Abstract: A current detection circuit includes: at least one current detector configured to detect a current flowing through a second switch element of at least one switching output stage configured to connect a first switch element and the second switch element in series; an analog signal generator configured to generate an analog signal corresponding to the current detected by the at least one current detector; a converter configured to receive the analog signal, convert the analog signal to a digital signal corresponding to an integrated value of the analog signal, and output the digital signal; and a corrector configured to correct any one of a drive voltage, an input, and an output of the converter according to an on-DUTY of the second switch element.

Abstract: The disclosure relates to a semiconductor device and a step-down multi-phase DC/DC converter. A DC/DC converter having higher load response performance and efficiency is provided. The step-down multi-phase DC/DC converter includes multiple output-stage circuits, which generate multiple switch voltages in rectangular waves by means of switching an input voltage, and an output voltage is obtained by means of rectifying and smoothing the multiple switch voltages. An error voltage is generated on the basis of a feedback voltage corresponding to the output voltage and a reference voltage, multiple feedback pulsating voltages variant with the multiple switch voltages are generated on the basis of the feedback voltage, and an on timing sequence including multiple on timings is generated according to the generated voltages. The multiple output circuits are switch-driven sequentially according to the on timing sequence, so as to set phase differences for the switch-driving.

Abstract: The disclosure relates to a semiconductor device and a step-down multi-phase DC/DC converter. A DC/DC converter having higher load response performance and efficiency is provided. The step-down multi-phase DC/DC converter includes multiple output-stage circuits, which generate multiple switch voltages in rectangular waves by means of switching an input voltage, and an output voltage is obtained by means of rectifying and smoothing the multiple switch voltages. An error voltage is generated on the basis of a feedback voltage corresponding to the output voltage and a reference voltage, multiple feedback pulsating voltages variant with the multiple switch voltages are generated on the basis of the feedback voltage, and an on timing sequence including multiple on timings is generated according to the generated voltages. The multiple output circuits are switch-driven sequentially according to the on timing sequence, so as to set phase differences for the switch-driving.

Abstract: In a normal state in which a main power supply supplies an input voltage having a first level, a step-down converter is enabled. In this state, the step-down converter steps down the input voltage and supplies a power supply voltage having a second level to a load. In the normal state, a step-up converter is operated in a forward direction. In this state, the step-up converter steps up the power supply voltage so as to charge a backup capacitor using a voltage having a third level. In a power supply disconnection state in which a disconnection of the input voltage occurs, the step-up converter is operated in a reverse direction. In this state, the step-up converter steps down a capacitor voltage across the backup capacitor, and supplies the power supply voltage having the second voltage level to the load.

Abstract: A control circuit of a DC/DC converter includes: a driver turning on a switching transistor and turning off a rectifying transistor in on state, turning off the switching transistor and turning on the rectifying transistor in off state, and turning off the switching transistor and turning off the rectifying transistor in high impedance state; and a switching controller controlling the on state, the off state and the high impedance state, wherein the switching controller repeats a process including: transitioning to the off state when predetermined condition is satisfied in the on state; transitioning to the high impedance state with zero-cross of coil current flowing into an inductor as trigger in the off state; measuring variable time per cycle and transitioning to the off state with time-up as trigger; and transitioning to the on state when feedback voltage corresponding to output voltage of the DC/DC converter decreases to lower threshold voltage.

Abstract: First bumps and second bumps are arranged on a substrate. Top surfaces in a desired positional relationship are formed by pressing the bumps by a pressing member at the same time. An image pickup element is bonded to the first bumps and a sensor cover is bonded to the second bumps.

Abstract: A control circuit of a DC/DC converter includes: a driver turning on a switching transistor and turning off a rectifying transistor in on state, turning off the switching transistor and turning on the rectifying transistor in off state, and turning off the switching transistor and turning off the rectifying transistor in high impedance state; and a switching controller controlling the on state, the off state and the high impedance state, wherein the switching controller repeats a process including: transitioning to the off state when predetermined condition is satisfied in the on state; transitioning to the high impedance state with zero-cross of coil current flowing into an inductor as trigger in the off state; measuring variable time per cycle and transitioning to the off state with time-up as trigger; and transitioning to the on state when feedback voltage corresponding to output voltage of the DC/DC converter decreases to lower threshold voltage.

Abstract: A control circuit of a DC/DC converter is disclosed. The control circuit includes a pulse modulator generating a comparison pulse, which is transitioned to an on level when a feedback voltage depending on an output voltage of the converter is lowered to a threshold voltage and then transitioned to an off level; a peak current detector asserting a detection signal when a coil current of the converter reaches a predetermined peak current; a logic part generating a control pulse which is transitioned to an on level when the comparison pulse is transitioned to the on level, and is transitioned to an off level at a time which is later among the time when the comparison pulse is transitioned to the off level and the time when the peak current detection signal is asserted; and a driver switching a switching transistor of the converter based on the control pulse.

Abstract: A control circuit for controlling a switching transistor and a synchronous rectifying transistor of a switching regulator includes: a bottom detection comparator configured to assert an on signal; a timer circuit configured to generate an off signal; a zero current detector configured to assert a zero current detection signal; and a driving circuit configured to receive the on signal, the off signal and the zero current detection signal, and (i) turn on the switching transistor and turn off the synchronous rectifying transistor when the on signal is asserted, (ii) turn off the switching transistor and turn on the synchronous rectifying transistor when the off signal is asserted, and (iii) turn off the switching transistor and the synchronous rectifying transistor when the zero current detection signal is asserted.

Abstract: A control circuit for controlling a switching transistor of a switching regulator includes a hysteresis comparator circuit comparing a feedback voltage according to an output signal of the switching regulator with a reference voltage and a threshold voltage and outputting a pulse width modulation signal as an output signal of the hysteresis comparator circuit, where the threshold voltage has a hysteresis according to the pulse width modulation signal. The control circuit further includes a driver driving the switching transistor based on the pulse width modulation signal, a phase comparator generating a phase difference signal based on a phase difference between a reference clock signal and a pulse signal corresponding to the pulse width modulation signal, and a loop filter generating a control voltage by filtering the phase difference signal. The hysteresis comparator circuit is further configured to control a response speed thereof depending on the control voltage.

Abstract: A control circuit of a step-up/step-down DC/DC converter includes: a hysteresis comparator configured to receive a feedback voltage and a reference voltage, compare the feedback voltage with a threshold voltage corresponding to the reference voltage, and generate a pulse signal indicating a result of the comparison; a logic unit configured to fix a second switching transistor at an OFF state and switch a first switching transistor based on the pulse signal in a step-down mode and fix the first switching transistor at an ON state and switch the second switching transistor based on the pulse signal in a step-up mode.

Abstract: A control circuit for controlling a switching transistor and a synchronous rectifying transistor of a switching regulator includes: a bottom detection comparator configured to assert an on signal; an off signal generator configured to assert an off signal; a zero current detector configured to assert a zero current detection signal; and a control logic part configured to receive the on signal, the off signal and the zero current detection signal and generate a control signal such that the control circuit (i) transitions to a first state where, when the on signal is asserted, (ii) transitions to a second state where, when the off signal is asserted, and (iii) transitions to a third state where, when the zero current detection signal is asserted; In the third state, the control logic part reduces an operation current of at least a portion of the control circuit.

Abstract: A control circuit of a DC/DC converter is disclosed. The control circuit includes a pulse modulator generating a comparison pulse, which is transitioned to an on level when a feedback voltage depending on an output voltage of the converter is lowered to a threshold voltage and then transitioned to an off level; a peak current detector asserting a detection signal when a coil current of the converter reaches a predetermined peak current; a logic part generating a control pulse which is transitioned to an on level when the comparison pulse is transitioned to the on level, and is transitioned to an off level at a time which is later among the time when the comparison pulse is transitioned to the off level and the time when the peak current detection signal is asserted; and a driver switching a switching transistor of the converter based on the control pulse.

Abstract: A control circuit of a step-up/step-down DC/DC converter includes: a hysteresis comparator configured to receive a feedback voltage and a reference voltage, compare the feedback voltage with a threshold voltage corresponding to the reference voltage, and generate a pulse signal indicating a result of the comparison; a logic unit configured to fix a second switching transistor at an OFF state and switch a first switching transistor based on the pulse signal in a step-down mode and fix the first switching transistor at an ON state and switch the second switching transistor based on the pulse signal in a step-up mode.

Abstract: A control circuit for controlling a switching transistor and a synchronous rectifying transistor of a switching regulator includes: a bottom detection comparator configured to assert an on signal; an off signal generator configured to assert an off signal; a zero current detector configured to assert a zero current detection signal; and a control logic part configured to receive the on signal, the off signal and the zero current detection signal and generate a control signal such that the control circuit (i) transitions to a first state where, when the on signal is asserted, (ii) transitions to a second state where, when the off signal is asserted, and (iii) transitions to a third state where, when the zero current detection signal is asserted; In the third state, the control logic part reduces an operation current of at least a portion of the control circuit.

Abstract: A control circuit for controlling a switching transistor and a synchronous rectifying transistor of a switching regulator includes: a bottom detection comparator configured to assert an on signal; a timer circuit configured to generate an off signal; a zero current detector configured to assert a zero current detection signal; and a driving circuit configured to receive the on signal, the off signal and the zero current detection signal, and (i) turn on the switching transistor and turn off the synchronous rectifying transistor when the on signal is asserted, (ii) turn off the switching transistor and turn on the synchronous rectifying transistor when the off signal is asserted, and (iii) turn off the switching transistor and the synchronous rectifying transistor when the zero current detection signal is asserted.

Abstract: A control circuit for controlling a switching transistor of a switching regulator includes a hysteresis comparator circuit comparing a feedback voltage according to an output signal of the switching regulator with a reference voltage and a threshold voltage and outputting a pulse width modulation signal as an output signal of the hysteresis comparator circuit, where the threshold voltage has a hysteresis according to the pulse width modulation signal. The control circuit further includes a driver driving the switching transistor based on the pulse width modulation signal, a phase comparator generating a phase difference signal based on a phase difference between a reference clock signal and a pulse signal corresponding to the pulse width modulation signal, and a loop filter generating a control voltage by filtering the phase difference signal. The hysteresis comparator circuit is further configured to control a response speed thereof depending on the control voltage.

Abstract: According to the invention, as an input voltage of a certain step-up unit of a plurality of stages of step-up units, a stepped-up output of a step-up unit in a stage preceding the certain step-up unit is inputted. This makes it possible to increase the level of a voltage stepped up by each step-up unit, and reduce the number of units. Furthermore, according to the invention, when an output voltage of a step-up unit that performs stepping-up operation according to a reference constant current is lower than a reference voltage, a reference constant current is produced; when the output voltage thereof exceeds the reference voltage, the reference constant current is stopped. This makes it possible to provide stable output of an output voltage at a predetermined level, and reduce an inrush current during start-up to a predetermined current level.

Abstract: A step-up power supply unit for providing a multiplicity of different step-up voltages as needed, generated by stepping up a voltage of a single power source such as a battery. The step-up voltage of the last stage charge pump unit and the step-up voltage of at least one charge pump unit other than the last stage charge pump unit, are made available as multiple output voltages. When one or more of the output voltages are not needed, all the charge pump units subsequent to the one providing the highest output voltage are disabled based on an output voltage control signal, thereby minimizing the size and cost of the step-up circuit and reducing the power consumption by the circuit.

Abstract: According to the invention, as an input voltage of a certain step-up unit of a plurality of stages of step-up units, a stepped-up output of a step-up unit in a stage preceding the certain step-up unit is inputted. This makes it possible to increase the level of a voltage stepped up by each step-up unit, and reduce the number of units. Furthermore, according to the invention, when an output voltage of a step-up unit that performs stepping-up operation according to a reference constant current is lower than a reference voltage, a reference constant current is produced; when the output voltage thereof exceeds the reference voltage, the reference constant current is stopped. This makes it possible to provide stable output of an output voltage at a predetermined level, and reduce an inrush current during start-up to a predetermined current level.