Abstract: Included are a Zener diode D2 having a cathode connected onto a voltage output line, dividing resistors having one terminal connected to the anode of the Zener diode D2 and having the other terminal grounded, a transistor Q1 having a base connected to the junction point between the dividing resistors via a resistor and having an emitter grounded, a transistor Q2 having a base connected to the junction point between the dividing resistors and having an emitter grounded, and a microcomputer having an undervoltage detection terminal 10a which is connected to the collector of the transistor Q1 and to which 3.3 V is externally applied and a power supply terminal 10b which is connected to the collector of the transistor Q2 and via which a P-ON-H signal of 3.3 V that starts a power supply circuit 126 when the power supply is turned on is transmitted.

Abstract: Systems, circuits, and methods are described for providing efficient, monitoring capabilities for providing output reactive to monitored conditions. According to the disclosed methods, steps are included for providing a floating gate monitoring circuit in association with a monitored circuit and programming the floating gate to a selected charge level. The programmed floating gate charge level is then compared with a signal level in a monitored circuit. In an additional step, selected comparison criteria are used for selectably activating output. Exemplary embodiments of methods and associated circuits and systems employing the methods are also disclosed, in which protection for a monitored circuit is provided in the event of undervoltage, undercurrent, overvoltage, or undervoltage.

Abstract: The on-vehicle electronic control device includes a main power supply circuit fed with power from an on-vehicle battery through an output contact of a power supply relay and a main power supply terminal of a connector to supply a stabilized control voltage to a microprocessor. When contact failure occurs in the main power supply terminal, the main power supply circuit is fed with bypass power from the output contact through a first electrical load and a commutation diode to perform the one of the report of the abnormality and the storage of the abnormality occurrence history information. A bypass power fed state is detected when an input voltage to the main power supply circuit is lower than a power supply voltage of the on-vehicle battery.

Abstract: A driver circuit includes an output, at least one transistor including a load section coupled between the output and a supply voltage, and a circuit coupled to a control terminal of the at least one transistor to apply a control voltage to the control terminal in at least one operation mode of the driver circuit. The control voltage is within a predetermined voltage range de-pending on a first predetermined voltage below a nominal voltage range of the output.

Abstract: A signal source generates a reference voltage, and a voltage regulator receives the reference voltage and generates an output voltage and current. During normal operation, a pass element in the voltage regulator generates the output voltage, and a sense element generates a sense voltage. A first voltage detector detects a short-circuit condition using the sense voltage. A second voltage detector deactivates the pass element in response to the detection of the short-circuit condition. The second voltage detector also detects removal of the short-circuit condition and automatically reactivates the pass element. The first voltage detector may detect the short-circuit condition by detecting a drop in the sense voltage. The second voltage detector may detect the removal of the short-circuit condition by applying a test current to a load. Both the first and second voltage sensors may not consume any direct current power during normal operation of the voltage regulator.

Abstract: Systems and methods for discharging a high-voltage bus coupled to a discharge circuit are provided. A method comprises obtaining a first voltage level of the high-voltage bus. The method further comprises determining a first discharge time based on the first voltage level and activating the discharge circuit. The method further comprises obtaining a second voltage level of the high-voltage bus after the first discharge time, comparing the first voltage level and the second voltage level, and deactivating the discharge circuit if a difference between the first voltage level and the second voltage level is less than a threshold value.

Abstract: A protecting circuit for a battery used to power an electronic system includes a control circuit and a sensing circuit. The sensing circuit includes a tri-axial accelerometer having X, Y and Z axes. The tri-axial accelerometer is capable of detecting position changes of the battery and outputs through the X, Y and Z axes voltages that correspond to the position changes. The sensing circuit ultimately outputs a controlling voltage to the control circuit according to the voltages outputted by the X, Y and Z axes. When the battery is being installed onto or uninstalled from the electronic system, the outputted controlling voltage makes the control circuit OFF and the battery cannot power the electronic system. When the battery have been installed onto the electronic system, the outputted controlling voltage turns the control circuit ON and the battery can supply power to the electronic system.

Abstract: A power status notification method notifying a first device that a second power supply of a second device different from a first power supply of the first device is turned off, where a source voltage of the first power supply is different from a source voltage of the second power supply. The power status notification method and circuit include supplying the first device with a low-level notification signal indicating a power off state of the second power supply in a case where the source voltage of the second power supply drops to a predetermined voltage or is less than the predetermined voltage and setting the predetermined voltage at a value higher than a threshold level at which a circuit of the first device supplied with the notification signal recognizes as a low level.

Abstract: A method for identifying a cause for insufficiency of an output voltage reduced to or below an undervoltage set value comprises a first comparison step for comparing the output voltage to a fixed first undervoltage set value and a second comparison step for comparing the output voltage to a second undervoltage set value that follows up the output voltage with a time lag, wherein the cause for the output voltage insufficiency is identified based on the steps and notified as a warning. As a preferable mode, the first undervoltage set value is set by means of a reverse conducting voltage of a voltage regulating diode D1 and the second undervoltage set value is set by means of a charging voltage of a capacitor C1 for directly or indirectly charging the output voltage.

Abstract: A current-mode under voltage lockout (UVLO) circuit provides an output signal that indicates to connected devices whether a connected power supply is sufficient (i.e., of sufficient strength and stability) based on a comparison of a current that is proportional to the power supply and a reference current. The current-based UVLO circuit employs a reference current generator that is capable of providing a stable reference current and a voltage-to-current converter that provides a current proportional to the power supply voltage. A comparator compares the reference current to the current proportional to the power supply voltage and determines based on the magnitudes of the two currents whether the power supply voltage is sufficient or ‘good’ and generates an output signal indicating the status of the power supply voltage.

Abstract: The present invention is an electrical circuit that disconnects an electrochemical cell from a load when the cell's voltage descends to a predetermined value. The present invention is also applicable to a battery configuration and its corresponding electrochemical cells. The predetermined value is designed to decrease the chance that the cell or battery will become unstable while connected to the load.

Abstract: A power switching circuit according to an exemplary embodiment of the present invention includes an output transistor connected between a power supply terminal VCC and an output terminal OUT, an output controller which controls a conducting state of the output transistor according to an input signal, a sense transistor having a gate commonly connected with the output transistor, which detects an output current flowing into the output transistor, an output current detection terminal in which a detection voltage is generated according to the output current detected by the sense transistor and a short circuit detector which detects a short circuit condition of the output current detection terminal according to the detection voltage and stops the output transistor or limits the output current.

Abstract: Disclosed is a circuit arrangement (10) for recognizing an undervoltage of an energy source (12). Said circuit arrangement (10) comprises a transistor switch (48) and at least one additional switching means (30). The inventive circuit arrangement (10) is characterized in that the transistor switch (48) and the additional switching means (30) have a low resistance in an operational state of the circuit arrangement (10) while the transistor switch (48) blocks the additional switching means (30) in order to interrupt the voltage supply when a supply voltage (U) of the energy source (12) drops below a defined voltage value (US).

Abstract: For protecting a power system, two or three of over current, thermal and under voltage protection circuits are integrated as one protection circuit but operate independently, and one or more protection points thereof are adjusted dynamically in response to detected condition of the power system. Specifically, using voltage and current conditions in the power system to modify the over current protection and the thermal protection maximizes the performance of the power system and covers the process bias in the circuits.

Abstract: For protecting a power system, two or three of over current, thermal and under voltage protection circuits are integrated as one protection circuit but operate independently, and one or more protection points thereof are adjusted dynamically in response to detected condition of the power system. Specifically, using voltage and current conditions in the power system to modify the over current protection and the thermal protection maximizes the performance of the power system and covers the process bias in the circuits.

Abstract: A driving circuit of a switch includes first and second transistors connected in series to each other and to relative intrinsic diodes in antiseries and driven by a driving device that includes at least one first and one second output terminal connected to the switch to supply it with a first control signal for driving the switch in a first working state and a second control signal for driving the switch in a second working state. At least one latch circuit coupled between respective common gate and source terminals of the first and second transistors supplies the common gate terminal with the first and second control signals, respectively, according to the working state to turn off and turn on the first and second transistors.

Abstract: According to one embodiment, a voltage regulator includes a switch configured to selectively conduct electrical energy according to a signal, and circuitry configured to provide the signal to implement a soft start procedure comprising varying frequency and duty cycle of the signal.

Abstract: A system, apparatus and a method are described that provide a voltage clamp for a single-supply system. In particular, a negative voltage clamp prevents a negative over-voltage in a system having only a positive independent voltage source. For example, certain analog-to-digital converters and other circuits allow input signals below the negative supply, or ground in single-supply systems, either by direct sampling or using input attenuation resistors. The negative clamp allows the circuit to provide accurate negative over-voltage protection and the absence of this claim would result in over-voltage protection in positive voltage directions only.

Abstract: A signaling device includes an electrical circuit which discharges an electrical energy storage device through an electrically powered alert mechanism via a biased open transition switch upon disruption of electrical power in an electrical system of a work machine. A work machine is further provided having an alert device coupled with a normally closed electrical power circuit, the alert device being activated upon opening of the normally closed electrical circuit via a transistor switch. An associated method includes using the signaling device to alert a work machine operator to a predetermined condition by closing a normally open electrically switch to connect an electrical energy storage device with an electrically powered alert mechanism, via an electronic controller or via interruption of electrical power in a normally closed electrical circuit of a work machine.

Abstract: Provided is a circuit for detecting power supply voltage drop having a small circuit scale. An NMOS transistor (12) generates a source voltage based on a voltage obtained by subtracting an absolute value of a threshold voltage and an overdrive voltage from a power supply voltage with reference to the power supply voltage. An NMOS transistor (17) is turned on/off based on the source voltage of the NMOS transistor (12). A PMOS transistor (15) generates a source voltage based on a voltage obtained by adding an absolute value of a threshold voltage and an overdrive voltage to a ground voltage with reference to the ground voltage. A PMOS transistor (19) is turned on/off based on the source voltage of the PMOS transistor (15).

Abstract: A switched power rail monitor compares voltages provided by a switched power rail and a power source to detect a predetermined differential indicative of a fault at the switched power rail. A switched power rail fault is communicated to a power manager to take corrective action, such as cutting off power to information handling system components. In one embodiment, a pair of bipolar junction transistors monitor the voltage differential to send an enable signal if the differential is within limits and a disable signal if the differential exceeds limits.

Abstract: A voltage comparison unit compares a battery voltage with a predetermined threshold voltage, and outputs a comparison signal. A sequence circuit receives the comparison signal and a start-up signal instructing start-up of equipment mounted with a UVLO circuit, and executes a predetermined sequence when start-up is instructed by the start-up signal in a state the battery voltage is higher than the threshold voltage. A voltage control unit switches the threshold voltage based on the comparison signal and the start-up signal.

Abstract: A portable device includes a voltage regulator for generating a regulated voltage that is supplied to a processor and to a load by way of a line protection switch, which controls a load current supplied to the load, e.g., in response to a signal supplied by the processor. The line protection switch includes a gate control circuit with a comparator that detects a short circuit in the load by comparing the regulated voltage against a reference voltage. When a short circuit causes the regulated voltage to drop below a predetermined minimum voltage (e.g., 4.5V), the comparator de-asserts the control signal, thereby turning off the switch before the regulated output voltage falls below a minimum operating voltage (e.g., 4.35V) of the processor.

Abstract: There is provided an apparatus for protection against over voltages and/or under voltages. The apparatus includes a pass transistor through which an input voltage is applied, the input voltage varying between a low voltage and a high voltage, and means for selectively varying the gate voltage of the pass transistor when the input voltage is transitioning from the low voltage to the high voltage or from the high voltage to the low voltage. The pass transistor may include an NMOS or a PMOS transistor.

Abstract: An output circuit for a circuit includes an input node coupled to the circuit, an output node, a reference potential terminal, a supply potential terminal, a semiconductor switch connected between the input node and the output node, and a control circuit. The control circuit is designed to open the semiconductor switch when the potential at the output node is higher than a first limit potential depending on a potential applied to the supply potential terminal, or when the potential is lower than a second limit potential depending on a potential applied to the reference potential terminal, and to close the semiconductor switch when the potential is between the first and the second limit potential. Such an output circuit has the advantage that the circuit is protected both against an overvoltage applied to the output node and a polarity inversion, wherein only monolithically integratable semiconductor devices are used.

Abstract: An inductive load is connected between an output node and a first power supply which supplies a first power supply voltage. An inductive load driving apparatus includes a flyback voltage generation control circuit connected in series with the inductive load through the output node between the first power supply voltage and a second power supply voltage which is lower than the first power supply voltage. The flyback voltage generation control circuit includes a switch turned on in response to a first control signal and turned off in response to a second control signal, and a flyback voltage is generated on the output node when the switch is turned off, and is not generated when the switch is turned on.

Abstract: A microcomputer 60 takes in voltages output from the sustaining voltage Vsus generation circuit 52, the addressing voltage Vadd generation circuit 53, and the standby voltage generating circuit 54 via A/D input ports 1 through 6 mounted on the microcomputer board, and performs examinations to judge whether abnormal values are detected about the voltages. If there is at least one abnormal value detected, the main power supply is set OFF and after a predetermined time the main power supply is set ON again to perform a reexamination. If the number of times when abnormal values about a certain voltage are detected reaches the number of abnormal value detections N, the main power supply is left OFF. The number of abnormal value detections N for the Vsamp, the Vset, the Ve or the Vscan, is set larger than the number of abnormal value detections set for the Vsus or the Vadd.

Abstract: An overload detector/enunciator circuit. The overload detector/enunciator circuit detects an overloaded condition of a backup generator and provides a relatively immediate indication of the overload to occupants of the residence or facility receiving power from the backup generator such that correction of the overload condition can be effected before any damage to the generator or load devices can occur.

Abstract: A supply voltage removal detecting circuit, a display device and method for removing a latent image when a supply voltage is disconnected, in which the supply voltage removal detecting circuit includes a voltage controller, a detection signal generator, and an output unit. The voltage controller controls voltages such that when a first supply voltage and a second supply voltage stay at a first level, the voltage at a first node is greater than the voltage at a second node, and when the first supply voltage or the second supply voltage becomes a second level, the voltage at the second node stays at a specific level, and the voltage at the first node is less than the specific level. The detection signal generator generates a detection signal by comparing the voltage at the first node with the voltage at the second node.

Abstract: A system and a method are disclosed for providing a temperature compensated under-voltage-lockout circuit that has a trip point voltage that is not sensitive to temperature variation. The under-voltage-lockout circuit of the invention comprises (1) an inverter circuit that is coupled to a supply voltage and (2) a temperature compensation circuit that is coupled to the supply voltage and to the inverter circuit. The temperature compensation circuit and the inverter circuit temperature compensate a trip point voltage of the inverter circuit by driving an input of the inverter circuit with a voltage that has a same temperature coefficient as the trip point voltage of the inverter circuit.

Abstract: Provided is a DC-DC converter including a short-circuit protection circuit which can stably perform a reset operation and a stop operation. The short-circuit protection circuit includes a detection circuit, a delay circuit, and a latch circuit. The delay circuit is reset in response to an output voltage abnormality signal related to a switching regulator which is outputted from the latch circuit. The latch circuit is reset based on an AND operation between the output voltage abnormality signal and a UVLO signal.

Abstract: An undervoltage detection circuit includes a first transistor and a second transistor coupled to a supply voltage node and arranged to form a current mirror. The undervoltage detection circuit also includes a first bipolar transistor and a second bipolar transistor. A collector of the first bipolar transistor is coupled to the first transistor, and an emitter of the first bipolar transistor is coupled to a reference voltage node. A collector of the second bipolar transistor is coupled to the second transistor and an emitter of the second bipolar transistor is coupled to the reference voltage node through a first resistor. The undervoltage detection circuit further includes a third transistor coupled through a second resistor to an input voltage node. An output signal indicative of an input voltage is derived from a voltage established at the collector of the second bipolar transistor.

Abstract: An exemplary electric outlet includes a power cable having a live wire and a naught wire; a first socket connected to the power cable; and at least one second socket connected to the power cable via an electric switch. The electric switch turn off the at least one second socket when a power of the first socket drops below its threshold value.

Abstract: An objective is to provide a highly-reliable undervoltage lockout circuit which can block and permit normal gate-driver output even when a supply voltage steeply increases. The undervoltage lockout circuit includes a reference-voltage circuit for outputting a reference voltage, a monitor-voltage circuit for outputting a monitor voltage, and a comparator for outputting, the reference voltage and the monitor voltage being inputted thereinto, a high/low signal, according to a comparison result of the reference voltage and the monitor voltage, in which the time constant of the monitor-voltage circuit for determining an increasing rate of the monitor voltage is set higher than that of the reference-voltage circuit for determining that of the reference voltage.

Abstract: A semiconductor device of the present invention includes: a power input terminal; an internal power supply circuit that converts a voltage supplied from the outside to the power input terminal into a predetermined voltage; an analog circuit connected to an output side of the internal power supply circuit; an internal power output terminal connected to the output side of the internal power supply circuit; a logic circuit power input terminal; a logic circuit connected to the logic circuit power input terminal; and interterminal wiring connecting the internal power output terminal to the logic circuit power input terminal. The internal power supply circuit has a configuration of supplying power to the analog circuit and the logic circuit, and in a package assembly (finished product), a resting current in the logic circuit can be inspected without being influence by a consumption current in the analog circuit.

Abstract: Consistent with an aspect of the present disclosure, a method is provided for controlling an AC signal, which is supplied to a load and selectively supplied to a utility grid. In response to a fault in the utility grid, the method includes decoupling the AC signal from the utility grid, and determining whether a voltage associated with the AC signal is within a desired band. The method also includes adjusting the voltage associated with the AC signal when the AC signal is outside the desired band, and comparing a magnitude of a current associated with the AC signal with a desired current value to thereby obtain a comparison result. In response to the comparison result, the current associated with the AC signal is adjusted when the voltage associated with the AC signal is within the desired band.

Abstract: In a power supply monitoring device, a power supply voltage monitoring portion always monitors a power supply voltage supplied to a monitored circuit and outputs a voltage reduction signal when detecting that the power supply voltage is reduced below a predetermined threshold (e.g. a second voltage higher than a voltage guaranteeing a normal operation of the monitored circuit and lower than a rated voltage). A monitoring controller having received the voltage reduction signal determines whether or not an operational malfunction has occurred in the monitored circuit by comparing operation data of the monitored circuit with reference data of the monitoring controller itself. Also, the monitoring controller executes recovery processing (reset processing or reference data overwrite processing) suitable for the monitored circuit referring to a prestored recovery processing type specific to the monitored circuit when detecting an operational malfunction of the monitored circuit.

Abstract: A circuit for protecting a motherboard of a computer includes a first transistor (Q1) and a second transistor (Q2). A CPU with a CPU voltage terminal (10) configured for electrically connecting to a power supply is mounted on the motherboard. A gate of the first transistor is connected to the CPU voltage terminal. A source of the first transistor is connected to ground. A gate of the second transistor is connected to a drain of the first transistor through a node (11). The node is at low level when the computer is off. A drain of the second transistor is connected to a control signal terminal (PWRBTN#) from the computer. When the computer is turned on and the CPU voltage terminal is not connected to the power supply and is at low level, the control signal terminal turns to low level from high level to turn off the computer.

Abstract: A power supply device has a pulse width control circuit for controlling voltage converting operation of a voltage converting circuit by changing a pulse width. A momentary interruption detecting circuit detects a change in an output voltage when the output voltage suffers a momentary interruption over a short period of time. A full short-circuit detecting circuit detects a change in the output voltage when the output voltage suffers a short circuit over a very short period of time. A short-circuit control circuit stops a pulse width changing control process of the pulse width control circuit a predetermined period of time after the momentary interruption detecting circuit has detected that the output voltage suffers a momentary interruption, and stops the pulse width changing control process of the pulse width control circuit immediately when the full short-circuit detecting circuit detects that the output voltage suffers a short circuit.

Abstract: To reduce the electric power wasted in an overvoltage protection circuit, a regulator IC 100 incorporates an overvoltage protection circuit 105 that stops the output operation of the regulator when the output voltage Vo becomes higher than a predetermined threshold voltage Vth1. The overvoltage protection circuit 105 includes switch means FET3 that turns on and off the overvoltage protection operation thereof according to a predetermined control signal.

Abstract: A test device is provided for testing stability of a computer when the computer is started up or shut down. The test device includes a monolithic chip and a switch module. The monolithic chip includes an input port and an output port. The input port receives a high level or a low level signal from the computer. A test control module is disposed in the monolithic chip. The switch module includes an input pin coupled to the output port of the monolithic chip and a pair of output pins corresponding to the input pin. The pair of output pins is connected to the computer, for controlling the computer to be started up or shut down. The input port of the monolithic chip is connected to the computer for detecting a state of the computer.

Abstract: A low voltage detect circuit is provided herein for detecting when an external voltage (Vext) drops below a predetermined minimum voltage. In general, the low voltage detect circuit described herein may be configured to detect a low voltage condition based on a threshold voltage difference between a non-zero threshold transistor having a substantially non-zero threshold voltage, and a zero threshold transistor having a threshold voltage relatively close to zero. According to a particularly advantageous aspect of the invention, the low voltage detect circuit described herein comprises substantially no resistors or reference voltage generation circuits, and therefore, provides significant savings in both current and die area consumption without sacrificing accuracy. The low voltage detect circuit of the present invention is particularly useful in power regulators, such as those used in memory systems or devices.

Abstract: A control circuit for a DC-DC converter that prevents a deficiency from occurring due to sudden interruption in power supply. The control circuit activates and inactivates a main switching output transistor and a synchronous rectification output transistor to convert the input voltage to an output voltage. The output voltage is smoothed by a smoothing capacitor. When the input voltage decreases, the control circuit activates the synchronous rectification output transistor to readily discharge the smoothing capacitor via the synchronous rectification output transistor.

Abstract: According to the invention, in order to suppress a latch-up, the supply voltage is switched off following the detection of a latch-up, charge located in the circuit is reduced with the air of a short-circuiting switch, and the detection of a low voltage is temporarily canceled when the supply voltage is gradually increased again. A protective circuit is assigned to an electronic circuit in order to protect the radiation-sensitive components thereof, the electronic circuit being subdivided into groups of active circuit components accepting a similar amount of current in a predefined area and a protective circuit being assigned to at least one of the groups of active circuit components accepting approximately the same amount of current in a predefined area. In order to prevent the output current from influencing the output voltage, a current-detecting unit is mounted upstream of a voltage-regulating unit.

Abstract: A method and a device for shutting down a drive during a power outage are disclosed. The method and device include a matrix converter, several commutation capacitors on the power line side, a switch unit on the power line side and a resistor unit. During a power outage, the matrix converter is immediately disconnected from the power supply, and the resistor unit is connected to the input terminals of the matrix converter in such a way that the amplitude of a voltage applied to the resistor unit equals the amplitude of an actual capacitor voltage space vector, and the speed setpoint is set to zero. This enables a drive with a matrix converter to be shut down during a power outage by way of a pulsed resistor.

Abstract: A low voltage interrupt for an electric winch prevents voltage decay of a battery due to excessive operation of the winch. If the battery voltage decays below a threshold, the low voltage interrupt disables the winch, allowing an alternator to recharge the battery. A voltage sense circuit determines the voltage of the battery. The sensed voltage is compared to a predetermined threshold. If the sensed voltage decays below the threshold, the low voltage interrupt generates an interrupt signal. The interrupt signal causes a relay to actuate, thereby interrupting current to the winch.

Abstract: An analog or digital circuit that senses both low and high input voltage and operates to disconnect both line and neutral electrical power connections to a protected device when abnormally low or high voltages are received from a single- or multi-phase power source, and reconnects the protected device when input power has stabilized. The sensing circuit and power supply is functional with voltages up to at least 240 Vac. The nominal 120 Vac circuit is designed to withstand a 6 kilovolt surge without damage. The apparatus does not disconnect the ground line during an out-of-tolerance voltage condition.

Abstract: This power detection circuit is comprised of a power-down detection circuit for detecting the first detection level and a power-on detection circuit having the second detection level higher than the first detection level, and the power detection circuit compulsorily initializes a power-on latch circuit by the output signal lowlevelx of the power-down detection circuit and also initializes the power-down detection circuit and the power-on detection circuit by the switch of a starter circuit.

Abstract: The invention provides a short-circuit protective circuit for a constant-voltage power-supply circuit. The constant-voltage power-supply circuit can realize a short-circuit protection with a simple circuit configuration in a power-supply circuit provided with a plurality of power-supply lines. A regulator is connected to one of a plurality of power-supply lines, and a constant voltage is outputted from an output terminal of the regulator through an output line. An output voltage from the regulator is inputted to constant-voltage circuits as a reference voltage, and output constant voltages from the constant-voltage circuits are supplied to the other output lines. A voltage detection circuit is connected to the other output lines, wherein if a voltage drop occurs in any output line, a detection signal is outputted to an operation circuit, thereby turning off an output control terminal of the regulator. Accordingly, the output of the regulator is stopped so that all of the output lines are stopped all at once.

Abstract: Methods and apparatuses for fault condition protection of a switched mode power supply. In one aspect of the invention, a power supply circuit having an auto-restart function to turn the power supply on and off repeatedly under fault conditions is included. In one embodiment, one or more off-times following detection of a fault condition is smaller than subsequent off-times.