Abstract: A constant-voltage power circuit incorporating an over-current protection circuit having a fold back current limiting capability operative through low input voltages, and being capable of arbitrarily setting current outputs. The constant-voltage power supply circuit is configured so that a voltage output with small amplitude from a differential amplifier circuit is subjected to amplitude expansion to be amplified to range fully from the ground potential approximately to the input voltage by means of an amplitude expansion circuit, which includes an inverter consisting of an NMOS transistor and a resistor, and that the voltage resulting from the amplitude expansion is subsequently input to the gate of a PMOS transistor configured to directly control an output transistor.

Abstract: A real current sense apparatus for a DC-to-DC converter uses a current mirror composed by two JFETs to mirror the output current of the converter to generate a temperature-independent mirror current to further generate a current sense signal. Due to the temperature-independence of the mirror current, the current sense signal is also temperature-independent.

Abstract: A differential amplifier having a positive input terminal, a negative input terminal, an output terminal, a bias terminal and a ground terminal is provided. The differential amplifier comprises a differential pair circuit and a current mirror circuit. Wherein, the differential pair circuit is coupled to the positive input terminal, the negative input terminal, the output terminal, and the bias terminal of the differential amplifier. The current mirror circuit receives a constant current from a current source, and mirrors the constant current to the differential pair circuit. The current mirror circuit further connects to the ground terminal of the differential amplifier, and the terminal of the current mirror circuit receiving the constant current is coupled to a first source/drain terminal of a first PMOS transistor. A second source/drain and a gate of the first PMOS transistor are connected to the bias terminal and the output terminal of the differential amplifier, respectively.

Abstract: According to one embodiment, a computer system is disclosed. The computer system includes an integrated circuits (IC), a power supply that supplies power to the IC and an over-current protection (OCP) circuit. The OCP circuit prevents the exceeding a predetermined power threshold during a short circuit condition while the IC is enabled to receive a greater power level.

Abstract: A band-gap type constant voltage generating circuit is produced in a semiconductor chip, and has a first potential terminal and a second potential terminal. A band-gap circuit includes first and second transistors having respective bases connected to each other, a first resistor connected between emitters of the first and second transistors, and a second resistor connected between the emitter of the second transistor and the first potential terminal. A constant voltage production circuit is provided between the first and second potential terminals to produce and output a constant voltage based on a base-emitter voltage of the second transistor of the band-gap circuit, and the constant voltage is fed as a feedback signal to the base of the second transistor of the band-gap circuit. A driver circuit is provided between the first and second potential terminals and connected to collectors of the first and second transistors to drive the band-gap circuit.

Abstract: A DC to DC power converter includes synchronous rectifiers which respond to a control waveform. Negative current from a load into the power converter is prevented by increasing the converter output voltage at a minimum current limit. The synchronous rectifiers may be held off in response to decision logic by activation of a hold-off circuit connected to a control terminal of a synchronous rectifier or of an ORing transistor at the converter output. When the synchronous rectifier is subsequently enabled, its control waveform may be increased slowly relative to the switching cycle.

Abstract: A current reference circuit has a band gap voltage generating circuit, a voltage buffer, a voltage-to-current converting circuit and an auto-tuner. The band gap voltage generating circuit generates a band gap reference voltage. The voltage buffer generates a first bias voltage and a second bias voltage. The voltage-to-current converting circuit generates a source current in response to a tuning voltage. The auto-tuner generates the tuning voltage to maintain a transconductance. Thus, the current reference circuit may automatically adjust the transconductance, so that the current reference circuit may supply the source current that is stable against temperature and process variations.

Abstract: A series regulator for outputting a regulated voltage and a booster circuit of a charge pump type for outputting an output voltage by boosting the regulated voltage are connected in series. The series regulator is controlled so that the output voltage is maintained constant. A main circuit current of the series regulator is subject to current limitation. An excess signal commensurate of an excess of a current indicator value over a current reference value is generated. A voltage control signal is reduced in level in accordance with the excess signal.

Abstract: A DC—DC CMOS converter including when the supply voltage is low, the current limit is automatically reduced to the maximum possible value that maintains the comparator operative, rather than simply switching off the converter.

Abstract: An apparatus has a green compact electrode including a material of a coating formed on a workpiece by a discharge, a power source for supplying a first voltage, a voltage detector for detecting a voltage between the workpiece and the electrode, and a pulse current generator for generating and outputting a pulse current from the first voltage, and for cutting off the output when a predetermined period of time has passed after the voltage is detected to be less than a detection voltage. The pulse current is supplied between the workpiece and the electrode, and the detection voltage is less than the first voltage by 5% to 20% of the first voltage.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: An inventive switching type dc-dc converter is adapted to set a protective reference current level lower for a decreased output voltage, and stop the switching control signal supplied to a switching transistor circuit when the detected current level exceeds the protective reference current level. In addition, in case where the output voltage declines due to, for example, a circuit failure such as short-circuiting, the switching period of the switching transistor circuit is extended. Thus, the switching type dc-dc converter is provided with a fold-back current limiting type protection characteristic through reduction of the protective reference current level and extension of the switching period of cycle.

Abstract: A power switching circuit comprising a first power switching device the first power switching device having a control electrode and two main current carrying electrodes, a sense circuit for providing a signal proportional to the current through the first power switching device and an active clamp circuit connected to said control electrode of said first power switching device, wherein said active clamp circuit provides a variable clamp voltage between one of the main electrodes of the first power switching device and the control electrode when the current in the first power switching device exceeds a threshold level the variable clamp voltage being related to current through the first power switching device.

Abstract: A constant voltage supply unit having a high-speed load response, equipped with a fold-back type over-current protection function in which an output current detection voltage indicative of the output current is compared with the sum of a feedback voltage indicative of the output voltage and an offset voltage. The over-current protection function has a characteristic that the offset voltage is inversely proportional to the output-current detection voltage, so that the offset voltage is large when the output-current detection voltage (or the output current) is low, and decreases with the output-current detection voltage. In addition, the constant-voltage power supply unit allows enhance feedback of ac components in the feedback loop so as to enhance the ESR of the load-side capacitor, thereby securing phase compensation to prevent oscillations in the feedback loop.

Abstract: An integrated Low Dropout (LDO) linear voltage regulator provides improved current limiting. A differential voltage amplifier compares an output voltage to reference voltage and controls a pass transistor to make the output voltage substantially match the reference voltage. This is accomplished by sensing the output voltage of the voltage regulator for application to a first input of the differential amplifier and coupling a second input of the differential amplifier to the reference voltage. A current sense transistor utilizes current mirroring techniques to sense the current passing through the pass transistor to the output. This sensed current is compared to a reference current. The result of that comparison is fed back to the differential voltage amplifier to in a manner that increases the apparently sensed output voltage in situations where the sensed current exceeds the reference current.

Abstract: A low drop out voltage regulator (10) that receives an input voltage and generates a substantially constant output voltage includes a gain stage (12), a buffer stage (14), an output driver transistor (16), and first and second load current sense circuits (18, 20). The first load current sense circuit is connected between the output driver transistor and the buffer stage and adaptively increases a bias current of the buffer stage as a function of the load current. The second load current sense circuit is connected between the output driver transistor and the gain stage and adaptively decreases a bias current of the gain stage as the load current increases.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: In a stabilized power supply unit having a current limiting function, the unit is designed to have a steep over-current dropping characteristic. This minimizes the over-current region, prevents oscillation during a startup, and limits inrush current during a start up within a predetermined range. The output voltage of the power supply unit provides a constant output voltage by controlling an output transistor by means of a differential amplifier amplifying the difference between a reference voltage and an output feedback voltage. The power supply unit has a first high-gain, slow-response type current limiting circuit that outputs a first current limiting signal when the output current of the power supply unit exceeds a predetermined level, and a second low-gain, quick-response type current limiting circuit that outputs a second current limiting signal when the outputs exceeds the predetermined level.

Abstract: A two-wire sensor (6) is attached to one pole of a voltage distribution source (U) by an initial connecting line (V1) in which a current-limiting resistor (R1) is positioned and is attached to the other pole by a second connecting line (V2). Parallel to the series connection consisting of the two-wire sensor (S) and the current-limiting resistor (R1) is at least one limiting diode (D1). A current regulator (SR) which is attached to the poles of the power source (U) regulates a parallel current (I) which runs parallel to the current through the two-wire sensor (D), so that there is a sum current at the poles of the power source (U) that always corresponds to the measured value delivered by the two-wire sensor (S). The regulating inputs of the current regulator (SR) are connected to the terminals of a current-sensing resistor (R2) positioned in a connecting line (V1). When a HART®-interface is used with the two-wire sensor (S) a HART®-resistor (RH) is positioned in one of the two connecting lines (V1).

Abstract: A DC-to-DC converter includes one or more power switches, a pulse width modulation circuit for generating control pulses for the power switches, and an output inductor connected to the power switches. A thermally compensated current sensor is connected to an intrinsic current sensing element exhibiting a temperature-based parameter non-linearity. The thermally compensated current sensor has a temperature coefficient that substantially matches a temperature coefficient of an intrinsic power converter element used to measure current flow, thus linearizing the current measurement. Also, a current feedback loop circuit cooperates with the pulse width modulation circuit to control the power switches responsive to the thermally compensated current sensor.

Abstract: A voltage regulator circuit includes an output stage circuit which operates either in a normal operation state in which a regulator output voltage stabilized in accordance with an input control voltage is supplied from a regulator output terminal to an external load circuit or in an overcurrent protection state in which a regulator output current supplied from the regulator output terminal to the external load circuit is limited up to a predetermined level. The voltage regulator circuit further includes a first control circuit which generates the control voltage in accordance with the regulator output voltage and outputs the control voltage to the output stage circuit, and a second control circuit which monitors a state of the output stage circuit and switches the output stage circuit between the normal operation state and the overcurrent protection state in accordance with the monitored state of the output stage circuit.

Abstract: An apparatus and method provide for temperature calibrating an over-current limit in a linear regulator. Output current is delivered to the load through a power pass device that is responsive to a gate control signal. A transistor circuit provides a sense current that is proportional to the output current. A diode device senses the operating temperature of the linear regulator. An analog-to-digital converter converts the sensed operating temperature to a digital quantity. A resistance value associated with a resistance circuit is changed in response to the digital quantity. The resistance circuit converts the sense current to a voltage that is compared to a reference voltage. An amplifier is arranged to adjust the gate control signal when the reference voltage is exceeded such that the over-current condition is detected.

Abstract: A power supply includes a storage capacitor which can be charged with a rectified input current by means of a current-limiting element which is controlled by a drive circuit. The direct-axis component of current and the direct-axis component of voltage on the current limiting element are supplied to the control circuit as input values and the current limiting element is controlled in such a way that it is not subjected to more than a predetermined maximum power loss.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: A DC-to-DC converter includes one or more power switches, a pulse width modulation circuit for generating control pulses for the power switches, and an output inductor connected to the power switches. A thermally compensated current sensor is connected to an intrinsic current sensing element exhibiting a temperature-based parameter non-linearity. The thermally compensated current sensor has a temperature coefficient that substantially matches a temperature coefficient of an intrinsic power converter element used to measure current flow, thus linearizing the current measurement. Also, a current feedback loop circuit cooperates with the pulse width modulation circuit to control the power switches responsive to the thermally compensated current sensor.

Abstract: A power supply device which converts a voltage by a switching method is connected to a load. Whether a current supplied from the power supply device to the load falls within a proper range is determined. At this time, while preventing an increase in cost in current detection and reducing Joule loss caused by an unwanted resistance component, it is determined that the current falls within the proper range. In order to determine a current supplied from a DC/DC converter to the load, a current determination unit (1) is arranged. The current determination unit (1) compares, with a preset voltage, a voltage obtained by DC-detecting a gate driving pulse signal used to turn on/off a switching MOS transistor (3), thereby determining whether the current flowing from the DC/DC converter to the load exceeds a predetermined current (proper range). In current detection, Joule loss by an unwanted resistance component can be reduced.

Abstract: According to some embodiments, a control signal is generated to reduce resonance of a circuit at an operation point, a characteristic of the control signal based on a proximity of an existing operation point to the operation point. Generation of the control signal may include sensing of a current associated with an input voltage signal, generation of a current-based signal based on the sensed current, and generation of the control signal based on a phase difference between the current-based signal and the input voltage signal.

Abstract: A DC-to-DC converter includes one or more power switches, a pulse width modulation circuit for generating control pulses for the power switches, and an output inductor connected to the power switches. A thermally compensated current sensor is connected to an intrinsic current sensing element exhibiting a temperature-based parameter non-linearity. The thermally compensated current sensor has a temperature coefficient that substantially matches a temperature coefficient of an intrinsic power converter element used to measure current flow, thus linearizing the current measurement. Also, a current feedback loop circuit cooperates with the pulse width modulation circuit to control the power switches responsive to the thermally compensated current sensor.

Abstract: A DC-to-DC converter includes one or more power switches, a pulse width modulation circuit for generating control pulses for the power switches, and an output inductor connected to the power switches. A thermally compensated current sensor is connected to an intrinsic current sensing element exhibiting a temperature-based parameter non-linearity. The thermally compensated current sensor has a temperature coefficient that substantially matches a temperature coefficient of an intrinsic power converter element used to measure current flow, thus linearizing the current measurement. Also, a current feedback loop circuit cooperates with the pulse width modulation circuit to control the power switches responsive to the thermally compensated current sensor.

Abstract: A voltage down converter 10 for providing a supply voltage and current to a device, such as a semiconductor device. The voltage down converter includes a first circuit 12 that supplies steady state or “DC” current to the device, and a second circuit 14 that supplies the fluctuating or “AC” current to the device. The first circuit 12 includes a first comparator 18 that drives a first transistor P1 to supply most of the steady state current. The second circuit 14 includes a second comparator 20, which is larger than the first comparator 18, and which drives a second transistor P2, which is smaller than the first transistor P1, to supply the fluctuating current to the device. The converter 10 further includes a feedback circuit 16 for controlling the supply voltage.

Abstract: In a conventional stabilized direct-current power supply device with a soft starting function, soft starting is achieved by exploiting the rise in a reference voltage. Thus, soft starting is impossible when the reference voltage has already risen. A stabilized direct-current power supply device of the invention has a current suppression circuit that, when the output voltage rises, suppresses the current output from a voltage conversion circuit that converts the input voltage into the output voltage to be fed out. Thus, soft starting is possible even when the reference voltage has already risen.

Abstract: A DC-to-DC converter includes one or more power switches, a pulse width modulation circuit for generating control pulses for the power switches, and an output inductor connected to the power switches. A thermally compensated current sensor is connected to an intrinsic current sensing element exhibiting a temperature-based parameter non-linearity. The thermally compensated current sensor has a temperature coefficient that substantially matches a temperature coefficient of an intrinsic power converter element used to measure current flow, thus linearizing the current measurement. Also, a current feedback loop circuit cooperates with the pulse width modulation circuit to control the power switches responsive to the thermally compensated current sensor.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: A stabilized power supply-use device of the present invention, which is mounted on a switching power supply, is an IC into which power transistors, a control circuit for controlling a base current of the power transistors, and other electronic components are formed, and an overcurrent detecting resistor connected in series with the power transistor is realized by a resister provided externally to the IC. Therefore, as compared to the overcurrent detecting resistor being made up of aluminum wiring patterns inside the IC, the overcurrent detecting resistor of the present invention dramatically decreases variations in value of resistance, whereby it is possible to improve an accuracy of voltage detection and to arbitrarily set a value of resistance. This eliminates the need for a needlessly increased input power capacity in a test based on safety standard and other tests, thereby enabling a switching power supply manufactured at a lower cost.

Abstract: A device is disclosed to determine when a resistive load is connected to a source of alternating current (“AC”) power. The device includes a signal path and an AC power path. The device also includes a processor connected to a sensing circuit for determining a current level in the AC power path. The processor indicates an off condition according to the current level. The device also includes a power switch for turning off the AC power when instructed by the processor during the off condition.

Abstract: Method and system for providing current transient control for N electrical devices, numbered (N≧2), where each device has an associated current transient I(n) upon power-up or power-down. Q subsets (preferably mutually exclusive) of devices are provided, where the sum of current transients (in-rush, etc.) for all devices in subset number q (q=1, . . . , Q; Q≧2) is no greater than a selected current value, such as (i) a maximum current that can be supplied by a current source or the maximum current that can be passed through a front end component associated with at least one device without injuring the device and (ii) a maximum current that can be supplied by a current source for power-up. A device may be redundantly assigned to more than one subset, to improve reliability. A time delay is implemented between power-up (or powerown) of any two distinct device subsets. Within an activated subset, a time delay is optionally implemented between any two distinct devices in the subset.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: In a power supply apparatus for discharge surface treatment which uses a green compact electrode as a discharge electrode, allows a pulse-type discharge to take place between said discharge electrode and a workpiece, and forms a film, which is made of an electrode material or a material obtained when the electrode material reacts to a discharge energy, on a surface of the workpiece following three measures are taken. (1) When a discharge voltage detected by the voltage detection means is less than or equal to discharge detection voltage set value which is slightly lower than a power supply voltage, the electric current cut-off means forcibly cuts off an output of the oscillator so that long-time pulse is prevented. (2) A capacitor is connected in parallel with an oscillation circuit of the oscillator, and the long-time pulse is prevented by capacitor discharge. (3) Time that the discharge takes place once is controlled by a timer so that the long-time pulse is prevented.

Abstract: In a stabilized power supply unit having a current limiting function, the unit is designed to have a steep over-current dropping characteristic. This minimizes the over-current region, prevents oscillation during a startup, and limits inrush current during a start up within a predetermined range. The output voltage of the power supply unit provides a constant output voltage by controlling an output transistor by means of a differential amplifier amplifying the difference between a reference voltage and an output feedback voltage. The power supply unit has a first high-gain, slow-response type current limiting circuit that outputs a first current limiting signal when the output current of the power supply unit exceeds a predetermined level, and a second low-gain, quick-response type current limiting circuit that outputs a second current limiting signal when the outputs exceeds the predetermined level.

Abstract: A stabilized power supply unit having a current limiting function, comprising a detection transistor impressed with the same control voltage as the output transistor of the power supply unit, adapted to output a detection current which is exactly proportional to the output current, irrespective of the magnitude of the output current. The current detection transistor is controlled by the control voltage controlling the output transistor. A voltage correction unit is provided to control the voltage of the output end of the current detection transistor, equalizing the voltage with the output voltage. This arrangement provides a detection current exactly proportional to the output current.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: A voltage regulator (15) utilizes a first current source (31) and a second current source (32) to form a reference current to limit current flow through an output transistor (13) during a start-up period. After the start-up period expires, the first current source (31) is disabled and the voltage regulator (15) controls the output voltage produced by the output transistor (13) instead of controlling the current flow through the output transistor (13).

Abstract: A power regulator regulates the power provided to a transistor-based circuit, such as that which might be employed in a high stability MTI radar system. According to the invention, a variable reference voltage is controlled based on the frequency of operation. The output voltage of the power regulator is then modified accordingly. Preferably, the reference voltage is controlled based on the location of the target frequency in relation to the overall operational frequency band, which has been divided into a series of sub-bands.

Abstract: A low dropout voltage (LDO) regulator having an adaptive zero frequency circuit is described. The adaptive zero frequency circuit maintains the stability of the LDO regulator and improves the transient response of the LDO regulator under a range of values for the output current, whereas the output current inversely varies with the load resistance coupled to the output of the LDO regulator. The adaptive zero frequency circuit generates a zero having a frequency which varies with the output current. Hence, the frequency of the zero changes to maintain the stability of the LDO regulator despite the variation in the frequency of the low-frequency pole generated by the load resistance and the load capacitance (or output capacitor) coupled to the output of the LDO regulator.

Abstract: A voltage regulator includes a power transistor for providing an electrical current to a load circuit connected to an output of the regulator. The delivered current is limited by a limitation circuit within the regulator. A stabilization resistor is connected between the power transistor and the output of the regulator. The limitation circuit includes a fixed-voltage generator, and a comparator for comparing the voltage generated in the stabilization resistor by the output current of the regulator with the fixed voltage. The output of the comparator controls an adjustment transistor that limits the current delivered by the power transistor.

Abstract: A voltage regulator circuit that provides the current necessary to drive an output driver during transients and maintain low output impedance, while having a much better dropout voltage than a single source follower gain stage includes: an output driver 22; a source follower 34 for controlling the output driver; a localized feedback gain loop coupled to the source follower 34; and an amplifier 24 for controlling the source follower 34.

Abstract: A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise.

Abstract: The present invention is a power monitoring circuit for sensing line conditions in a three phase power line. In the circuit a plurality of series connected power supplies for powering various components of the circuit are connected in series with a current sensing element for sensing current supplied to the power supplies. The power supply and current sensing element arrangement, in turn, is connected across a three phase bridge rectifier, which is in communication with the three phase power supply line. A circuit analyzer in communication with the current sensing element senses unbalanced line conditions based at least in part on a signal developed by the current sensing element. Preferably, the circuit further includes a three voltage reducing resistors interposed between the three phase power line and the bridge rectifier for reducing the voltage stresses encountered by the circuit's components.

Abstract: A feedback apparatus and method for adaptively controlling power supplied to a hot-pluggable subsystem controls the inrush current of the hot-pluggable subsystem upon application of power. The apparatus and method adaptively control a pass device by detecting the current through the pass device during initial charging of a load capacitance and scaling back the turn-on rate at the pass device control terminal input in conformity with the detected current and a predetermined rate set by a ramp generator. A ramp capacitor is coupled to the control terminal of the pass device through a diode to permit use of the capacitor for timing purposes as well as preventing transient turn-on of the pass device during initial application of power.

Abstract: A circuit for limitation of maximum current delivered by a power transistor comprises: a network for detection of the current delivered by the power transistor which generates a first electrical signal; a reference network for generating a reference current proportional to a resistor and self-limited, provided by means of a current generator circuit and a limiting circuit with current mirror; and an operational amplifier which compares the first electrical signal with the reference current and which tends to inhibit the power transistor if the current delivered exceeds a certain threshold value.