Abstract: An integrated circuit includes an amplifier configured to amplify an analog signal, and an offset adjustment circuit that is provided in a stage prior to the amplifier and that is configured to adjust an offset amount of the analog signal to be amplified by the amplifier.

Abstract: A signal processing circuit includes a first sampling capacitor and a second sampling capacitor that are connected for an input signal path of an analog signal, and a signal processor configured to perform predetermined processing on the analog signal sampled by the first sampling capacitor and the analog signal sampled by the second sampling capacitor. The sampling of the analog signal transmitted to one capacitor of the first sampling capacitor and the second sampling capacitor, and the predetermined processing performed by the signal processor on the analog signal sampled by another capacitor of the first sampling capacitor and the second sampling capacitor can be performed in parallel.

Abstract: A DC-DC converter, which allows a current to pass through an inductor and rectifies the current through the inductor to convert an input direct current voltage supplied from a direct current power unit into a direct current voltage at a different potential and output the direct current voltage, includes a switching control circuit performing peak-current control procedures including turning on the switching element when the converted direct current voltage drops to a predetermined potential and turning off the switching element when the current through the inductor reaches a predetermined value. The converter includes a copied-current generating circuit generating a current proportional to the output current. The switching control circuit turns off the switching element when the circuit detects that the current through the inductor reaches a predetermined value with reference to a combined current of the copied current generated at the copied-current generating circuit and a predetermined reference current.

Abstract: A DC-DC converter, which allows a current to pass through an inductor and rectifies the current through the inductor to convert an input direct current voltage supplied from a direct current power unit into a direct current voltage at a different potential and output the direct current voltage, includes a switching control circuit performing peak-current control procedures including turning on the switching element when the converted direct current voltage drops to a predetermined potential and turning off the switching element when the current through the inductor reaches a predetermined value. The converter includes a copied-current generating circuit generating a current proportional to the output current. The switching control circuit turns off the switching element when the circuit detects that the current through the inductor reaches a predetermined value with reference to a combined current of the copied current generated at the copied-current generating circuit and a predetermined reference current.

Abstract: A ripple-control switched-mode power supply includes a control circuit to switch on/off a drive switching element. The control circuit includes a simulated voltage generation circuit that smoothes a voltage at a node connecting the drive switching element and an inductor and that generates a simulated voltage corresponding to an output voltage; a timer that measures a time corresponding to an input voltage and the simulated voltage; a voltage comparison circuit that compares a feedback voltage and a predetermined voltage; and a control pulse generation circuit that generates a control pulse having a pulse width corresponding to the time based on outputs from the timer and the voltage comparison circuit. The control circuit varies the pulse width of the control pulse in accordance with a variation in the input voltage to maintain a constant switching cycle.

Abstract: Disclosed is a switched-mode power supply including an inductor which is connected between a voltage input terminal to which a DC voltage is input and an output terminal to which a load is connected, a driver switching element which intermittently feeds a current to the inductor and a control circuit which generates a control pulse according to a feedback voltage from output side and controls on/off of the driver switching element. The control circuit includes a voltage comparison circuit which compares the feedback voltage to a predetermined voltage and a pseudo ripple generator circuit which generates a pseudo ripple voltage having a predetermined amplitude, and the control circuit injects a ripple component in a transmission path of the feedback voltage based on the pseudo ripple voltage generated by the pseudo ripple generator circuit.

Abstract: Disclosed is a switching-mode power supply device which outputs a voltage having a different electrical potential from an input voltage including an inductor, a driving switching element and a control circuit, and the control circuit includes a trigger signal generating circuit which generates and outputs a signal which provides timing to turn the driving switching element on or off, a first timekeeping unit which times a fixed ON period or a fixed OFF period which defines the pulse width of a driving pulse of the driving switching element, a second timekeeping unit which times a minimum OFF period or a minimum ON period of the driving switching element and a sudden load change detection circuit which detects a sudden load change.

Abstract: A control technology which eliminates the need for changing the switching frequency even under light load where the on-time of a drive switching element becomes shorter than a minimum on-time dependent on the characteristics of the circuit in a synchronous rectification switching regulator. The synchronous rectification switching regulator includes a drive switching element for storing energy in a coil by applying a DC input voltage from a DC power supply to an inductor and permitting a current to flow, and a rectification switching element for rectifying the current of the inductor during an energy discharge period where the drive switching element is turned off. The timing for turning off the rectification switching element under light load is delayed so as to store energy in the inductor from the output, and the on-time is controlled to become longer as the load becomes lighter by the output from an error amplifier.

Abstract: Provided is a switched-mode power supply. The power supply includes: a DC voltage input terminal; a driver switching element connected to the input terminal; an inductor connected to the driver switching element; an output terminal connected to the inductor and outputting output voltage different from the input voltage; and an integrated circuit outputting control pulses used for on-off control of the driver switching element. The integrated circuit has: a ripple injection circuit adding a ripple component to a feedback voltage of the output voltage; a voltage comparator comparing the summed voltage with a predetermined voltage; and a control pulse generator generating the control pulse based on an output of the voltage comparator. The ripple injection circuit has an integrator outputting an integral of the voltage at the node between the driver switching element and the inductor, and a series RC circuit connected to the output end of the integrator.

Abstract: A ripple-control switched-mode power supply includes a control circuit to switch on/off a drive switching element. The control circuit includes a simulated voltage generation circuit that smoothes a voltage at a node connecting the drive switching element and an inductor and that generates a simulated voltage corresponding to an output voltage; a timer that measures a time corresponding to an input voltage and the simulated voltage; a voltage comparison circuit that compares a feedback voltage and a predetermined voltage; and a control pulse generation circuit that generates a control pulse having a pulse width corresponding to the time based on outputs from the timer and the voltage comparison circuit. The control circuit varies the pulse width of the control pulse in accordance with a variation in the input voltage to maintain a constant switching cycle.

Abstract: Disclosed is a switched-mode power supply including an inductor which is connected between a voltage input terminal to which a DC voltage is input and an output terminal to which a load is connected, a driver switching element which intermittently feeds a current to the inductor and a control circuit which generates a control pulse according to a feedback voltage from output side and controls on/off of the driver switching element. The control circuit includes a voltage comparison circuit which compares the feedback voltage to a predetermined voltage and a pseudo ripple generator circuit which generates a pseudo ripple voltage having a predetermined amplitude, and the control circuit injects a ripple component in a transmission path of the feedback voltage based on the pseudo ripple voltage generated by the pseudo ripple generator circuit.

Abstract: Disclosed is a switching-mode power supply device which outputs a voltage having a different electrical potential from an input voltage including an inductor, a driving switching element and a control circuit, and the control circuit includes a trigger signal generating circuit which generates and outputs a signal which provides timing to turn the driving switching element on or off, a first timekeeping unit which times a fixed ON period or a fixed OFF period which defines the pulse width of a driving pulse of the driving switching element, a second timekeeping unit which times a minimum OFF period or a minimum ON period of the driving switching element and a sudden load change detection circuit which detects a sudden load change.

Abstract: A level shift circuit includes a level changing unit which includes first and second MOS transistors connected in series between a first power supply voltage terminal and a grounding point, and receives a signal having a first amplitude which varies between a lower second voltage and a ground potential to convert the signal to a signal having a second amplitude, and an output stage which includes first and second MOS transistors connected in series between the first power supply voltage terminal and a third voltage terminal to which a third voltage lower than the first power supply voltage and higher than the ground potential is supplied, and which stage is connected to an output node of the level changing unit. A first MOS transistor is connected in series between the first MOS transistor and the second MOS transistor of the level changing unit.

Abstract: There is provided a PWM comparator which needs no current detecting differential amplifier in a control circuit constituting a current mode control DC/DC converter. The comparator includes a differential input stage including two pairs of input differential transistors whose sources are commonly connected for each pair; two constant-current sources connected to the common sources of the pairs of input differential transistors, respectively; a load transistor commonly connected to drain sides of the pairs and performing a current-voltage conversion; and an output stage connected to a point where the differential input stage and the load transistor are connected to each other. A feedback voltage of an output voltage and a slope compensating waveform signal are input to terminals, respectively, of one pair, and voltages at both ends of a current detecting resistor, which is connected in series to the inductor, are input to terminals, respectively, of the other pair.

Abstract: A control technology which eliminates the need for changing the switching frequency even under light load where the on-time of a drive switching element becomes shorter than a minimum on-time dependent on the characteristics of the circuit in a synchronous rectification switching regulator. The synchronous rectification switching regulator includes a drive switching element for storing energy in a coil by applying a DC input voltage from a DC power supply to an inductor and permitting a current to flow, and a rectification switching element for rectifying the current of the inductor during an energy discharge period where the drive switching element is turned off. The timing for turning off the rectification switching element under light load is delayed so as to store energy in the inductor from the output, and the on-time is controlled to become longer as the load becomes lighter by the output from an error amplifier.

Abstract: In a current resonance type multi-phase DC/DC converting apparatus for combining, using an output capacitor, M converter output voltages produced by M current resonance type multi-phase DC/DC converters connected in parallel to each other to produce an output voltage, each of the M current resonance type multi-phase DC/DC converters has N current resonance type DC/DC converters connected in parallel with one another. The N current resonance type DC/DC converters have N resonance circuits, respectively. Each of the M current resonance type multi-phase DC/DC converters shares a resonance inductor of the N resonance circuits.

Abstract: In a current resonance type multi-phase DC/DC converting apparatus for combining, using an output capacitor, M converter output voltages produced by M current resonance type multi-phase DC/DC converters connected in parallel to each other to produce an output voltage, each of the M current resonance type multi-phase DC/DC converters has N current resonance type DC/DC converters connected in parallel with one another. The N current resonance type DC/DC converters have N resonance circuits, respectively. Each of the M current resonance type multi-phase DC/DC converters shares a resonance inductor of the N resonance circuits.