Abstract: In a light power generation system, a control device, a control method, and a program, efficient power can be supplied. The maximum power detection unit operates a MOSFET in a power converter circuit and open-circuits both ends of a solar cell panel in the maximum power detection mode. After that, the maximum power detection unit short-circuits both ends of the solar cell panel, detects a maximum power by monitoring the output power of the solar cell panel during a period from the open state to the short-circuited state, and defines the voltage of the solar cell panel as an optimal voltage when detecting the maximum power. In a tracking operation mode, the control unit performs PWM control with respect to the MOSFET by defining the optimal voltage to be a reference signal. Operations are repeated between the maximum power detection mode and the tracking operation mode.

Abstract: A voltage converter includes a voltage converting circuit, a pulse width modulation (PWM) controller, a feedback circuit, an adjusting circuit, and a measuring circuit. The voltage converting circuit converts an input voltage to a low output voltage for a load. The PWM controller includes a comparator and a triangular-wave oscillator. The comparator is connected to the voltage converting circuit and outputs a PWM voltage to the voltage converting circuit. The triangular-wave oscillator is connected to an inverting terminal of the comparator, and outputs a sawtooth-wave voltage to the comparator. The feedback circuit is connected to a non-inverting terminal of the comparator and outputs a feedback voltage to the comparator. The measuring circuit measures current output from the voltage converting circuit and controls the adjusting circuit to provide a pull-up voltage to the triangular-wave oscillator when the measured current decreases, thereby increasing the duty ratio of the PWM voltage.

Abstract: The present invention discloses a power factor correction circuit, a control circuit therefor and a method for driving a power factor correction circuit. The power factor correction circuit receives rectified power obtained by rectifying AC power, and corrects the power factor thereof. The power factor correction circuit includes an inductor, and it generates a reference signal as a limit for the inductor current. The reference signal is proportional to Comp/Vin, wherein Comp is a signal relating to a feedback signal, and Vin is a voltage signal relating to the AC power or the rectified power.

Abstract: There is provided a control device which controls a transformer in accordance with a total loss imposed on a load driving system including the transformer and a load.

Abstract: A power supply includes an inputter including an input capacitor and configured to receive an input DC voltage, a converter including an output capacitor and configured to convert the input DC voltage and to output the converted DC voltage, and a controller configured to control the converter to output a voltage corresponding to a reference voltage.

Abstract: A switching regulator switch between an input terminal and an output terminal; a second switch between the output terminal and ground; a switching-time control circuit to generate a first signal when a first period corresponding to a ratio of ON-period of the first switch to a sum of those of the switches has elapsed from a reset-release timing and a reset signal when a second period longer than the first period has elapsed from the rest-release timing; a comparator to generate a second signal when a feedback voltage is smaller than a reference voltage; and a switch control circuit to control the switches so that the first switch is turned off and the second switch is turned on in response to the first signal, and the second switch is turned off and the first switch is fumed on in response to the second signal.

Abstract: A device and method of providing any one of a plurality of desired levels of a regulated signal output to a load is described, wherein each desired level is a function of a corresponding reference signal. The device is configured and the method is designed to (1) store each desired level of the regulated signal output on a switchable storage device; and (2) selectively switch the correct storage device to the output when switching from one regulated state to another so as to establish the desired level of regulated signal output.

Abstract: A predictive current feedback system for a switched mode regulator including a sample and hold network for sampling voltage across a lower switch of the regulator and for providing a hold signal indicative thereof, and a predictive current feedback network which adds an offset adjustment to the hold signal based on a duration of a pulse width of a pulse control signal developed by the regulator. Sampling may be done while the lower switch is on for providing a hold value indicative of inductor current while the pulse control signal is low. The offset adjustment may be added to the hold signal in response to a transient event when the pulse signal is high. The offset may be incremental values after each of incremental time periods after a nominal time period, or may be a time-varying value. Adjustment may be made while the pulse signal is low as well.

Abstract: An error determination module determines a voltage error based on an output voltage of a DC to DC converter, an estimated output voltage of the DC to DC converter, and a product of a predetermined delay value and a difference between a duty cycle and a target voltage. A capacitor current determination module determines a capacitor current based on the voltage error. A capacitor voltage determination module determines a capacitor voltage based on the voltage error. A duty cycle module sets the duty cycle for a sampling period based on the capacitor current and the capacitor voltage. A pulse width modulation (PWM) module controls a switching duty cycle of the DC to DC converter based on the duty cycle.

Abstract: A DC-DC converter, having an input voltage and an output voltage, includes an inductor and a switch switching the input voltage to an input side of the inductor, where a feedback path controlling initiation of closing the switch includes capacitive coupling of the voltage at the input side of the inductor.

Abstract: A switching regulator includes a multiphase converter which includes a plurality of main phases configured to covert a power supply voltage to a lower voltage for application to an electronic device at different load conditions. The switching regulator also includes an auxiliary phase configured to operate in a pulse frequency modulation mode during a light load condition so that power is supplied to the electronic device by at least the auxiliary phase during the light load condition.

Abstract: A wide input voltage power supply circuit for a load includes a first regulation stage and a second regulation stage. The first regulation stage includes a linear regulator circuit configured to maintain a bus voltage within a predefined voltage range when an input voltage exceeds a predefined input level. A second regulation stage includes a buck converter circuit configured to regulate an average bus voltage to a predetermined load level. The second regulation stage includes an under voltage lockout configuration, with the under voltage lockout configured to set a minimum turn-on voltage for the load.

Abstract: High bandwidth, low noise switching power supply operating in quasi-resonant mode for filtering switching harmonic noise, while providing a fast control bandwidth and power at high efficiency. The power supply has an LCL tank defining a resonance period Ttank, and a switching circuit regulation loop for turning on its switching circuit for on-time tON commencing at a time based on a state of regulation of the power supply. A switching capacitor current sensor triggers the switching circuit to turn off at the end of the resonance period Ttank, whereupon the switching and output inductors enter a discharging phase for a period not related to resonance period Ttank. “Quasi-resonant” operation, where the power supply is in resonant mode during on time tON and not in resonant mode during off time tOFF ensures that the output inductor filters the switching harmonic noise of the switching circuit.

Abstract: A control circuit for a discontinuous conduction mode power factor correction converter using harmonic modulation includes: a first difference circuit configured to calculate and output a difference between an output voltage of a discontinuous conduction mode power factor correction converter and a reference voltage; a PI converter configured to perform a proportional integral control on an output signal of the first difference circuit, and output a signal having an arbitrary duty ratio; a second difference circuit configured to output a difference between a rectified input voltage, which is input to the discontinuous conduction mode power factor correction converter, and a harmonic modulation factor DC voltage; and a multiplication circuit configured to multiply an output of the PI controller and an output of the second difference circuit, and output a PFC control signal to a switch of the discontinuous conduction mode power factor correction converter.

Abstract: One embodiment provides A DC-DC converter system that includes a high side switch and a low side switch coupled to a power supply, each switch is configured to transition from an on state to an off state and from an off state to an on state to deliver current to an inductor and a load. This embodiment also includes low side driver circuitry configured to control the conduction state of the low side switch and configured to drive the low side switch with a first gate driving signal during a first mode of operation and with a second gate driving signal during a second mode of operation. The first gate driving voltage is stronger than the second gate driving signal and the second gate driving signal is configured to cause a slower switch transition of the low side switch compared to the first gate drive control signal.

Abstract: A switching regulator has an output circuit having first and second transistors and a connection node thereof as an output terminal; a switching control unit generating a first and second switching pulses for alternately switching the first and second transistors according to the load; and a first comparator monitoring an output voltage, and generating a pulse stopping control signal for stopping the generation of the switching pulses when the output voltage rises, and for generating the switching pulses when the output voltage drops. And the switching control unit performs a stopping operation for stopping the switching pulse generation and a switching operation for generating the switching pulse in response to the pulse stopping control signal, and outputs, to the first comparator, a timing control signal for quickening a switching timing from the stopping operation to the switching operation as the load of the load circuit increases.

Abstract: A current-mode regulator relies on indirect current measurement to facilitate slope compensation used to stabilize the operation of a buck converter. The current-mode regulator comprises an inductor, a switching network, and a controller. The inductor delivers an output current to a load. The switching network selectively connects the inductor input to an input voltage or a second voltage. The regulator controls the switching network. An inner loop control circuit of the regulator comprises the switching network, a current measuring circuit, a slope circuit, a comparator, and a switching controller. The current measuring circuit comprises a passive network connected to the inductor input and operative to indicate an inductor current as a measurement voltage. The slope circuit applies a time-varying voltage having a positive slope to the measurement voltage. The comparator compares a slope compensated measurement voltage to the control voltage.

Abstract: A multi-phase power block for a switching regulator includes a phase control circuit, N power cells and a current sharing control circuit. The phase control circuit is configured to receive a single phase PWM clock signal and generate N clock signals in N phases. Each of the N power cells includes a pair of power switches, gate drivers, a control circuit receiving one of the N clock signals and generating gate drive signals for the gate drivers, and an inductor. The current sharing control circuit is configured to assess the inductor current at the inductor of the N power cells and to generate duty cycle control signals for the N power cells. The duty cycle control signals are applied to the control circuits to adjust the duty cycle of one or more clock signals supplied to the power cells to balance a current loading among the N power cells.

Abstract: A switching control circuit includes driving a flow of direct current through an at least partially inductive load. The switching control circuit is adapted for adjusting a control current in order to activate and/or deactivate a flow of current to a load terminal. The system comprises a timer element for initiating at least one timed adjustment of the control current during activation or deactivation of the flow of current through a first semiconductor switch of the circuit so as to anticipate a state change of a component of the switching control circuit. The controller is adapted for determining a timing for the timed adjustment in a predictive manner. A method employs the various features of the switching control circuit.

Abstract: A DC-DC converter includes a drive circuit configured to drive a first switching element, and a second switching element coupled between a low potential power terminal of the drive circuit and a first node corresponding to the input voltage or the output voltage. A current detecting section detects a load current flowing in the output terminal. A control circuit turns on a third switching element, which is coupled between the low potential power terminal of the drive circuit and a second node having a potential lower than both the input voltage and the output voltage, in a case where a difference between the input voltage and the output voltage is lower than a threshold. The control circuit controls the second and third switching elements based on a detection result of the current detecting section in a case where the difference is equal to or greater than the threshold.

Abstract: Disclosed is a switched-mode power supply including an inductor which is connected between a voltage input terminal to which a DC voltage is input and an output terminal to which a load is connected, a driver switching element which intermittently feeds a current to the inductor and a control circuit which generates a control pulse according to a feedback voltage from output side and controls on/off of the driver switching element. The control circuit includes a voltage comparison circuit which compares the feedback voltage to a predetermined voltage and a pseudo ripple generator circuit which generates a pseudo ripple voltage having a predetermined amplitude, and the control circuit injects a ripple component in a transmission path of the feedback voltage based on the pseudo ripple voltage generated by the pseudo ripple generator circuit.

Abstract: A power supply uses a power converter to generate a regulated voltage by referencing to a first DC voltage, a low dropout (LDO) regulator to generate an output voltage from the regulated voltage by referencing to a second DC voltage, and a reference voltage generator to dynamically adjust the first DC voltage according to the input voltage and the control voltage of the output transistor of the LDO regulator. The dropout voltage of the LDO regulator can be minimized to maintain the high efficiency of the power supply at different loading or selected output voltages.

Abstract: A power supply apparatus includes a first power factor correction circuit, a second power factor correction circuit and a control circuit that includes a first switching control unit that outputs a first switching signal for controlling a first switching element of the first power factor correction circuit generated in accordance with a detected result by an output voltage of the first power factor correction circuit and a current flowing through the first switching element, and a second switching control unit that outputs a second switching signal for controlling a second switching element of the second power factor correction circuit generated in accordance with a detected result by an output voltage of the second power factor correction circuit and a current flowing through the second switching element.

Abstract: An error amplifier and a driving circuit are disclosed herein. The error amplifier is configured to charge a compensation capacitor with an error current. The error amplifier includes an input stage, a main output stage, and an auxiliary output stage. The input stage is configured to provide a first differential output signal and a second differential output signal in response to a comparison between a reference voltage and a feedback voltage. The main output stage is configured to charge the compensation capacitor. The auxiliary output stage is configured to be activated to charge the compensation capacitor. In a first operation, both the main output stage and the auxiliary output stage charge the compensation capacitor. In a second operation, the main output stage charges the compensation capacitor, and the auxiliary output stage is deactivated and does not charge the compensation capacitor.

Abstract: A current mode buck converter has a power stage and a feedback stage. The power stage converts a higher power supply voltage level to a lower output voltage level. The feedback stage is connected with the power stage for controlling the levels of repetitive switching of an output current by phase and frequency locking a switching frequency of the output current to an external clocking signal. The feedback stage controls two levels of output current bounds by transforming a current error to a phase error to prevent error amplification such that an average output current remains constant at any duty cycle.

Abstract: A dynamic voltage response network for a switching regulator with droop control providing a droop control signal includes a voltage identification setting network, a pass and hold system, and a reset network. The voltage identification setting network initiates a hold condition and adjusts an output voltage reference in response to a change in a voltage identification input. The pass and hold system passes the droop control signal during a pass condition and holds the droop control signal during the hold condition. The reset network resets the pass and hold system to the pass condition in response to a reset signal. The reset signal may be provided in response to a variety of conditions, such as load transients, proximity between the developed droop control signal and the held droop control signal, timeout after the output voltage reference is adjusted, among other reset conditions.

Abstract: A switching converter and a load regulation compensation module for improving load regulation accuracy of the switching converter. The switching converter regulates its output voltage through controlling a switch module to switch on and off based on a first reference signal and a feedback signal indicative of the output voltage. The on and off switching of the switch module generates a switching current, resulting in an average offset voltage between an internal reference ground and a package ground pin of the switching converter. The load regulation compensation module is configured to monitor the switching current, and to compensate a second reference signal having a bandgap reference voltage referenced to the internal reference ground based on the monitored switching current to generate the first reference signal, so that the average offset voltage is substantially cancelled out from the first reference signal with respect to the package ground pin.

Abstract: A control circuit controls a power output module and drives a load device. The control circuit includes a conversion unit, a feed-forward unit, a feedback unit and a control unit. The conversion unit generates a driving signal according to an output signal of the power output module for driving the load device. The feed-forward unit generates a duty cycle reference signal according to the output signal. The feedback unit generates a feedback signal according to the driving signal. The control unit outputs a control signal to control the conversion unit according to the duty cycle reference signal and feedback signal, thereby limiting the output power of the power output module within the maximum power region. A tracking method of the maximum power is also disclosed.

Abstract: A power supplying device having programmable current-balancing control includes at least two power modules in parallel. Each power module includes a power convertor, a current sensing component, a tuning circuit, a current-balancing control circuit and an output voltage controller. The power convertor provides power to a load via an output end. The current sensing component senses output current of the power convertor to generate a current sensing signal. The tuning circuit generates a tuning signal according to a control signaling from a communicating port. The current-balancing control circuit receives the current sensing signal and the tuning signal. The current-balancing control circuit generates a current-balancing signal according to the current sensing signal. The current-balancing control circuit generates a voltage control signal according to the tuning signal.

Abstract: An apparatus, system and method are described that enable an impedance of a plasma load to be matched with a power generator. In some embodiments the apparatus includes a power output adapted to apply power that is utilized to energize a plasma; a sensor adapted to sample power applied at the power output so as to obtain power samples; and an impedance control output configured to provide, responsive to the power samples, an impedance-control signal that enables an impedance matching network connected to the output of the power generator and to the impedance control output to match, responsive to the an impedance-control signal, the impedance of the plasma to the operating impedance of the power generator.

Abstract: A regulator includes a transistor connected between an input and an output. A feedback voltage controls the transistor to keep the output voltage constant. A first circuit functions as a comparator to compare a detection voltage from the output of the transistor and the feedback voltage when the output current is higher than a predetermined value, and functions as a buffer when the output current is lower than the predetermined value. A second circuit receives a reference voltage, the feedback voltage, and an output from the first circuit, and generates (i) a difference between the feedback voltage and the first circuit output when the reference voltage is lower than the first circuit output, and (ii) a difference voltage between the feedback voltage and the reference voltage when the reference voltage is higher than the first circuit output, and supplies a control voltage to control the output of the transistor.

Abstract: According to one embodiment, the power circuit includes a first feedback loop which feedbacks information on an output voltage and a second feedback loop which feedbacks information on a load current. When the load current is smaller than a predetermined threshold value, the second feedback loop is blocked and a PWM signal is generated using data of a feedback current signal which is stored before blocking the second feedback loop.

Abstract: A power factor corrected switched mode power supply including a phase shifter that senses the mains frequency and phase shifts it to produce a phase shifted signal which modulates the switching signal supplied to the switches based on the phase shifted signal. The rate of change of the frequency of the switching signal may be controlled to be greatest in regions of greatest power transfer.

Abstract: The regulated output voltage of a voltage regulator is maintained up to a current limit, Ilimit, then as the load impedance continues to decrease the output current does not increase past the current limit, Ilimit, but rather the output voltage decreases forcing the output current to also decrease to satisfy Ohm's Law: IOUT=VOUT/ZLoad. When the output voltage drops below the regulated voltage value because of current limiting the voltage regulator shifts from a current limit mode to a current foldback mode wherein the output current decreases with the decrease in output voltage until the output current reaches a current foldback minimum, Ifoldback, at an output voltage of substantially zero volts. As the load impedance increases so will the output voltage and current until the output voltage is back at substantially the regulation voltage value, and the output current is less than or equal to the current limit, Ilimit.

Abstract: An average current mode buck-boost DC to DC converter has a buck stage coupled between an input voltage source terminal and an output terminal. A boost stage is coupled between the input voltage source terminal and the output terminal. A current ramp control circuit generates a ramp signal for driving the buck and boost stages, the ramp signals being coupled to the buck and boost stages. A constant voltage related to the desired output voltage by a constant is applied directly to both a voltage control feedback loop for adjusting the output voltage and directly to an input to the current ramp control circuit, whereby the output voltage can be shifted from one voltage to another by feedforward control.

Abstract: A controller having an on-time controller, an off-time controller, a switch control signal generator, and a jittering signal generator, wherein the jittering signal generator couples jitter into the on-time or the off-time of a primary switch of the power supply. Therefore the EMI performance may be improved.

Abstract: In one aspect, this disclosure relates to a method of controlling current output from a switching regulator to a load via an inductor. Inductor current information can be sampled at a peak level, such as just before a transistor configured to cause current to flow through the inductor is turned off. The sampled inductor current can be compared with a reference current, and a current limit threshold can be adjusted based on the comparison. The output current of the switching regulator can be controlled based on a comparison of the current limit threshold with an indicator of current flowing through the inductor. This method can accurately and efficiently limit current in a switching regulator.

Abstract: A system includes an estimation module and a current measuring module. The estimation module estimates current through an inductor in an output stage of a power supply using a model of the current and generates an estimated current. The current measuring module measures the current through the inductor and generates a measured current. The estimation module adjusts the model based on the measured current.

Abstract: The disclosure provides a power factor correcting (PFC) circuit, a power supply and a method of manufacturing a power converter. In one embodiment, the PFC circuit has a positive input terminal, an output terminal and a ground terminal and includes: (1) a power factor inductor coupled in series between the positive input terminal and the output terminal, (2) a main switch configured to periodically connect the power factor inductor to the ground terminal and (3) a clamping capacitor coupled to the power factor inductor and configured to provide zero turn-off loss for the main switch.

Abstract: DC to DC converters are described that include two converters interconnected and operated to mitigate at least some of the effects of low duty cycle operation.

Abstract: Electronic devices may have batteries that power internal circuitry. A power converter may connect to an input-output port in an electronic device to deliver power to the electronic device. Battery charging circuitry in the electronic device may be used to charge the battery in an electronic device while power is delivered from the power converter. The power converter may have load detection circuitry. When an output load is present, the power converter operates in an active mode and delivers power to the electronic device. When the output load is not present, the power converter enters a low-power standby mode. The electronic device has switching circuitry that periodically either electrically couples or electrically isolates the input-output port from internal circuitry. When the input-output port is isolated, the power converter senses that no output load is present and enters the standby state to conserve power.

Abstract: A power converter provides current limit/current share functionality, allowing use in a point-of-load architecture and/or in parallel with one or more other power converters. An inner current control loop may sense output current over only a portion of a duty cycle, for example at a low side active switch. The resulting signal is compensated, and may be level shifted, for example via a resistor divider network, and supplied to a current control amplifier. An outer voltage control loop may sense output voltage, and provide a voltage error signal from a voltage error amplifier to the resistor divider network. Power converters are operable as masters or slaves, and include sense input and trim input terminals.

Abstract: A negative current protection system for a low side switching converter FET, for use with a switching converter arranged to operate high and low side FETs connected to an output inductor to produce an output voltage. The negative current protection system comprises a current sensing circuit which produces an output Vcs that varies with the current in the high side FET, a negative current threshold generator which produces a threshold signal ?Ith which represents the maximum negative current to which the low side FET is to be subjected, and a comparison circuit arranged to compare the valley portion of Vcs and ?Ith and to set a flag if Vcs<?Ith at a predetermined time in the switching cycle—typically after the converter's blanking time. When the flag is set, the system preferably responds by adjusting the operation of the switching FETs to reduce the negative current.

Abstract: A system for controlling load current in a voltage converter includes a current normalization module that receives a first measurement corresponding to the load current, receives a second measurement corresponding to an inductor current, and matches a first gain of the first measurement corresponding to the load current to a second gain of the second measurement corresponding to the inductor current to generate a normalized load current. A feed-forward generation module receives the normalized load current from the current normalization module and generates a load current feed-forward (LCFF) signal based on the normalized load current. A duty cycle generation module generates a duty cycle used to control the voltage converter based on a commanded output voltage of the voltage converter and the LCFF signal.

Abstract: A buck converter configured for converting a voltage output from a power supply to a load includes a first switch, a second switch, an inductor, three compensators and a control microchip. The first switch and the second switch are connected in series between two ends of the power supply. A first end of the inductor is connected to a node between the first switch and the second switch; a second end of the inductor serves as an output terminal connected to the load. The compensators are correspondingly connected to the first switch, the second switch and the inductor. The control microchip is electrically connected to the first and second switches and the node. The control microchip controls the first and second switches to turn on or off, and executes a current protective process when output current of the output terminal exceeds a current protective threshold of the load.

Abstract: A controller and controlling method is disclosed for a boost converter. The controller includes a first node for receiving an output sense signal indicative of an output DC voltage, a second node for receiving a boost current sense signal indicative of current through an inductor of the boost converter, a first combiner which provides an error signal based on a difference between the output sense signal and a reference signal, an integrator which integrates the error signal and which provides a compensation signal indicative thereof, and a pulse controller which provides a pulse control signal for controlling the power switch to operate the boost converter in DCM. The pulse controller develops pulse control signal based on comparing the compensation signal with a ramp signal and further adjusts the pulse control signal over a cycle of a rectified AC input voltage based on the boost current sense signal.

Abstract: In a current mode controlled switching power supply, current through the inductor is sensed to determine when to turn off or on the switching transistors. The inductor current has a higher frequency AC component and a lower frequency DC component. The AC current feedback path, sensing the ramping ripple current, is separate from the DC current path, sensing the lower frequency average current. Separating the current sensing paths allows the signal to noise ratio of the AC sense signal to be increased and allows the switching noise to be filtered from the DC sense signal. The gain of the DC sense signal is adjusted so that the DC sense signal has the proper proportion to the AC sense signal. The AC sense signal and the DC sense signal are combined by a summing circuit. The composite sense signal is applied to a PWM comparator to control the duty cycle of the switch.

Abstract: A power amplifying circuit includes a first field effect transistor and a second field effect transistor that are connected in series, are interposed between a high potential power line and a low potential power line, and drive a load; a predriver that generates, in response to an input signal, gate voltages applied to the first field effect transistor and the second field effect transistor respectively; and a variable power source that supplies source voltages to the high potential power line and the low potential power line respectively, and is configured to control the source voltages.

Abstract: In an embodiment, an apparatus includes a charging circuit and a determining circuit. The charging circuit is configured to generate a charge on a capacitor with a first current that is related to a signal having a characteristic, and the determining circuit is configured to determine the characteristic of the signal in response to the charge on the capacitor. For example, such an apparatus can determine an average of an input current to a power supply, or an average of an output current from a power source for the power supply, by mirroring the input current, charging a capacitor with the mirroring current, and determining the voltage across the charged capacitor.

Abstract: In an embodiment, an apparatus includes a charging circuit and a determining circuit. The charging circuit is configured to generate a charge on a capacitor with a first current that is related to a signal having a characteristic, and the determining circuit is configured to determine the characteristic of the signal in response to the charge on the capacitor. For example, such an apparatus can determine an average of an input current to a power supply, or an average of an output current from a power source for the power supply, by mirroring the input current, charging a capacitor with the mirroring current, and determining the voltage across the charged capacitor.