Abstract: In one embodiment, a power supply controller is configured to reset or override a soft-start reference signal responsively to the output voltage decreasing to a value that is less than a desired regulated value of the output voltage.

Abstract: One embodiment of the present invention includes a system for providing a soft-start for a power regulator comprising a differential transistor pair that receives an input current and conducts a first current through a first transistor and a second current through a second transistor. One of the first and second current changes in response to a change in the other to maintain a sum of the first and second current being substantially equal to the input current. The system also comprises a comparator that provides an output signal based on a comparison of a first input voltage and a second input voltage associated with the first current and the second current, respectively. The system further comprises a current source activated by the output signal to charge a capacitor that increases a soft-start reference voltage associated with control of the power regulator and which controls the change in the other of the first and second current.

Abstract: A startup circuit for providing a startup voltage from a high voltage DC bus voltage to an application circuit, the startup circuit comprising an integrated circuit package for at least a control circuit for driving at least one power switch of the application circuit having a low voltage terminal; a dropping resistor in the integrated circuit package having a first terminal for coupling to the high voltage DC bus and a second terminal, the dropping resistor dropping the high voltage DC bus voltage to a reduced voltage and providing the reduced voltage at the second terminal; further comprising a low voltage regulator coupled to the second terminal for using the reduced voltage for enabling generation of a regulated startup low voltage DC output at a preset level at the low voltage terminal for powering at least one part of the application circuit during startup of the application circuit, wherein the high voltage DC bus voltage is the only voltage source provided externally to the integrated circuit package.

Abstract: In a capacitor charging apparatus, an on-time in which the primary circuit of a transformer is energized is continued until a primary current detection signal reaches a predetermined peak detection level, and an off-time in which the primary circuit is de-energized is clocked from the time when the primary current peak detection signal is received. At the end of the clocking, an ending signal is generated to terminate the off-time. The length of an off-time is inversely proportional to the charging voltage across the capacitor. The length of an off-time may be altered using a regulation resistor. Thus, an on-time and an associated off-time of the primary circuit of the transformer are controlled independently to optimize charging time and power efficiency of the charging.

Abstract: A soft start circuit includes a constant current source for generating a constant current, a first current mirror circuit for generating from the constant current a first mirror current, a second current mirror circuit for generating from the constant current a second mirror current smaller than the first mirror current, and a capacitor into which a difference between the first mirror current and the second mirror current is introduced, wherein a divided voltage of a charging voltage thereof is output as a soft start voltage. The soft start circuit provides a gradual soft start voltage.

Abstract: An improved start-up circuit and method for self-bias circuits is described that applies a start-up voltage and current to a self-bias circuit to initialize its operation in its desired stable state. Once the self-bias circuit converges to its desired state of operation a start-up voltage reference/voltage clamping circuit shuts off current flow to the self-bias circuit and the start-up circuit enters a low power mode of operation to reduce its overall current and power draw. This allows for embodiments of the present invention to be utilized in portable and/or low power devices where low power consumption is of increased importance. In one embodiment of the present invention, a band-gap voltage reference circuit is initiated utilizing a start-up circuit.

Abstract: For soft start of a switching regulator, the output voltage of the switching regulator is fed back to be compared with a ramp signal, in order to trigger a comparison signal when the ramp signal rises up to reach the feedback signal, to enable the switching regulator such that the output voltage changes from a residual voltage toward a target value. The low side switch of the switching regulator is kept off for a period of time after the switching regulator is enabled, so as to prevent a reverse current during the soft start period.

Abstract: Charge storage devices (e.g., batteries or supercapacitors) need to be charged from time to time. In an apparatus, to protect a charge storage device as well as the supply used to charge it, the apparatus typically includes power loop control circuitry. One approach to implementing the power loop control employs a temperature sensor in combination with soft start circuitry in order to protect the circuitry from a rapidly increasing temperature when charge current increases. The soft start circuitry allows for controlled step-wise increase and regulation of the current. The approach preferably allows for selecting the number and resolution of such incremental steps. Various embodiments of the invention include devices and methods for controlling power and may take into account temperature in step-wise regulation of the charge current.

Abstract: A method and circuit for providing a controlled ramping and filtering to a reference voltage in a regulator circuit such that an inrush current is limited and noise coupling to an output voltage is reduced. In a typical regulator circuit a soft-start and filter circuit is inserted between a feedback amplifier and a charge transfer circuit. The soft-start and filter circuit comprises a pair of transistors that are arranged to operate as a current mirror, a biasing current source determining the current drawn from the current mirror, and a soft-start capacitor shunted by a third transistor providing a conditioned reference voltage. When reference voltage rises rapidly during power-up, charging of the soft-start capacitor with constant current provides a soft-sloped conditioned reference voltage. In steady state, soft-start capacitor and a resistance of the transistor provide a first order low pass filter reducing noise that couples to the reference voltage.

Abstract: A step-up power supply device includes: a step-up converter; a startup circuit which controls the on/off operation of a switch element of the step-up converter when an output voltage of the device is smaller than a reference voltage; and a control circuit which operates in substitution for the startup circuit when the output voltage is higher than the reference voltage to control the on/off operation of the switch element such that the output voltage reaches a target value.

Abstract: In one embodiment, an apparatus is provided for a system including an integrated circuit coupled to a node to receive a supply voltage and having bypass capacitors coupled in parallel with the integrated circuit to the node. The apparatus comprises a first capacitor, a switch coupled to the first capacitor, and a voltage source configured to charge the first capacitor. The switch is coupled to receive a control signal that is asserted, during use, if the supply voltage to an integrated circuit is to be increased. The switch is configured to electrically couple the first capacitor to the node in response to an assertion of the control signal. When electrically coupled to the node, the first capacitor supplies charge to the bypass capacitors. A system comprising the apparatus, the node, the integrated circuit, and the bypass capacitors is also contemplated in some embodiments.

Abstract: A technique includes using a first stored energy source to generate a reference signal to circuitry of a supply regulator in response to the regulator being in a startup state. The technique includes using an output signal that is provided by the regulator to generate the reference signal in response to the regulator not being in the startup state.

Abstract: A start-up circuit is provided. In one embodiment, the start-up circuit operates as follows. In this embodiment, the start-up circuit includes a depletion-mode PMOS transistor and an NMOS switch. The NMOS switch is coupled between ground and a common gate node of a PMOS current mirror. At start-up, the depletion-mode transistor provides a DC path to pull up the gate of the NMOS switch. Accordingly, at start-up, the NMOS switch pulls the common gate of the PMOS current mirror to ground. After the PMOS current mirror begins generating current, the NMOS switch is turned off.

Abstract: A bandgap voltage generating circuit includes a circuit coupled to a first node and a second node, driving the first and the second nodes to the same voltage level. A first impedance element is coupled to the first node and a second impedance element is coupled to the second node, wherein the impedance of the second impedance element is larger than the impedance of the first impedance element. A first transistor is coupled to the first impedance element, and a second transistor is coupled to the second impedance element and the first transistor. The bandgap generating circuit generates a bandgap voltage at the second node.

Abstract: A method capable of sensing a heavy load and a short circuit of a low dropout regulator includes providing a ramp pulse signal to the low dropout regulator, providing a square waveform, comparing a feedback signal of the low dropout regulator with the square waveform, and determining the low dropout regulator is a heavy load or a short circuit if a duration that the feedback signal is greater than a low voltage level of the square waveform and lower than a high voltage level of the square waveform is not greater than a pulse width of the square waveform. The method includes determining the low dropout regulator is a light load if the duration that the feedback signal is greater than the low voltage level of the square waveform and lower than the high voltage level of the square waveform is greater than the pulse width of the square waveform.

Abstract: A regulator is provided. In one embodiment, the regulator operates as follows. During steady-state conditions, the switching frequency is maintained substantially constant. During start-up and/or in response to an over-current event, the reference voltage is attenuated. For example, in one embodiment, during a soft-start, the reference voltage ramps upward. During the soft-start, the switching frequency is attenuated in proportion to the attenuation of the reference voltage. The switching frequency is attenuated by skipping a number of pulses that is proportional to the reference voltage attenuation, or through another method. In another embodiment, a dynamic over-current protection scheme is employed.

Abstract: A reference circuit. Included are first and second reference circuit blocks, first and second controllable current sources connected to supply current through the first and second reference circuit blocks respectively, an amplifier having non-inverting and inverting inputs responsive to the voltages developed by the first and second reference circuit blocks respectively and having an output connected to control the currents provided by the first and second current sources, and an output stage having a reference output controlled by the output of the amplifier. The reference circuit further comprises start-up circuitry, including a latch having an output indicating its state and being responsive to a signal indicative of the output from the reference output to latch from a first state into a second state when that signal passes a first threshold, and a switch that is responsive to the output of the latch to supply a control signal.

Abstract: A synchronous rectifying type switching regulator control circuit has a first reference voltage circuit that receives a soft start signal from a soft start circuit and outputs a first reference voltage. An error amplifying circuit amplifies a difference of the first reference voltage and a divided voltage from a voltage dividing circuit and outputs an error voltage Verr. A first comparing circuit compares a triangular wave from an oscillator with the error voltage Verr and outputs an output pulse Vcomp. A second comparing circuit compares a second reference voltage from a second reference voltage circuit with the error voltage Verr and outputs a voltage ERRcomp. A logic circuit receives the soft start signal, the output pulse Vcomp, and the voltage ERRcomp and outputs a voltage Vcomp2. The logic circuit outputs the output pulse Vcomp when the error voltage Verr is higher than the second reference voltage during a soft start period.

Abstract: A startup circuit for activating a bandgap circuit is provided, including a switching circuit, an activating circuit, and a controlling circuit. The controlling circuit is used for monitoring and comparing two voltages to determine whether the switching circuit should be turned on so as to activate the bandgap circuit. One of the two voltages that are monitored is a zero temperature coefficient voltage, and the other of the two voltages that are monitored is a negative temperature coefficient voltage.

Abstract: A switching mode power supply and method for generating a bias voltage is described. The bias voltage is generated by using a current source coupled to a primary coil of a transformer during the start-up of the switching mode power supply. The generation of the bias voltage through the current source is stopped at a second time, a delay time after a first time when the bias voltage becomes essentially equal to a reference voltage that is an operational voltage of a PWM controller. The switching operation of a main switch is started after the first time, when the bias voltage exceeded the operational voltage. In this interval the bias voltage is also generated by the secondary coil of the transformer.

Abstract: A circuit and method for soft start of a system compare a feedback signal produced from an output voltage of the system with a ramp signal to generate a comparison signal, and enables the system once the comparison signal indicating the ramp signal reaches the feedback signal, such that the output voltage becomes active from a residual voltage toward a target level.

Abstract: A circuit for generating a reference current comprises: a first current mirror configured to current-mirror based on a second current, so as to generate a first current that is substantially in inverse proportion to a variation of a power supply voltage; a current compensation unit configured to remove a variation of the first current corresponding to the variation of the power supply voltage to form a compensated first current; a second current mirror configured to generate the second current based on the compensated first current, and configured to provide the second current to the first current mirror; and a current output unit configured to output the second current as the reference current.

Abstract: An inverter (100) comprises first and second input terminals (102,104), an inverter output terminal (106), a series arrangement of a first inverter transistor (110) and a second inverter transistor (120), a driver circuit (130), a primary current sensing circuit (150,154,156), and an auxiliary current sensing circuit (160). Primary current sensing circuit (150,154,156) is coupled between second inverter transistor (120) and a current-sense input (132) of driver circuit (130). Auxiliary current sensing circuit (160) is coupled between second inverter transistor (120) and a frequency control input (134) of driver circuit (130). During operation, if the current flow through inverter transistors (110,120) exceeds a predetermined peak limit, auxiliary current sensing circuit (160) provides an auxiliary signal to frequency control input (134) of driver circuit (130), thereby increasing a drive frequency at which driver circuit (130) commutates inverter transistors (110,120).

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: In one embodiment, a switching power supply controller decouples the power supply controller from receiving a sense signal during one portion of the operation of the power supply controller and couples the switching power supply controller to receive the sense signal during another portion of the operation.

Abstract: A pre-bias protection circuit for a converter circuit including a switching stage having high-and low-side switches connected in series at a switching node and an output stage connected to the switching node having a capacitor having a pre-existing pre-bias voltage at startup of the converter circuit, the pre-bias protection circuit controlling discharge of the pre-bias voltage when the low-side switch is turned ON during a start up of the converter circuit. The pre-bias protection circuit includes a first circuit for providing a first output; a second circuit providing a second output; and a comparator circuit for comparing the first output and the second output and producing a third output comprising a pulse width modulated signal for driving the low side switch such that the pulse width modulated signal starts with a small duty cycle and thereafter increases to a larger duty cycle, thereby to prevent the pre-bias voltage from discharging during startup.

Abstract: Embodiment of the present invention may provide a switching regulator which may be located within an IC. The switching regulator couples to an external power supply, a plurality of configurable control registers, a plurality of default registers, and a multiplexer. The multiplexer is operable to select an input control signal from either the plurality of configurable control registers or the plurality of default control registers as the output control signal to the switching regulator. This default control signal, although not optimal, allows the switching regulator to be configured in a default condition during start up or power down operations and ensures that the switching regulator may provide a stable, although not necessarily optimal, power output to the various components within the IC.

Abstract: An initial voltage establishing circuit has a current supplying circuit, a current adjusting circuit, a charge/discharge control circuit, and an oscillating signal generating circuit. The current supplying circuit provides a charge current and a discharge current. The current adjusting circuit adjusts the charge current and the discharge current. The charge/discharge control circuit selectively allows the charge current and the discharge current to flow through. The oscillating signal generating circuit employs the charge current and the discharge current to generate an initial voltage establishing signal such that a duty cycle of the initial voltage establishing signal gradually increases. The initial voltage establishing signal is applied to a switching voltage converter for establishing an initial output voltage.

Abstract: A low drop-out voltage regulator having soft-start. A low drop-out regulator circuit is provided having an input node, an output node, a power FET connected by a source and drain between the input node and the output node, and a feedback circuit having an output connected and providing a control signal to a gate of the power FET. A current limit circuit is configured to control the power FET to limit the current through it when the voltage across a controllable sense resistor connected to conduct a current representing the current through the power FET exceeds a predetermined limit value. At start-up, control unit provides a control signal to the controllable resistor to cause the resistance value of the controllable resistor to decrease incrementally in value at respective predetermined incremental times during a predetermined time interval.

Abstract: A control circuit for a PWM switching power regulator including an error amplifier and an amplifier filter circuit. The error amplifier has a first input receiving a reference signal, a second input receiving an output sense signal, and an output providing a compensation signal used to control PWM switching. The amplifier filter circuit has an input receiving a ratio-metric tracking signal and an output providing the reference signal to the input of the error amplifier. The control circuit may include a resistive voltage divider for providing the tracking signal. The amplifier filter circuit may be implemented as a transconductance amplifier having an input receiving the tracking signal and an output coupled to a capacitor. The transconductance amplifier may have a relatively small current drive capacity and its output may have a relatively slow and weak response to changes of the tracking signal.

Abstract: A booster circuit generates a boosted output by boosting a low voltage output supplied as a target to be boosted and feeds back a part of the boosted output, an output by the booster circuit itself, to the booster circuit as operation energy. An auxiliary booster circuit outputs start-up energy generated based on a low voltage output to the booster circuit as start-up energy that is necessary for starting up the booster circuit.

Abstract: A voltage conversion circuit and a switching power supply device achieving both a good response and a low loss of a power supply voltage, wherein a main voltage conversion portion (circuit block) for conversion an AC voltage to a DC voltage, an auxiliary voltage conversion portion for the same conversion but in transit period up to shifting to a stationary state, a voltage limiting portion (Zener diode) for limiting the DC voltage output from the auxiliary voltage conversion portion to a constant limit-voltage, and an output control switch (transistor) connected in the output pass and for switching the pass to conductive or nonconductive possible to apply a higher voltage in between a voltage at the output node and the limit-voltage based on their magnitude relation.

Abstract: A distributed power supply is incorporated in a device including a plurality of PCB. An on-board power supply is provided in the distributed power supply. The on-board power supply individually supplies a secondary power to each PCB using a primary power. Each PCB includes a primary power supply monitoring circuit, a PCB internal power supply monitoring circuit, and a pulse generation circuit. The primary power supply circuit detects an abnormality in the voltage of in the primary power supplied to the on-board power supply. The PCB internal power supply monitoring circuit restarts the PCB when the abnormality is detected. The pulse generation circuit transmits a restart signal to the other PCBs in the device.

Abstract: An electrical circuit that provides accurate, regulated output voltage over a wide range of input voltages, while exhibiting each of three desired characteristics: accuracy across different supply/process/temperature; stability and linearity yielding phase/gain margins; and high (good) power supply rejection ratio (PSRR). The circuit comprises an output node having a load current and an amplifier having a first input coupled to a reference voltage and receiving a bias input current that is a pre-established proportionate size of the load current across the output node, such that a change in the load current results in a proportionate change in the bias input current. The electrical circuit represents a voltage regulator that provides accurate, linear output voltage that is a predictable portion of the reference voltage.

Abstract: A system for controlling a soft start for a switching power converter includes a digital controller that enables the programming of a plurality of input voltage profiles during a soft start condition of the switching power converter. The programming of the plurality of input voltage profiles is parameterized by a control parameter. A microcontroller determines the control parameter used by said digital controller and operates independently of the operation of the digital controller.

Abstract: An inverter and inverter driving method enable slow start of a load by gradually increasing the lamp current within a range less than a predetermined maximum level, thereby preventing improper operation of the inverter. The inverter includes a transformer for converting a DC input voltage into an AC output voltage, an inverter control unit for controlling a level of the AC output voltage from the transformer in response to a feedback current from a load driven by the AC output voltage, and a kick-off control unit for adjusting the feedback current during a kick-off period for starting the load.

Abstract: A soft start circuit includes a constant current source for generating a constant current, a first current mirror circuit for generating from the constant current a first mirror current, a second current mirror circuit for generating from the constant current a second mirror current smaller than the first mirror current, and a capacitor into which a difference between the first mirror current and the second mirror current is introduced, wherein a divided voltage of a charging voltage thereof is output as a soft start voltage. The soft start circuit provides a gradual soft start voltage.

Abstract: An electrical circuit that provides accurate, regulated output voltage over a wide range of input voltages, while exhibiting each of three desired characteristics: accuracy across different supply/process/temperature; stability and linearity yielding phase/gain margins; and high (good) power supply rejection ratio (PSRR). The circuit comprises an output node having a load current and an amplifier having a first input coupled to a reference voltage and receiving a bias input current that is a pre-established proportionate size of the load current across the output node, such that a change in the load current results in a proportionate change in the bias input current. The electrical circuit represents a voltage regulator that provides accurate, linear output voltage that is a predictable portion of the reference voltage.

Abstract: A start-up circuit includes a long channel current generator, a subtracting reference current generator, and a gain scaling current mirror-circuit. The long channel current generator circuit uses a long channel transistor circuit that simulates a high value resistor to provide a low-level current. The low-level current is sensed by the subtracting reference current generator to provide a reference current that tracks the low-level current until a diverting current is activated, where the diverting current is subtracted from the reference current such that the reference current increases at a slower rate than the low-level current for increasing supply voltages. The gain scaling current mirror-circuit generates the start-up current as a gain scaled version of the reference current. Once the bias generator circuit is active, a stop-current can be used to shut down the gain scaling current mirror-circuit to conserve current.

Abstract: A reference circuit can include a reference section that provides a reference value for other circuits of an integrated circuit and can be enabled and disabled in response to an enable signal. The reference circuit can include at least a first node, draw a reference current in the enabled mode, and draw essentially no current in the disabled mode. A pulse start-up section can provides a low impedance path between the first node and a first potential for a predetermined duration in response to the reference circuit being enabled. A continuous start-up section can provide a low impedance path between the first node and the first potential based on a logic state of an enable signal.

Abstract: The proposed boost circuit includes a DC/DC converter having a switch, receiving an input voltage and outputting an input voltage feedback signal, an output voltage feedback signal, an input current feedback signal and an output voltage after a boost of the input voltage, and a feedback control circuit having a pulse-width modulation limiting controller, coupled to the converter, receiving the input voltage feedback signal, the output voltage feedback signal and the input current feedback signal and generating an output signal with a fixed time period. The output signal is employed to control the switching of the switch so as to generate the boost.

Abstract: A PWM (pulse width modulation) boost system includes a boost circuit, a voltage dividing circuit, a comparator, a PWM circuit, a pre-oscillator, and a current limit circuit. A start-up method of the PWM boost system includes (1) providing an error voltage; (2) generating a PWM signal according to the error voltage; (3) controlling a switch in a boost circuit with the PWM signal, so as to control an inductor current flowing through a boost inductor in the boost circuit; (4) charging a capacitor in the boost circuit with the inductor current, wherein charges stored in the capacitor define a DC output voltage; and (5) providing a feedback voltage according to the DC output voltage to adjust the error voltage.

Abstract: A polyphase AC induction motor is connected to a power supply through a soft starter having three sets of inverse parallel connected silicon controlled rectifiers with each set corresponding to one particular phase. Low speed starting and operation of the motor can be accomplished through triggering circuits controlling the phases of the triggering pulses in relation to the phases of the supply. The low motor speeds are developed by a gating sequence that generates a low frequency waveform that is less than the main supply frequency to the motor. This low frequency waveform is current and voltage controlled by the gating sequence to permit the AC motor to smoothly operate at speeds less than 100% of rated while developing net positive torque at the low controlled operating frequency.

Abstract: A booster circuit generates a boosted output by boosting a low voltage output supplied as a target to be boosted and feeds back a part of the boosted output, an output by the booster circuit itself, to the booster circuit as operation energy. An auxiliary booster circuit outputs start-up energy generated based on a low voltage output to the booster circuit as start-up energy that is necessary for starting up the booster circuit.

Abstract: A power efficient startup circuit for activating a bandgap reference circuit is disclosed. The startup circuit uses a voltage supply having a voltage level to initiate the flow of a startup current used to activate the bandgap reference circuit. When the bandgap reference circuit starts, the startup circuit slowly charges a capacitor using the voltage supply when the startup current is flowing. The startup circuit disables quiescent current when the bandgap reference circuit is activated and a voltage of the capacitor exceeds a value equal to the difference between the voltage of the voltage supply when powered on and a voltage threshold of a switching device which disables the quiescent current. The capacitor is discharged when the voltage supply is turned off.

Abstract: A circuit includes a current generator, a start-up circuit coupled to provide a start-up current to the current generator during a start-up phase of the current generator, and a cut-off circuit coupled to both the current generator and to the start-up circuit to provide a control signal that reduces the start-up current when an output current from the current generator exceeds a threshold value.

Abstract: The smart start-up circuits basically include a sensor, two stacked PMOS transistors, two stacked NMOS transistors, and a feedback line. If the sensing voltage does not reach the expected voltage compared to the midpoint voltage of the sensor, the output voltage of the sensor turns on the corresponding transistor, which provides a current to its output until the voltage at feedback reaches the midpoint voltage. The time to reach the midpoint voltage at a load is simply equal to the charge stored at the load divided by the current, which can be scaled by a device aspect ratio of the transistor. Consequently, all smart start-up circuits provide an initial output voltage level closer to the output voltage level that reaches the equilibrium according to schedule.

Abstract: An electronic circuit is connected between input lines of an alternating input power supply and input lines of a boost converter to limit an input inrush current and/or an output short-circuit current supplied to the boost converter in a power supply. The electronic circuit includes a rectifier circuit to rectify alternating input current of the alternating current power supply, and a feedback circuit for feeding back a switching signal to the rectifier circuit circuit to switch the rectifier circuit on and off.

Abstract: An electrical power converter system adjusts a wakeup voltage periodically, to permit earlier connection and/or operation, to increase performance. The electrical power converter system selects between a mathematically adjusted wakeup voltage based on at least one previous period, and a table derived wakeup voltage that takes into account historical information. The electrical power converter system is particularly suited to applications with periodicity such as solar based photovoltaic power generation.

Abstract: An improved start-up circuit and method for self-bias circuits is described that applies a start-up voltage and current to a self-bias circuit to initialize its operation in its desired stable state. Once the self-bias circuit converges to its desired state of operation a start-up voltage reference/voltage clamping circuit shuts off current flow to the self-bias circuit and the start-up circuit enters a low power mode of operation to reduce its overall current and power draw. This allows for embodiments of the present invention to be utilized in portable and/or low power devices where low power consumption is of increased importance. In one embodiment of the present invention, a band-gap voltage reference circuit is initiated utilizing a start-up circuit.