sink is used for dissipating heat of a heat source on a main board. The heat sink comprises a main body and an expanded body. The main body comprises a main-body contact surface, which is contacted with the heat source, and a plurality of first fins. The first fins compose a main connecting portion. Furthermore, the expanded body comprises a plurality of second fins and the second fins compose an expanded connecting portion. The expanded connecting portion is removably connected to the main connecting portion.

Abstract: A capacitor cancellation method and apparatus for use in an interface circuit having a transformer blocking capacitor. The method includes sensing a voltage across the transformer blocking capacitor and generating a cancellation signal to compensate for the effect of the transformer blocking capacitor. The apparatus includes a sensor to sense a differential voltage across the transformer blocking capacitor to develop a capacitor signal and an amplifier to amplify the capacitor signal to obtain a cancellation signal.

Abstract: A spinal expanding apparatus includes multiple supports extendable out of passages in a body and a bolt movably received in the body. The bolt has multiple grooves in an outer periphery of the bolt to correspond to bottom conical heads of the supports. Therefore, advancement of the bolt is able to force the supports to simultaneously extend out of the passages of the body. Each of the supports has a travelling distance the same as the others so that two adjacent spines are evenly separated.

Abstract: An amplifier having an improved output current drive capability includes an input stage and an output stage. An input of the output stage is operatively coupled to an output of the input stage. The amplifier further includes a current regeneration circuit operatively coupled to the input of the output stage in a feedback arrangement, the current regeneration circuit feeding back a current to the output circuit in accordance with a predetermined scale factor, the fed back current being proportional to an input current supplied to the output stage. The input current supplied to the output stage is dynamically adjustable by the current regeneration circuit in response to an input current requirement at the output stage.

Abstract: A capacitor cancellation method and apparatus for use in an interface circuit having a transformer blocking capacitor. The method includes sensing a voltage across the transformer blocking capacitor and generating a cancellation signal to compensate for the effect of the transformer blocking capacitor. The apparatus includes a sensor to sense a differential voltage across the transformer blocking capacitor to develop a capacitor signal and an amplifier to amplify the capacitor signal to obtain a cancellation signal.

Abstract: An amplifier having an improved output current drive capability includes an input stage and an output stage. An input of the output stage is operatively coupled to an output of the input stage. The amplifier further includes a current regeneration circuit operatively coupled to the input of the output stage in a feedback arrangement, the current regeneration circuit feeding back a current to the output circuit in accordance with a predetermined scale factor, the fed back current being proportional to an input current supplied to the output stage. The input current supplied to the output stage is dynamically adjustable by the current regeneration circuit in response to an input current requirement at the output stage.

Abstract: A line circuit whose circuit components are selectively controllable by a microprocessor/DSP to provide normal BORSCHT functions or to be selectively tested without need for an electromechanical relay to isolate the line circuit from the loop conductors. The conventional line transformer is advantageously replaced by a loop current feed resistor network and either a high voltage or a lower voltage battery may be connected to provide loop current to the resistor network through a current regulator circuit and battery switch circuit. In normal operation, an ac feedback path, which includes the line receive amplifier, increases the terminating impedance above the dc value of the feed resistors so the loop termination resistor network may match the characteristic impedance of the loop at the audio frequencies employed.

Abstract: A line circuit provides BORSCHT functions and supplies the customer loop through a feed resistor network and current limiter either from a high voltage battery to provide for maximum signaling range or from a lower voltage battery to conserve power. The current limiter operates under the control of a microprocessor/DSP which selectively applies or denies power to isolate or include components for testing and controls the switching in and out of transistors to control the scaling factor between the channel width-to-length ratios of the current mirror's input and output FET transistors according to the type of test or operating condition dictated by the microprocessor while the input reference current to the current mirror is maintained constant.