Rohm Co., Ltd.

Isao Takobe

Yuhei Yamaguchi

Takeshi Nagata

Tetsuo Tateishi

Shingo Hashiguchi

Masashi Nagasato

Akihiro Kawano

Hironori Sumitomo

Yukihiro Watanabe

Keita Itohara

Kosuke Sato

Masahiro Osa

Disclosed is a control circuit of a switched capacitor converter, the switched capacitor converter including a plurality of capacitors and a plurality of switching elements, the control circuit including a control unit configured to control switching of the plurality of switching elements, and a charging unit configured to charge at least some of the plurality of capacitors such that a potential difference across each of the at least some of the plurality of capacitors becomes equal to or more than a voltage lower limit set value, and the control unit being configured to start the switching after charging by the charging unit is completed.

Control circuit, switched capacitor converter, and vehicle

A level shifter includes first to third signal generators, wherein the first and second signal generators use, as an upper-side power supply voltage, a first internal voltage based on a first voltage when the first voltage is higher than a second voltage, and a second internal voltage based on the second voltage when the second voltage is higher than the first voltage, wherein the third signal generator uses the second voltage as an upper-side power supply voltage, wherein the first signal generator uses, as a lower-side power supply voltage, a third internal voltage based on a third voltage when the third voltage is higher than a fourth voltage, and a fourth internal voltage based on the fourth voltage when the fourth voltage is higher than the third voltage, and wherein the third voltage is lower than the first voltage and the fourth voltage is lower than the second voltage.

Level shifter, drive circuit, switching power supply device, and vehicle

Disclosed is a switch circuit including a switch unit including at least one switching element, and a balance circuit provided for the switch unit, the balance circuit being configured to inhibit a potential difference across the switch unit from exceeding a threshold value.

Switch circuit, switched capacitor converter, and vehicle

A linear power supply circuit includes an output transistor provided between an input terminal to which an input voltage is applied and an output terminal to which an output voltage is applied, and a driver configured to drive the output transistor based on the difference between a voltage based on the output voltage and a reference voltage. The driver includes a differential amplifier, a converter, and a first capacitor provided between the output of the differential amplifier and a ground potential. The linear power supply circuit further includes a source follower circuit including a first transistor, and moreover includes a second transistor connected in series with the output transistor and constituting together with the first transistor a current mirror circuit, and a second capacitor connected to the control terminal of the first transistor.

Linear power supply circuit and source follower circuit

An output feedback control circuit includes, for example, a first amplifier configured to generate a first error signal commensurate with a difference between an output voltage, which is fed to a load, or a feedback voltage commensurate therewith and a reference voltage, a second amplifier configured to be faster than the first amplifier and to generate a second error signal commensurate with a difference between the output voltage or the feedback voltage and the first error signal (or the reference voltage), a calculator configured to superimpose a remote sense signal, which is derived from a grounded terminal of the load, on the reference voltage, which is fed to the first amplifier, and a capacitor connected between an application terminal for the first error signal and an application terminal for the remote sense signal.

Output feedback control circuit and switching power supply

An output feedback control circuit includes, as a means for generating an error signal ERR between a feedback voltage FB commensurate with an output voltage and a reference voltage REF (means for substituting for a single error amplifier), a first signal processor (for example, an amplifier) that forms a first path, and a second signal processor (for example, an amplifier) that forms a second path. The amplifieris more accurate than the amplifier, and the amplifieris faster than the amplifier. To the output terminal of the amplifier, preferably, a capacitor Cc other than a parasitic element is connected. To the output terminal of the amplifier, preferably, no capacitor other than a parasitic element is connected, and a resistor Rc is connected. Preferably, the amplifierhas a transconductance gm1, and the amplifierhas a transconductance gm2 (≠gm1).

Output feedback control circuit and switching power supply including the same

A switching power supply device includes a first switch with a first terminal connectable to an application terminal for the input voltage and a second terminal connectable to the first terminal of an inductor; a second switch with a first terminal connectable to the first terminal of the inductor and a second terminal connectable to an application terminal for a voltage lower than the input voltage; a third switch with a first terminal connectable to the first terminal of the inductor and a second terminal connectable to the second terminal of the inductor; a detector; and a controller. The controller produces, after occurrence or a sign of occurrence of an overshoot in the output voltage is detected by the detector until settlement of the overshoot in the output voltage, a control state in which to keep the first and second switches off and the third switch on.

Switching power supply device

A linear power supply circuit according to the present invention is provided with: an output transistor provided between an input end to which an input voltage is applied and an output end to which an output voltage is applied; and a driver for driving the output transistor on the basis of the difference between a voltage based on the output voltage and a reference voltage. The driver is provided with: a differential amplifier for outputting a voltage according to the difference between the voltage based on the output voltage and the reference voltage; a capacitor one end of which has an output of the differential amplifier applied thereto and the other end of which has the voltage based on the output voltage applied thereto; a converter for converting a voltage based on the output of the differential amplifier into an electrical current and outputting the electrical current; and an electrical current amplifier for amplifying the electrical current of the output of the converter. The supply voltage of the differential amplifier is a first constant voltage or the input voltage.

Linear power supply circuit

The switching power supply device includes first and second switches connected in series between an application end of an input voltage and an application end of a low voltage lower than the input voltage, and third and fourth switches connected in series between an application end of the input voltage and an application end of the low voltage, and a control unit configured to control the on/off state of each of the first to fourth switches. The first to fourth switches are configured such that an inductor is provided between a first connection node connecting the first switch and the second switch and a second connection node connecting the third switch and the fourth switch.

A linear power supply circuit, includes: output transistor between input terminal where input voltage is applied and output terminal where output voltage is applied; a driver driving the output transistor based on difference between voltage based on the output voltage and reference voltage; and phase compensation circuit, wherein the driver includes differential amplifier outputting voltage corresponding to the difference between the voltage based on the output voltage and the reference voltage, a first capacitance having one end where output of the differential amplifier is applied and the other end where ground potential is applied, a converter converting the voltage based on the output of the differential amplifier into current, and a current amplifier amplifying the current output from the converter, and wherein the phase compensation circuit lowers gain of transfer function of the linear power supply circuit and output capacitor connected to the output terminal.

A linear power supply circuit according to the present invention is provided with: an output transistor provided between an input end to which an input voltage is applied and an output end to which an output voltage is applied; a driver for driving the output transistor; and a feedback unit for feeding, back to the driver, information about an output electrical current that is output from the output end. The driver drives the output transistor on the basis of the difference between a voltage based on the output voltage and a reference voltage, as well as the information.

A linear power supply circuit is provided with: an output transistor; and a driver for driving the output transistor on the basis of the difference between a voltage based on an output voltage and a reference voltage. The driver is provided with: a differential amplifier for outputting a voltage according to the difference between the voltage based on the output voltage and the reference voltage; a capacitor one end of which has an output of the differential amplifier applied thereto and the other end of which has the voltage based on the output voltage applied thereto; a converter for converting a voltage based on the output of the differential amplifier into an electrical current and outputting the electrical current; and a current amplifier for amplifying the electrical current of the output of the converter. The supply voltage of the differential amplifier is a first constant voltage or the input voltage.

There is provided a differential amplifier including: an inverting input terminal to which a first voltage is applied; a non-inverting input terminal to which a second voltage proportional to the first voltage is applied; and an offset part configured to generate a predetermined input offset voltage between the inverting input terminal and the non-inverting input terminal.

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Kyoto, Japan

Isao Takobe