Abstract: The electrical characteristics of a semiconductor device are enhanced. In the package of the semiconductor device, there are encapsulated first and second semiconductor chips with a power MOS-FET formed therein and a third semiconductor chip with a control circuit for controlling their operation formed therein. The bonding pads for source electrode of the first semiconductor chip on the high side are electrically connected to a die pad through a metal plate. The bonding pad for source electrode of the second semiconductor chip on the low side is electrically connected to lead wiring through a metal plate. The metal plate includes a first portion in contact with the bonding pad of the second semiconductor chip, a second portion extended from a short side of the first portion to the lead wiring, and a third portion extended from a long side of the first portion to the lead wiring.

Abstract: A semiconductor device capable of reducing an inductance is provided. In the semiconductor device in which a rectification MOSFET, a commutation MOSFET, and a driving IC that drives these MOSFETs are mounted on one package, the rectification MOSFET, a metal plate, and the commutation MOSFET are laminated. A current of a main circuit flows from a back surface of the package to a front surface thereof. The metal plate is connected to an output terminal via a wiring in the package. Wire bondings are used for wirings for connecting the driving IC, the rectification MOSFET, and the commutation MOSFET, all terminals being placed on the same plane. For this reason, the inductance becomes small and also a power source loss and a spike voltage are reduced.

Abstract: A switching regulator can convert an input voltage to a desired output voltage by ON-OFF controlling switching elements with PWM signals. The switching regulator can include a communication interface circuit that receives external operation instructions, an output voltage setting section that changes an output voltage to an output voltage setting value upon receiving an output voltage changing instruction from the outside, a voltage divider and an ADC that converts an error voltage into a digital error signal e[n], the error voltage being a difference between a reference voltage Vref and a detected output voltage value Vfb. The switching regulator can also include a controller that includes an operation control section for calculating a duty factor signal d[n] to determine an ON time proportion of the switching elements and an output voltage changing control section for controlling operation to change the output voltage.

Abstract: A digital control switching power supply unit converts an input voltage into a desired output voltage using a digitally controlled pulse width modulation (PWM) signal according to a switching cycle. The power supply unit includes an analog-to-digital converter (ADC). The ADC converts a result of a comparison between an output voltage and a reference voltage to a digital signal during a conversion cycle. The ADC includes a circuit for outputting a phase difference between a switching cycle and the conversion cycle, and a delay circuit. The delay circuit generates a delay output current based on a result of the comparison and the phase difference and determines the conversion time delay according to the delay output current. The delay circuit also generates a delay reference current based on the reference voltage and the phase difference and determining the duration of the conversion cycle according to the delay reference current.

Abstract: A semiconductor device capable of reducing an inductance is provided. In the semiconductor device in which a rectification MOSFET, a commutation MOSFET, and a driving IC that drives these MOSFETs are mounted on one package, the rectification MOSFET, a metal plate, and the commutation MOSFET are laminated. A current of a main circuit flows from a back surface of the package to a front surface thereof. The metal plate is connected to an output terminal via a wiring in the package. Wire bondings are used for wirings for connecting the driving IC, the rectification MOSFET, and the commutation MOSFET, all terminals being placed on the same plane. For this reason, the inductance becomes small and also a power source loss and a spike voltage are reduced.

Abstract: A fully integrated DC-DC converter utilizes digitally controlled dual output stages to achieve fast load transient recovery is presented. The DC-DC converter includes a main converter output stage connected in parallel with an auxiliary output stage. The main output stage is responsible for steady-state operation and is designed to achieve high conversion efficiency using large inductor and power transistors with low on-resistance. The auxiliary stage is responsible for transient suppression and is only active when a load transient occurs. The auxiliary output stage performs well with inductor and power transistors much smaller than those of the main switching stage and thus achieves well balanced power conversion efficiency and dynamic performance with a much smaller area penalty than previously described dual-output-stage converters.

Abstract: A semiconductor device capable of reducing an inductance is provided. In the semiconductor device in which a rectification MOSFET, a commutation MOSFET, and a driving IC that drives these MOSFETs are mounted on one package, the rectification MOSFET, a metal plate, and the commutation MOSFET are laminated. A current of a main circuit flows from a back surface of the package to a front surface thereof. The metal plate is connected to an output terminal via a wiring in the package. Wire bondings are used for wirings for connecting the driving IC, the rectification MOSFET, and the commutation MOSFET, all terminals being placed on the same plane. For this reason, the inductance becomes small and also a power source loss and a spike voltage are reduced.

Abstract: A switching power supply system controlling switching operations of switching devices by a control circuit to convert an input voltage into a desired output voltage, the system being provided with a under voltage lock out circuit including: an input voltage detection unit detecting an input voltage and producing an input voltage digital signal corresponding to the input voltage Vin; and a voltage level comparison unit carrying out digital comparison of the input voltage digital signal with each of two voltage detection level data and outputting the results of the comparisons as an output signal, in which by changing voltage detection level data stored in two registers, desired voltage detection levels and hysteresis characteristic are easily actualized.

Abstract: Parasitic inductance of the main circuit of a power source unit is reduced. In a non-insulated DC-DC converter having a circuit in which a power MOSFET for high side switch and a power MOSFET for low side switch are connected in series, the power MOSFET for high side switch and the power MOSFET for low side switch are formed of n-channel vertical MOSFETs, and a source electrode of the power MOSFET for high side switch and a drain electrode of the power MOSFET for low side switch are electrically connected via the same die pad.

Abstract: A power supply capable of reducing loss of large current and high frequency. In an MCM for power supply in which a high-side power MOSFET chip, a low-side power MOSFET chip and a driver IC chip driving them are sealed in one sealing material (a capsulating insulation resin), a wiring length of a wiring DL connecting an output terminal of the driver IC chip to a gate terminal of the low-side power MOSFET chip or a source terminal is made shorter than a wiring length of a wiring DH connecting the output terminal of the driver IC chip to a gate terminal of the high-side power MOSFET chip or a source terminal. Further, the number of the wiring DL is made larger than the number of the wiring DH.

Abstract: There is provided a semiconductor device in which a wiring inductance of a DC/DC converter formed on a multi-layered wiring substrate can be reduced and the characteristics can be improved. In the semiconductor device, in an input-side capacitor, one capacitor electrode is electrically connected to a power-supply pattern between a control power MOSFET and a synchronous power MOSFET, and the other capacitor electrode is electrically connected to a ground pattern therebetween. The multi-layered wiring substrate includes: a via conductor arranged at a position of the one capacitor electrode for electrically connecting among a plurality of power-supply patterns in a thickness direction; and a via conductor arranged at a position of the other capacitor electrode for electrically connecting among a plurality of ground patterns in a thickness direction.

Abstract: A digital control switching regulator of the invention ON/OFF-controls switching elements by digital-controlled pulse width modulation signals and converts an input voltage to a desired output voltage. The switching regulator includes an input voltage detection circuit that includes: a voltage dividing circuit outputting a divided voltage of the input voltage; a comparator section comparing the divided voltage of the input voltage with a first reference voltage and a second reference voltage and outputting a first comparison signal and a second comparison signal indicating comparison results; and a control section controlling a dividing ratio of the voltage dividing circuit based on the first comparison signal and the second comparison signal to obtain the predetermined divided voltage, thereby outputting an input voltage digital signal corresponding to the input voltage. The input voltage digital signal controls controller coefficients for use in the digital control.

Abstract: Parasitic inductance of the main circuit of a power source unit is reduced. In a non-insulated DC-DC converter having a circuit in which a power MOSFET for high side switch and a power MOSFET for low side switch are connected in series, the power MOSFET for high side switch and the power MOSFET for low side switch are formed of n-channel vertical MOSFETs, and a source electrode of the power MOSFET for high side switch and a drain electrode of the power MOSFET for low side switch are electrically connected via the same die pad.

Abstract: In a power supply unit having high-side and low-side switching elements each including power MOSFETs connected in parallel, the power MOSFETs are controlled so that the number of the transistors in an off state is increased as an output current becomes lower, and particularly, the transistors turned off when the output current is low are disposed on an outer side of a loop formed from a positive terminal of an input capacitor of a printed board to a negative terminal of the input capacitor via the switching elements. Thus, by turning off packages of the power MOSFETs disposed on an outer side of the main circuit loop and turning on packages of the power MOSFETs disposed on an inner side of the loop, the parasitic inductance of a main circuit is reduced, so that the switching loss can be reduced and efficiency in a light load can be improved.

Abstract: The electrical characteristics of a semiconductor device are enhanced. In the package of the semiconductor device, there are encapsulated first and second semiconductor chips with a power MOS-FET formed therein and a third semiconductor chip with a control circuit for controlling their operation formed therein. The bonding pads for source electrode of the first semiconductor chip on the high side are electrically connected to a die pad through a metal plate. The bonding pad for source electrode of the second semiconductor chip on the low side is electrically connected to lead wiring through a metal plate. The metal plate includes a first portion in contact with the bonding pad of the second semiconductor chip, a second portion extended from a short side of the first portion to the lead wiring, and a third portion extended from a long side of the first portion to the lead wiring.

Abstract: A digital control switching power supply unit includes an A/D converter circuit having a delay line circuit that has a delay element array whose delay time is controlled by a bias current, and that converts a current value into a digital signal using a signal transmission delay time, a phase difference detector circuit that detects a phase difference between a switching cycle and an A/D conversion cycle, a charge pump circuit that generates a control voltage in accordance with the phase difference, and a bias current indicator circuit that determines a bias current in accordance with an output voltage of the charge pump circuit and a result of a comparison of a detected value of the output voltage and a reference voltage, wherein the digital control switching power supply unit controls in such a way that the A/D conversion cycle is synchronized with the switching cycle.

Abstract: The electrical characteristics of a semiconductor device are enhanced. In the package of the semiconductor device, there are encapsulated first and second semiconductor chips with a power MOS-FET formed therein and a third semiconductor chip with a control circuit for controlling their operation formed therein. The bonding pads for source electrode of the first semiconductor chip on the high side are electrically connected to a die pad through a metal plate. The bonding pad for source electrode of the second semiconductor chip on the low side is electrically connected to lead wiring through a metal plate. The metal plate includes a first portion in contact with the bonding pad of the second semiconductor chip, a second portion extended from a short side of the first portion to the lead wiring, and a third portion extended from a long side of the first portion to the lead wiring.

Abstract: A digital control switching power supply unit converts an input voltage into a desired output voltage using a digitally controlled pulse width modulation (PWM) signal according to a switching cycle. The power supply unit includes an analog-to-digital converter (ADC). The ADC converts a result of a comparison between an output voltage and a reference voltage to a digital signal during a conversion cycle. The ADC includes a circuit for outputting a phase difference between a switching cycle and the conversion cycle, and a delay circuit. The delay circuit generates a delay output current based on a result of the comparison and the phase difference and determines the conversion time delay according to the delay output current. The delay circuit also generates a delay reference current based on the reference voltage and the phase difference and determining the duration of the conversion cycle according to the delay reference current.

Abstract: The present invention provides a process for producing 2?,3?-didehydro-3?-deoxy-4?-ethynylthymidine, which is useful as a medicine, in an efficient and industrially advantageous manner, and more specifically, provides a process for producing 2?,3?-didehydro-3?-deoxy-4?-ethynylthymidine as shown below. (wherein R1 and R2 independently represent a protective group for a hydroxy group, or R1 and R2 together form a protective group for two hydroxy groups, R3 and R4 independently represent a protective group for a hydroxy group, R5 represents a protective group for a hydroxy group, R6 represents a protective group for a hydroxy group, X represents a leaving group, and Y represents a halogen atom.

Abstract: A semiconductor device capable of reducing an inductance is provided. In the semiconductor device in which a rectification MOSFET, a commutation MOSFET, and a driving IC that drives these MOSFETs are mounted on one package, the rectification MOSFET, a metal plate, and the commutation MOSFET are laminated. A current of a main circuit flows from a back surface of the package to a front surface thereof. The metal plate is connected to an output terminal via a wiring in the package. Wire bondings are used for wirings for connecting the driving IC, the rectification MOSFET, and the commutation MOSFET, all terminals being placed on the same plane. For this reason, the inductance becomes small and also a power source loss and a spike voltage are reduced.