Abstract: A switch driving circuit is provided, wherein the switch driving circuit has a function of periodically updating a simultaneous OFF time prepared to soft-switch an upper switch and a lower switch of a switching output circuit, and is configured to monitor how an output power or an input power of the switching output circuit is changed depending on previous updating of the simultaneous OFF time to determine new updated contents.

Abstract: A switching power supply includes: a switching output circuit generating an output voltage from an input voltage according to ON/OFF control of an output transistor by a pulse width modulation (PWM) signal; a first voltage generating circuit generating a first voltage based on a difference between the output voltage and a predetermined reference voltage; a second voltage generating circuit generating a triangular second voltage; a comparing circuit generating a comparison signal by comparing the first voltage and the second voltage; a clock oscillating circuit generating a clock signal; and a logic circuit generating a PWM signal in response to the clock signal and the comparison signal, wherein the second voltage generating circuit generates the second voltage by adding a first slope voltage having a first slope and a second slope voltage having a second slope according to current flown through the switching output circuit.

Abstract: A switching power supply control circuit has a switching element, a smoothing circuit, and a switching control circuit configured to control the switching element. The switching control circuit includes I-V converter configured to multiply an output current flowing into the switching element by a predetermined conversion coefficient and generating an I-V conversion voltage, an amplifier configured to amplify the sum of the I-V conversion voltage and an offset voltage and generating a current detection signal, a first DAC configured to convert a digital compensation value computed from an output voltage of the smoothing circuit to an analog converted value, a first analog comparator configured to compare the current detection signal with the analog converted value and generating a first comparison result signal, and a driver configured to control the switching element on the basis of the first comparison result signal.

Abstract: A switching power supply includes: a switching output circuit generating an output voltage from an input voltage according to ON/OFF control of an output transistor by a pulse width modulation (PWM) signal; a first voltage generating circuit generating a first voltage based on a difference between the output voltage and a predetermined reference voltage; a second voltage generating circuit generating a triangular second voltage; a comparing circuit generating a comparison signal by comparing the first voltage and the second voltage; a clock oscillating circuit generating a clock signal; and a logic circuit generating a PWM signal in response to the clock signal and the comparison signal, wherein the second voltage generating circuit generates the second voltage by adding a first slope voltage having a first slope and a second slope voltage having a second slope according to current flown through the switching output circuit.

Abstract: A switch driving circuit is provided, wherein the switch driving circuit has a function of periodically updating a simultaneous OFF time prepared to soft-switch an upper switch and a lower switch of a switching output circuit, and is configured to monitor how an output power or an input power of the switching output circuit is changed depending on previous updating of the simultaneous OFF time to determine new updated contents.

Abstract: A switching power control circuit includes an analog-to-digital converter (ADC) configured to convert an analog direct current (DC) voltage into a digital voltage; a digital compensator configured to set a gain and phase characteristics of the digital voltage output from the ADC and output a digital compensation value; and a pulse generating circuit configured to generate at least one driving signal based on the digital compensation value, wherein the pulse generating circuit is switched by an ON/OFF signal for turning on or off an output of the driving signal from the pulse generating circuit and a control scheme selection signal for selecting a predetermined driving signal from the driving signal.

Abstract: A variable delay circuit, includes: an oscillation circuit unit which generates n-phase clock signals, the n-phase clock signals having a same oscillation period and phases of the n-phase clock signals being shifted by 1/n of the oscillation period, wherein n is a natural number equal to or greater than 2; and a delay circuit unit which delays an input signal by using the clock signals to generate an output signal. The delay circuit unit adjusts a delay amount using a phase difference of the clock signals as a minimum variable unit based on a delay amount setting signal.

Abstract: A switching power control circuit includes an analog-to-digital converter (ADC) configured to convert an analog direct current (DC) voltage into a digital voltage; a digital compensator configured to set a gain and phase characteristics of the digital voltage output from the ADC and output a digital compensation value; and a pulse generating circuit configured to generate at least one driving signal based on the digital compensation value, wherein the pulse generating circuit is switched by an ON/OFF signal for turning on or off an output of the driving signal from the pulse generating circuit and a control scheme selection signal for selecting a predetermined driving signal from the driving signal.

Abstract: A switching power supply control circuit has a switching element, a smoothing circuit, and a switching control circuit configured to control the switching element. The switching control circuit includes I-V converter configured to multiply an output current flowing into the switching element by a predetermined conversion coefficient and generating an I-V conversion voltage, an amplifier configured to amplify the sum of the I-V conversion voltage and an offset voltage and generating a current detection signal, a first DAC configured to convert a digital compensation value computed from an output voltage of the smoothing circuit to an analog converted value, a first analog comparator configured to compare the current detection signal with the analog converted value and generating a first comparison result signal, and a driver configured to control the switching element on the basis of the first comparison result signal.

Abstract: An optical disc drive apparatus has: a rotation angle counter cleared when the number of pulses in a frequency multiplied FG signal has reached a value corresponding to one rotation of the disc; a switching sector detector detecting polarity switching locations based on the output signal of an RF processor to clear the rotation angle counter; a switching window signal generator generating a switching window signal having a predetermined width based on the count value; a timing signal generator generating a timing signal for each sector based on the output signal of the RF processor; and a polarity switching signal generator generating a polarity switching signal based on the switching window signal and the timing signal.

Abstract: An optical disc drive apparatus has: a rotation angle counter cleared when the number of pulses in a frequency multiplied FG signal has reached a value corresponding to one rotation of the disc; a switching sector detector detecting polarity switching locations based on the output signal of an RF processor to clear the rotation angle counter; a switching window signal generator generating a switching window signal having a predetermined width based on the count value; a timing signal generator generating a timing signal for each sector based on the output signal of the RF processor; and a polarity switching signal generator generating a polarity switching signal based on the switching window signal and the timing signal.

Abstract: A disk control circuit at least reproduces a plurality of disk media having different formats. A rotation control circuit control rotation of a disk medium to be determined. A pattern detection circuit detects a data pattern, which is unique to the disk medium, among pieces of information recorded on the disk medium. A disk determination circuit counts the number of detected unique data patterns for one rotation, based on outputs of the pattern detection circuit and the rotation control circuit, and then determines the format of the disk medium based on the number of counted unique data patterns.