Abstract: A converter circuit includes a converter and a controller. The converter converts an input voltage to an output voltage. The controller receives a reference voltage, generates a slew voltage having a substantially constant first slew rate if the reference voltage changes from a first level to a second level, and controls the converter based on the slew voltage to cause the output voltage to change from a third level to a fourth level at a substantially constant second slew rate.

Abstract: A current source regulator for controlling an output device (Mp) of current source, the output device (Mp) providing an output current (Isrc) to a load. The current source regulator comprises a first feedback loop (1) and second feedback loop (2). The first feedback loop (1) includes a first sensing path to provide a first sensing signal (Is1) for comparison with a first reference to generate a first control signal. The second feedback loop (2) comprises a second sensing path to provide a second sensing signal (Is3, Is3?) for comparison with a second reference (Ib5) to generate a charging current signal (Icharge). The charging current signal (Icharge) is applied to the control signal during a transient state of the current source regulator.

Abstract: Disclosed are devices, apparatus, circuitry, components, mechanisms, modules, units, systems, and processes for controlling a power switch of a voltage regulator. A capacitor is coupled to an output of the power switch. Charge delivery circuitry is coupled to the capacitor and configured to provide a charging current to the capacitor. Charge control circuitry can be coupled to the charge delivery circuitry and configured to selectively allow the providing of the charging current to the capacitor.

Abstract: A controller for use with a power converter including a switch configured to conduct to provide a regulated output characteristic at an output of the power converter, and method of operating the same. In one embodiment, the controller includes a linear control circuit, coupled to the output, configured to provide a first control signal for the switch as a function of the output characteristic. The controller also includes a nonlinear control circuit, coupled to the output, configured to provide a second control signal for the switch as a function of the output characteristic. The controller is configured to select one of the first and second control signals for the switch in response to a change in an operating condition of the power converter.

Abstract: As for a transistor, overlapped are factors such as a variation of a gate insulation film which occurs due to a difference of a manufacturing process and a substrate used and a variation of a crystalline state in a channel forming region and thereby, there occurs a variation of a threshold voltage and mobility of a transistor. This invention provides an electric circuit which used a rectification type device in which an electric current is generated only in a single direction, when an electric potential difference was applied to electrodes at both ends of the device. Then, the invention provides an electric circuit which utilized a fact that, when a signal voltage is inputted to one terminal of the rectification type device, an electric potential of the other terminal becomes an electric potential offset only by the threshold voltage of the rectification type device.

Abstract: A power supply module is configured for converting an AC voltage to a first DC voltage and applying the first DC voltage to a load. The power supply module includes a rectifying and filtering unit, a PFC unit, a voltage transforming unit, an input port, and a switch unit. The rectifying and filtering unit rectifies the AC voltage into a primary DC voltage and filters the primary DC voltage. The PFC unit corrects a power factor of the filtered primary DC voltage. The voltage transforming unit converts the corrected primary DC voltage and generates the first DC voltage for applying the load. The input port receives a first instruction or a second instruction and generates a first signal or a second signal, respectively. The switch unit establishes or disconnects an electrical connection between the voltage transforming unit and the load according to the first signal or the second signal.

Abstract: A system and a method are disclosed for providing a dynamically configured low drop out regulator that has zero quiescent current and a fast transient response. A power supply control circuit is provided that comprises a switcher circuit and a low drop out regulator and a control signal circuit. When the output voltage of the low drop out regulator is in a steady state condition the control signal circuit generates control signals that turn off the operation of the low drop out regulator to provide zero quiescent current. When the output voltage is not in a steady state condition the control signal circuit generates control signals that turn on the operation of the low drop out regulator to provide a fast transient response.

Abstract: A freewheeling DC/DC step-down converter includes a high-side MOSFET, an inductor and an output capacitor connected between the input voltage and ground. A freewheeling clamp, which includes a freewheeling MOSFET and diode, is connected across the inductor. When the high-side MOSFET is turned off, a current circulates through the inductor and freewheeling clamp rather than to ground, improving the efficiency of the converter. The converter has softer diode recovery and less voltage overshoot and noise than conventional Buck converters and features unique benefits during light-load conditions.

Abstract: An apparatus and method for supplying power to circuits of an integrated circuit (IC) from the wasted power in low-swing high-speed differential line drivers used in the IC, is disclosed. In a high speed line driver the load resistors of the driver are connected to a power supply, either the local power supply or the receiver power supply. DC power for the driver is supplied through these resistors. A large portion of this power, supplied from the power supply is wasted in the DC set-up circuit of the differential line driver. It is proposed to use this wasted power to power selected circuits of an IC. The use of this wasted power from the drivers for powering the circuits reduces the overall power dissipation of the system.

Abstract: A procedure for triggering a load element using an electronic switch element is presented, in which voltage on the load element is controlled with a maximum specified increase. The increase does not remain constant, but is controlled via the switching procedure in dependence on the effectively occurring power loss or a value which is dependant on it (Ua/Ubat), preferably in several phases, whereby preferably at the beginning and the end of the switch-over procedure in the phase where the output voltage changes, the increase is selected as being low relative to the increase in the middle phase, since as a result, the power loss is only insignificantly raised, yet the high-frequency interferences can be noticeably dampened.

Abstract: A power source apparatus includes: a switch circuit to receive an input voltage; a control circuit to switch the switch circuit from a second state to a first state at a timing corresponding to a comparison result between a feedback voltage generated based on a first voltage corresponding to an output voltage and a reference voltage generated based on a standard voltage set in accordance with the output voltage; and a voltage generation circuit to add a compensation voltage generated by voltage-converting a time period in which the switch circuit switches from the second state to the first state to one of the first voltage and the standard voltage, to generate the feedback voltage, to add a slope voltage which changes at a slope to one of the first voltage and the standard voltage, and to generate the reference voltage.

Abstract: A power converter including a power train, a controller and a driver. The power train includes a switch that conducts for a duty cycle and provides a regulated output characteristic for the power converter, and a micromagnetic device interposed between the switch and the output of the power converter. The micromagnetic device includes a substrate, and a magnetic core layer formed over the substrate from a magnetic alloy including iron, cobalt and phosphorous. A content of the cobalt is in a range of 1.8 to 4.5 atomic percent. A content of the phosphorus is in a range of 20.1 to 30 atomic percent. A content of the iron is substantially a remaining proportion of the magnetic alloy. The controller provides a signal to control the duty cycle of the switch. The driver provides a drive signal to the switch as a function of the signal from the controller.

Abstract: A controller for use with a power converter including a switch configured to conduct to provide a regulated output characteristic at an output of the power converter, and method of operating the same. In one embodiment, the controller includes a linear control circuit, coupled to the output, configured to provide a first control signal for the switch as a function of the output characteristic. The controller also includes a nonlinear control circuit, coupled to the output, configured to provide a second control signal for the switch as a function of the output characteristic. The controller is configured to select one of the first and second control signals for the switch in response to a change in an operating condition of the power converter.

Abstract: A power supply for IGBT/FET drivers (1) that provides separated, isolated power to each IGBT/FET driver in a system wherein the power supply (1) is connected to at least one voltage controller (16) having at least one line in main power connector (14), at least one line out main power connector (15) and at least one drive signal command input (11) for connection to at least one IGBT/FET driver. The power supply (1) includes at least one power supply unit (5) in connection with at least voltage controller (16), at least one diode (2) for routing a predetermined amount of power from the at least one voltage controller (16) to at least one capacitor (3) and at least one capacitor (3) for routing said predetermined amount of power from said at least one diode (2) to said at least one voltage controller (16).

Abstract: A current source (10), comprising a bipolar transistor (1) including a control terminal and a controlled path, a first terminal on the controlled path, to which first terminal an electrical load (D1, D2) may be connected, a second terminal on the controlled path, which second terminal may be connected to a reference potential via a resistor (4), a measuring device (2) coupled to the control terminal for measuring a control current on the control terminal, a compensation device (3) coupled to the measuring device (2) and the bipolar transistor (1) in such a manner that the control current of the bipolar transistor (1) is compensated for at the first terminal of the controlled path.

Abstract: A multimode voltage regulator circuit includes a linear regulator sub-circuit configured to supply current to a load in a low-current mode, responsive to a first control signal from a first control path, as well as a switching regulator sub-circuit configured to supply current to the load in a high-current mode, responsive to a second control signal from a second control path. The circuit further comprises a shared error amplifier configured to generate an error signal based on the difference between a reference voltage and a feedback signal coupled from the load, and a switch configured to selectively route the error signal to the first control path in the low-current mode and to the second control path in the high-current mode.

Abstract: A digital multilevel memory system includes a charge pump and a voltage regulator for generating regulated high voltages for various memory operations. The charge pump may include a plurality of boost circuits to boost the output of the charge pump during a fast start up. Afterwards, the boost circuits are disabled to allow the charge pump to generate high voltages without boosting. The boost circuits may be successively enabled to boost the voltage. The boost circuits may be loadless. The voltage regulator may operate in an open loop and may include a resistive divider as a reference voltage for regulating the high voltage from the charge pump. The charge pump may include spread spectrum pump clocking to reduce electromagnetic inference for capacitor or inductor on-chip charge pumping.

Abstract: A band-gap reference voltage generation circuit and methods thereof. A band-gap reference voltage generation circuit may include a current generator configured to generate a first current and/or a second current. A band-gap reference voltage generation circuit may include a current controller including a first resistor, through which a first current may flow, a first bipolar transistor connected with a first resistor at an emitter of a first bipolar transistor and/or connected with a node at a base of a first bipolar transistor, and/or a second bipolar transistor connected with a node at a base of a second bipolar transistor. A band-gap reference voltage generation circuit may include a current controller to generate a proportional to absolute temperature current, a feedback unit to control first and second currents to be substantially equal, and a band-gap voltage output unit to generate a reference voltage in response to a PTAT current.

Abstract: Circuits and methods that improve the performance of voltage reference driver circuits and associated analog to digital converters are provided. A voltage reference driver circuit that maintains a substantially constant output voltage when a load current is modulated by an input signal is provided. The voltage reference driver circuit synchronously decouples a voltage regulation circuit from the load circuit when modulating events such as pulses caused by the load circuit during a switching interval are generated, preventing disturbance of the regulation circuitry and keeping its output voltage substantially constant.

Abstract: A multi-phase voltage regulator comprises a plurality of current supplying stages, each current supplying stage configured to supply a local output current equaling at least a portion of a load current output from the multi-phase voltage regulator; and a plurality of control circuits, each control circuit coupled to a respective one of the plurality of current supplying stages, wherein each control circuit calculates a control signal based, at least in part, on a sampled current representative of the respective local output current and a sampled current representative of a master output current. The control signal from each control circuit causes the respective current supplying stage to be disabled gradually over a first time interval if the sum of the local output current and the master output current is detected as being below a respective first predetermined level.

Abstract: A method and an apparatus are provided for balancing current for each of a plurality of similar phases of a DC/DC boost converter. The method includes the step of measuring a voltage drop of each of the plurality of similar phases at predetermined times by measuring the voltage drop across each phase switching device when current is flowing through the switch. The method also includes the steps of calculating current information for each of the plurality of similar phases in response to the voltage drop measured for each of the plurality of similar phases and balancing current for each of the plurality of similar phases in response to the current information of each of the plurality of similar phases.

Abstract: A H-bridge circuit for supplying a load with a defined current comprises a first transistor for coupling a first terminal of the load to a positive potential of a power source; a second transistor for coupling the first terminal of the load to a negative potential of the power source; a third transistor for coupling a second terminal of the load to the positive potential of the power source; and a fourth transistor for coupling the second terminal of the load to the negative potential of the power source. The circuit further comprises a current sensing circuitry for sensing a current flowing through the load and for generating a voltage signal representative of the current, and a control circuit for individually controlling the operation of the first, second, third and fourth transistors by respective first, second, third and fourth control signals.

Abstract: Power regulator circuitry is provided for powering loads such as programmable memory element arrays on integrated circuits. The power regulator circuitry may have control circuitry that generates a first digital control signal to turn on and off a regulated power supply circuit and a second digital control signal to turn on and off a switch-based power supply circuit. The outputs of the regulated power supply circuit and switch-based power supply circuit may be connected to an output terminal for the power regulator circuitry. The first and second digital control signals may be used to ensure that the regulated power supply circuit is turned on before the switch-based power supply circuit is turned off. The switch-based power supply circuitry may contain serially connected transistors. The transistors may be turned off in an order that prevents latchup.

Abstract: A DC-DC converter includes a chip including an error amplifier and a pulse width modulator (PWM) having an input connected to an output of the error amplifier, and an inductor driven by said PWM in series with an output node (VOUT) of the converter, wherein a load current flows through the inductor. VOUT is fed back through a network including a feedback resistor (RFB) to an inverting input of the error amplifier. A circuit for sensing the load current includes a first operational amplifier, a sense resistor on the chip having resistance RSENSE coupled to an inverting input of the first amplifier; wherein a sense current related to the load current flows through the sense resistor, a dependent current source provides an output current to supply the sense current. A reference resistor is disposed on the chip having a resistance RREFERENCE which is a fixed multiple of RSENSE. A set resistor is provided having a resistance RSET.

Abstract: A method for regulating a voltage using a linear voltage regulator is provided. The linear voltage regulator has a first circuit with a primary output node and a second circuit having first and second inverters electrically coupled to the primary output node. The method includes receiving a first voltage from a voltage source at the first circuit. The method further includes removing frequency components of the first voltage in a first frequency range to obtain an output voltage at the primary output node utilizing the first circuit. The method further includes removing frequency components of the output voltage in a second frequency range utilizing the first and second inverters of the second circuit, the second frequency range being greater than the first frequency range.

Abstract: A DC-DC converter includes independent first and second outputs to drive respective first and second loads from a common boost module. In one embodiment, a first linear regulator controls a first controlling device for the first output and a second linear regulator controls a second controlling device for the second output. The load requiring the higher voltage controls the boost module.

Abstract: A linear voltage regulator is provided. The linear voltage regulator includes a first circuit configured to receive the first voltage from a voltage source and to remove frequency components of the first voltage in a first frequency range to obtain an output voltage at a primary output node. The linear voltage regulator further includes a second circuit having first and second inverters electrically coupled to the primary output node of the first circuit. The second circuit is configured to receive the output voltage and to remove frequency components of the output voltage in a second frequency range. The second frequency range is greater than the first frequency range.

Abstract: An output compensator for a regulator is provided that can improve the dynamic response of a regulator, and which does not require the redesigning of the power conversion stage or control stage of the regulator, but simple circuit connection of the compensator circuit to the output stage of the regulator. The compensator senses an output signal at a passive component at an output of the regulator; generates a compensating signal based on a difference signal, the difference being a difference between a level of a reference signal for the regulator and the sensed output signal; and applies the compensating signal to the passive output component to reduce the difference between the level of the reference signal and the sensed output signal. The passive output component may be, for example, a capacitor or an inductor, depending on the operation of the regulator.

Abstract: One embodiment of the invention includes an on-chip current-sense system for measuring a magnitude of an output current through a power transistor. The system includes a first sense transistor that conducts a first reference current to or from a phase node and a second sense transistor configured to conduct a second reference current to or from a power rail. The first and second sense transistors can be substantially identical and can be proportionally matched to the power transistor. An OTA receives the first and second reference currents and a third reference current that flows to or from the phase node and generates a sense current that is proportional to the output current in response to the first, second, and third reference currents. A sense circuit compares the sense current with a predetermined magnitude and generates an over-current signal in response to the sense current being greater than the predetermined magnitude to indicate an over-current condition of the output current.

Abstract: A control circuit is provided in which two power sources can be efficiently switched, for a power supply apparatus provided with a step down switching regulator and a linear regulator. A PWM controller generates a pulse width modulation signal with which a duty ratio is controlled so that output voltage of the switching regulator approaches a predetermined reference voltage. A compulsory OFF circuit monitors a switching voltage, and when a first threshold voltage is exceeded, switches a synchronous rectifier transistor OFF. A minimum ON time setting circuit limits the duty ratio of the pulse width modulation signal, so that ON time of the switching transistor is longer than a predetermined minimum value. A selector circuit monitors an error voltage, and when a predetermined state continues for a predetermined first period, puts the linear regulator in an operating state, and the step down switching regulator in a halt state.

Abstract: According to one or more aspects of DC-to-DC voltage conversion as taught herein, a DC-to-DC converter selectively operates in a first mode wherein an included linear pass output circuit supplies the output power from the DC-to-DC converter, in a second mode wherein an included charge pump output circuit supplies the output power, and in a third mode wherein the linear pass and charge pump output circuits operate in parallel to supply the output power. With this third mode, also referred to as a “dual” mode, wherein the linear pass and charge pump output circuits operate in parallel, the DC-to-DC converter keeps the more efficient output circuit on after it has begun switching to operation with the less efficient output circuit. Such switchover may be performed dynamically in response to changing operating conditions. Detected operating conditions may include input voltages, output voltages, and output load conditions.

Abstract: The invention relates to a voltage regulator for operation of a semiconductor memory device. In embodiments, the voltage regulator includes a standby regulator unit and an active regulating unit. Embodiments of the invention decouple the operation of the standby regulating unit and the active regulating unit of a voltage regulator so that both can operate simultaneously, for example during a read operation. In embodiments of the invention, the standby regulating unit includes a short pulse generator and a feedback loop to disable the standby regulating unit for a predetermined amount of time.

Abstract: The step-down converter includes: a switch; an inductor; a rectifier; a smoothing unit; and a current bypass circuit, wherein when the current flowing toward the inductor exceeds a predetermined value, the current bypass circuit forms a path through which the current flows from the input terminal to the output terminal while bypassing the inductor.

Abstract: A method of performing loadflow calculations for controlling voltages and power flow in a power network by reading on-line data of given/specified/scheduled/set network variables/parameters and using control means, so that no component of the power network is overloaded as well as there is no over/under voltage at any nodes in the network following a small or large disturbances.

Abstract: As for a transistor, overlapped are factors such as a variation of a gate insulation film which occurs due to a difference of a manufacturing process and a substrate used and a variation of a crystalline state in a channel forming region and thereby, there occurs a variation of a threshold voltage and mobility of a transistor. This invention provides an electric circuit which used a rectification type device in which an electric current is generated only in a single direction, when an electric potential difference was applied to electrodes at both ends of the device. Then, the invention provides an electric circuit which utilized a fact that, when a signal voltage is inputted to one terminal of the rectification type device, an electric potential of the other terminal becomes an electric potential offset only by the threshold voltage of the rectification type device.

Abstract: A voltage regulator device and accompanying methods are provided for providing efficient voltage regulation to an electronic device. Efficient regulator 400 receives an input voltage on VIN from a battery or some other power supply at node VIN and supplies a stable regulated voltage to load device 404 at node VOUT. Load device 404 pulls different amounts of current and requires different degrees of tolerance on the voltage at VOUT depending upon its operating conditions. Data collection and control circuit 401 is capable of enabling and disabling regulator 402 and regulator 403. Data collection and control circuit 401 is also capable of measuring certain performance parameters associated with load device 404 and the operating conditions of load device 404. Data collection and control circuit 401 enables regulator 402 if said operating conditions are such that when data collection and control circuit 401 enables regulator 403 the performance parameters associated with load 404 are below a predefined standard.

Abstract: An apparatus comprises a circuit having a power supply node and a linear regulator configured to provide a regulated voltage at the power supply node of the circuit. The apparatus further comprises a switching regulator configured to provide input power to the linear regulator from a power source such as a battery. In some implementations, the circuit is a transceiver circuit.

Abstract: A power supply unit comprises a series regulator and a switching DC-DC converter controlled by a PWM signal and connected in parallel with the series regulator, which are switchably enabled by a mode instruction signal depending on the magnitude of a load current. In switching the series regulator and the DC-DC converter, they are simultaneously enabled for a predetermined overlapping time. Further, in changing the operating condition of the DC-DC converter, the width of the PWM signal is shortened to extend the dead time of the DC-DC converter by a predetermined period, thereby suppressing free oscillations and accompanying overshoots that could take place in the power supply unit during switching.

Abstract: An integrated semiconductor component includes a functional circuit and a power control circuit configured to generate a supply voltage from an input voltage. The power control circuit may include a snitching controller and a control circuit configured to set a frequency spectrum of tile Supply voltage and coupled to the switching controller. The control circuit may be configured to determine a current operating state out of at least two possible operating states of the integrated semiconductor component and to set the frequency spectrum dependent from the current operating state.

Abstract: A voltage controller may include a pulse generator and an internal voltage control circuit coupled to the pulse generator. The pulse generator may be configured to generate a control signal in response to at least one of a mode signal and/or an external voltage. The internal voltage control circuit may be configured to generate an internal voltage at an internal voltage node, and the internal voltage control circuit may include a voltage divider, first and second comparators, and a driver. The voltage divider may be coupled between the internal voltage node and a first reference voltage, and the voltage divider may generate a feedback voltage that is between the internal voltage and the first reference voltage.

Abstract: A multi-phase power system including a plurality of Pulse Width Modulation (PWM) controllers is provided, including a first PWM controller and at least one second PWM controller. The first PWM controller is configured to generate at least one first output signal based on a first clock signal, and to insert at least one synchronizing pulse into the first clock signal, the synchronizing pulse having a predetermined characteristic differing from pulses of the first clock signal, and to provide the first clock signal including the synchronizing pulse to the second PWM controller. The second PWM controller is configured to generate at least one second output signal based on the first clock signal, and to synchronize the generation of the first and second output signals using the synchronizing pulse within the first clock signal, thereby maintaining a predetermined phase relationship between the first and second output signals.

Abstract: Disclosed is a voltage generating circuit which steps down a voltage to output a stepped down voltage. The voltage generating circuit includes first and second transistors. The drains of the first and second transistors are connected to a higher voltage power supply. The gate of the first transistor is connected to the gate of the second transistor. The voltage of the gate of the first transistor is controlled by a control circuit such that a voltage of the source of the first transistor can reach a predetermined voltage. A stepped down voltage is outputted from the source of the second transistor.

Abstract: The invention relates to smoothing a consumer electrical circuit supplied by a controllable current sink connected in parallel to the consumer. For this purpose, measuring voltage proportional to a load current supplied to the consumer is derived therefrom. A pick value measuring device makes it possible to determine a maximum value thereof. The difference between the maximum value and measuring voltage makes it possible to control the voltage-controlled current sink in such a way that the sum of a compensation current supplied by the current sink and the load current which runs by the consumer is substantially constant.

Abstract: A digital multilevel memory system includes a charge pump and a voltage regulator for generating regulated high voltages for various memory operations. The charge pump may include a plurality of boost circuits to boost the output of the charge pump during a fast start up. Afterwards, the boost circuits are disabled to allow the charge pump to generate high voltages without boosting. The boost circuits may be successively enabled to boost the voltage. The boost circuits may be loadless. The voltage regulator may operate in an open loop and may include a resistive divider as a reference voltage for regulating the high voltage from the charge pump. The charge pump may include spread spectrum pump clocking to reduce electromagnetic inference for capacitor or inductor on-chip charge pumping.

Abstract: A voltage regulator includes an undervoltage detector having a charge transistor smaller than an output transistor of the voltage regulator, providing a detection path for fast response, compensating undervoltage without large control current when loading changes from light to heavy.

Abstract: A multi-phase power converter and a method for balancing a plurality of currents in the multi-phase power converter. The multi-phase power converter has a pulse width modulation circuit, a current ordering circuit, and a plurality of currents, wherein each current of the plurality of currents has an associated phase. The converter determines the phase associated with one or more currents of a plurality of currents and whether a phase associated with one or more currents of the plurality of currents is active. The current levels of the plurality of currents are determined and a phase associated with a current having one of a lowest current level or a highest current level is activated.

Abstract: Current supply circuit for supplying a circuit with an internal supply voltage on the basis of an external supply voltage with an bipolar transistor for realizing reverse-connect protection for the circuit to be supplied, a supply current flowing through the bipolar transistor's collector-emitter path, a regulating circuit connected to the bipolar transistor ensuring that the bipolar transistor is operated at the limit to saturation.

Abstract: A direct current (DC) remote power controller for remotely controlling DC power between a DC power source and a DC load, comprises: a current sensor for sensing the level of current that the power source supplies to the load and generating a current feedback signal representative of the sensed current level; a current limit controller that compares the current feedback signal to a reference current level and generates a current regulation signal representative of the value of sensed current level above the reference current level; a current limiting device that is responsive to the current regulation signal to limit load current to the reference current level up to a first predetermined level of potential difference across the current limiting device; a load resistance; and a switched-mode DC-to-DC converter in parallel with the current limiting device that senses potential difference across the current limiting device and diverts a portion of the load current from the current limiting device through the load

Abstract: A LDO and a switching regulator are connected in parallel with each other. The power supply device selects and actuates either of the LDO or the switching regulator in accordance with a switching signal from the outside. When making the switch from the LDO to the switching regulator so as to be actuated, the power supply device causes operation periods of the LDO and the switching regulator to overlap each other. At least during the period in which the operation periods overlap each other, the power supply device makes current drive performance of a synchronous rectification transistor of the switching regulator lower and makes the same return to a normal state after the LDO stops its operation.

Abstract: For an internal circuit having a first operation mode consuming a first operational current and a second operation mode consuming a second operational current, which is smaller than the first operational current, a first power source regulator for stepping down a predefined output power supply voltage from an input power supply voltage and having a current supply ability corresponding to the first operational current of the internal circuit and a second power source gulator having a current supply ability corresponding to the second operational current are combined in order to, under the control of a power supply control unit, operate the first step-down type regulator in response to a first control signal instructing the first operation mode in the internal circuit and to operate the second step-down type regulator in response to a second control signal instructing the second operation mode.