Ricoh Company, Ltd.

Hideki Agari

Kohji Yoshii

Toshihisa Nagata

Hirohisa Abe

Keiji Fukumura

Yohichi Sakai

Tsugunori Okuda

Hironobu Agari

Kazuhiko Suzuki

Kohiji Yoshii

A constant voltage circuit is disclosed that includes an output control transistor and an overcurrent protection circuit. The overcurrent protection circuit includes a proportional current generation circuit part, a current division circuit part, a division ratio control circuit part, a current-voltage conversion circuit part, and an output current control circuit part. When the output voltage of the current-voltage conversion circuit part reaches a predetermined voltage, the output current control circuit part prevents an increase in the output current of the output control transistor so as to reduce a voltage output from an output terminal. When the voltage output from the output terminal is reduced to a predetermined limit voltage, the division ratio control circuit part changes the division ratio of the current division circuit part so that a current supplied to the current-voltage conversion circuit part increases so as to reduce the output current of the output control transistor.

Constant voltage circuit

A semiconductor package includes an IC chip including a pad array having at least four pads, the pads including a voltage input pad and a voltage output pad disposed at edges of the pad array, a driver transistor disposed between the voltage input pad and the voltage output pad to receive an input voltage from the voltage input pad and output an output voltage to the voltage output pad, disposed in contact with an outer edge of the element arrangement region; and at least four leads on which the IC chip is mounted by flip chip bonding, disposed corresponding to the pads, formed in a lead array, the leads including a voltage input lead electrically connected to the voltage input pad and a voltage output lead electrically connected to the voltage output pad, disposed at edges of the lead array.

Semiconductor package and electronic component package

A power supply circuit includes a first voltage regulator, a second voltage regulator, and a voltage comparator. The first voltage regulator is connected to a direct current power supply, and regulates a direct current supply voltage down to a first voltage level to output a first voltage at a first output terminal. The second voltage regulator is connected to the first voltage regulator, and regulates the first output voltage down to a constant, second voltage level to output a second voltage at a second output terminal. The voltage comparator is connected to the first and second voltage regulators, compares the first output voltage against a given threshold level greater than the second voltage level, and deactivates the second voltage regulator until the first output voltage exceeds the given threshold level upon startup of the power supply circuit.

Power supply circuit

An integrated circuit for supplying power includes an IC chip having a rectangular shape and having a first edge and a second edge opposite the first edge, a switching regulator implemented on the IC chip and having a driver transistor whose ON time of switching is controlled to adjust an output voltage of the switching regulator, and a series regulator implemented on the IC chip, wherein the driver transistor of the switching regulator is positioned near the first edge, and the series regulator is positioned near the second edge.

Power supply IC having switching regulator and series regulator

A voltage regulator is disclosed. The voltage regulator includes an output unit for converting an input voltage provided by a power source into a predetermined voltage, and for outputting the converted voltage, a monitoring unit for determining whether the input voltage provided by the power source is greater than a reference voltage, and a step-up unit for stepping up the input voltage provided by the power source if the monitoring unit determines that the input voltage is less than the reference voltage. The output unit includes a converting unit for converting the stepped-up voltage into the predetermined voltage.

Voltage regulator including an output unit for converting input voltage into a predetermined voltage and for outputting the converted voltage

A semiconductor apparatus is disclosed. The semiconductor apparatus comprises a substrate with a pad, an internal circuitry region, and a protection resistance formed on the substrate. The pad is connected to a first electrode of the protection resistance by wiring, the internal circuitry region is connected to a second electrode of the protection resistance by wiring, and the protection resistance protects the internal circuitry region from electrostatic discharging. The semiconductor apparatus is characterized in that the pad is placed between the protection resistance and the internal circuitry region.

Semiconductor apparatus

A constant-voltage circuit includes a switching regulator and a series regulator each configured to start operating according to a selection signal input from outside the integrated circuit for exclusively causing one of the switching or the series regulators to operate, convert an input voltage to a rated voltage and to output the voltage to an output terminal. The switching regulator performs a soft-start operation for raising an output voltage to the rated voltage at a constant speed when starting operation. The series regulator regulates a current so that an output current does not exceed a predetermined value, simultaneously starts operating when the switching regulator starts operating, and automatically stops outputting a current to the output terminal when the soft-start operation is completed. A semiconductor apparatus provided with a predetermined function includes the constant-voltage circuit. A control method controls the constant-voltage circuit.

Constant-voltage circuit capable of reducing time required for starting, semiconductor apparatus including constant-voltage circuit, and control method of constant-voltage circuit

A disclosed power supply circuit () for receiving an input voltage at an input terminal (VDD), converting the input voltage to an output voltage and outputting the output voltage to a load () connected to an output terminal (OUT), comprises: a power supply circuit unit () for converting the input voltage to a predetermined constant voltage and outputting the converted voltage to the output terminal, the power supply circuit unit operating in accordance with a first control signal (CE); an output current detecting circuit unit () for detecting a current output (iout) from the power supply circuit unit, and outputting a second control signal when the detected current is smaller than a predetermined value i; and an output voltage detecting circuit unit () for detecting a voltage output (Vout) from the power supply circuit unit, and operating while the output current detecting circuit unit outputs the second control signal, the output voltage detecting circuit unit stopping operation of the power supply circuit unit with the first control signal when the detected voltage exceeds a predetermined value Vdet; whereby the output supply voltage detecting circuit unit makes the power supply circuit unit operate when the detected voltage becomes equal to or lower than a predetermined value Vdetthat is lower than the predetermined value Vdet, and thereby the power supply circuit unit performs intermittent operations.

The present invention relates to a power supply circuit that can intermittently operate when its load is small and therefore can reduce current consumption at a sleep mode. The power supply circuit for receiving an input voltage at an input terminal, converting the input voltage to an output voltage and outputting the output voltage to a load connected to an output terminal comprises: a power supply circuit unit; an output current detecting circuit unit; and an output voltage detecting circuit unit; whereby the output supply voltage detecting circuit unit makes the power supply circuit unit operate when the detected voltage becomes equal to or lower than a predetermined value, and thereby the power supply circuit unit performs intermittent operations.

A direct current power supply apparatus includes a first power supply circuit and a second power supply circuit. The first power supply circuit converts a source voltage from an externally supplied direct current power source into a first voltage and provides the first voltage to an output terminal. The second power supply circuit converts the source voltage from the externally supplied direct current power source into a second voltage and provides the second voltage to the output terminal. The second power supply circuit is controlled to be turned on and off. The first power supply circuit detects voltage at the output terminal and, when the second voltage is not being provided because the second power supply circuit is inactivated, provides the first voltage.

Power supplying methods and apparatus that provide stable output voltage

A voltage regulator, which generates and outputs a given voltage based on a preset reference voltage, includes: a detection circuit part detecting the output voltage and generating and outputting a voltage based on the detected voltage; first and second operational amplifiers each comparing the output voltage of said detection circuit part and the preset reference voltage and outputting a voltage representing a comparison result, the first operational amplifier being controlled based on control signals supplied externally and consuming a larger amount of electric current than the second operational amplifier; and an output circuit part comprising an output transistor outputting an electric current based on the output voltages of the first and second operational amplifiers.

Growing community of inventors

Osaka, Japan

Hideki Agari