Abstract: A supply voltage detecting circuit has a voltage detection circuit and a current clamping circuit. The voltage detection circuit receives and detects a supply voltage and is used to detect to generate a low-voltage detection signal. When the supply voltage is lower than a set level, the low voltage detection signal output by the voltage detection circuit turns off the current clamping circuit, and a transistor current flowing through the voltage detection circuit is proportional to the supply voltage; and when the supply voltage is higher than or equal to the set level, the low voltage detection signal output by the voltage detection circuit turns on the current clamping circuit, and the current clamping circuit provides a constant current to maintain the operation of the voltage detection circuit, wherein the transistor current flowing through the voltage detection circuit is proportional to the constant current.

Abstract: A sensor device comprises a sensor arranged to sense and convert the physical quantity into an electrical quantity and to output an electrical signal representative of the electrical quantity. A voltage limiter receives an input signal related to a supply voltage providing power to the sensor device and to output a voltage signal. The voltage signal has a limited value if the input voltage exceeds a voltage saturation threshold value. A voltage-to-current converter converts the voltage signal output by the voltage limiter to a supply current of a first value, thereby forming a first supply current state. A switch switches between the first supply current state and at least a second supply current state wherein the supply current is substantially independent of the supply voltage. Current generation means provides the supply current of the predetermined second value to form the second supply current state.

Abstract: In an example, an apparatus includes a level-shifting circuit and a ramp detector. The level-shifting circuit has a current choke and a transistor coupled across the current choke, the level-shifting circuit adapted to be coupled to a first voltage source. The ramp detector has a ramp detector input adapted to be coupled to the first voltage source and a ramp detector output coupled to the transistor, the ramp detector adapted to be coupled to a second voltage source.

Abstract: Example apparatus, systems, and methods receive, by a current digital-to-analog converter (DAC) of a shunt regulator, a first digital code indicative of a first programmable power supply command specifying a first programmable output voltage (Vbus) to be delivered to a voltage bus of a USB-compatible device. The programmable power supply command is compatible with a universal serial bus—power delivery (USB-PD) standard. Responsive to receipt of the first digital code, adjust, by the current DAC, a sink current delivered to a feedback node to adjust an output voltage to the first Vbus for dynamic programmability. The feedback node is coupled to a first input of an amplifier of the shunt regulator and the first Vbus is programmable.

Abstract: An interface circuit serves to receive an input signal VIN having a high level defined as a high potential VIH and a low level defined as a low potential VIL, and output an output signal VOUT having a high level defined as a high potential VOH and a low level defined as a low potential VOL. The interface circuit includes a polarity controller configured to control the output signal VOUT to be in phase in level with the input signal VIN or to be reversed in polarity with respect to the input signal VIN, depending on whether the high potential VIH or the low potential VIL is a GND potential.

Abstract: A voltage conversion device can smoothly switch between a state of performing voltage control and a state of performing current control while maintaining the stability of operation of a voltage conversion unit. A control unit (10) of the voltage conversion device (1) selectively switches the control mode of the voltage conversion unit (3) to a current control mode or a voltage control mode and performs a control process of each control mode. In the voltage control mode, the control unit (10) determines a target current for voltage control according to a voltage deviation and performs the same feedback control process as the current control mode by using the target current to control the voltage conversion unit.

Abstract: A power supply system (101) includes a first power supply apparatus (111a) and a second power supply apparatus (111b) connected to a load in parallel, for supplying power to the load (115). The first supply apparatus (111a) includes a first controller that controls the output voltage of the first supply apparatus (111a) when a power supply from the first supply apparatus (111a) to the load 115 is equal to or greater than a power requirement by the load (115), and controls the output current of the first supply apparatus (111a) when the supplied power is less than the required power. The second power supply apparatus 111b includes a second controller that stops the second supply apparatus from supplying power (111b) when the power supply is equal to or greater than the power requirement, and controls the output voltage of the power supply apparatus (111b) when the power supply is less than the power requirement.

Abstract: A voltage converter system includes a first DC-AC voltage converter that converts a first DC voltage signal to a first AC voltage signal. A DC link converts the first AC voltage signal to a second DC voltage signal. A second DC-AC voltage converter converts the second DC voltage signal to a second AC voltage signal. In another configuration a DC-AC voltage converter converts a DC voltage signal to a first AC voltage signal. An AC-AC voltage converter converts the first AC voltage signal to a second, lower-frequency AC voltage signal. In yet another configuration a first voltage converter portion converts a DC voltage signal to pulses of DC voltage. A second voltage converter portion converts the pulses of DC voltage to a relatively low-frequency AC voltage signal. The voltage converter system is selectably configurable as a DC-AC voltage converter or an AC-DC voltage converter.

Abstract: According to one aspect, embodiments herein provide a flyback converter comprising an input, an output, a rectifier, a transformer having a primary winding and a secondary winding, a switch, the switch being closed in a first mode of operation and open in a second and third mode of operation, and a regenerative snubber circuit, wherein the flyback converter is configured such that in the first mode of operation, the DC power from the rectifier charges the transformer, wherein the flyback converter is configured such that, in the second mode of operation, the snubber circuit is configured to store leakage energy from the primary winding, and wherein the flyback converter is configured such that, in the third mode of operation, the snubber circuit is configured to provide the stored energy to the primary winding. The flyback converter may also have high power factor at the input while operating from AC input.

Abstract: Source measure units may operate as a voltage/current (V/I) source for a load, such as a device under test (DUT). Source measure units having a voltage controlled mode and a current controlled mode are described. The source measure units may have a suitable configuration to transition between the voltage controlled mode and current controlled mode in a smooth manner, and may be operated accordingly.

Abstract: One embodiment of the present disclosure provides a method for controlling a power switch that includes converting a control signal to a current pulse signal, where the control signal is referenced to a first reference potential. The method also includes generating a switch drive voltage signal based on the current pulse signal, where the switch drive signal is referenced to a second reference potential. The method also includes controlling the conduction state of a power switch using the switch drive voltage.

Abstract: A converting circuit for receiving an input voltage and generating an output current, including: a transistor, coupled to a supply voltage at a drain of the transistor, and a source of the transistor is coupled to a first voltage, and a gate of the transistor is coupled to the input voltage and a fixed voltage; and a resistor, coupled to the input voltage and the gate of the transistor, and the output current flows through the resistor, wherein the output current is related to the fixed voltage, the input voltage and the resistor.

Abstract: The present disclosure relates generally to a light emitting diode (LED) luminaire. In one embodiment, the LED luminaire includes a base, a heat sink coupled to the base, a power supply coupled to an interior volume of the heat sink, one or more LEDs coupled to the power supply, wherein the one or more LEDs are coupled to a circuit configured to provide a constant input impedance and a lens coupled to the heat sink and enclosing the one or more LEDs.

Abstract: Provided is a voltage reference circuit which is able to obtain high PSRR without a variation in power-supply voltage and an influence of noise. A voltage reference circuit for performing voltage-current conversion on forward voltages of PN junction elements and on a difference therebetween to generate a voltage so as not to depend on a temperature is constituted by an amplifier for controlling a temperature characteristic of a voltage of an output terminal, a source follower circuit for supplying a power to the amplifier, and a PMOS transistor which is controlled by the amplifier and which controls a current to flow into the PN junction elements.

Abstract: A differential current signal circuit is described which includes a voltage to differential current converter circuit that generates a differential pair of current output signals in response to receiving a voltage input signal, where the differential pair of current output signals are linearly proportional to the voltage input signal within a voltage operating range from a minimum operating voltage to a maximum operating voltage. The differential pair of current output signals are linear over a wide range of voltage input signals. A correction circuit is included which eliminates voltage offsets in the voltage operating range due to process and temperature variations. The correction circuit also provides the capability to adjust the minimum operating voltage, and eliminates variations in the minimum operating voltage due to process and temperature variations.

Abstract: A compensation circuit and method for constant current regulation of switching mode power supply are disclosed. The ringing waveform of a feedback signal, indicative of the output current of the power supply, causes error. To eliminate the error, a current source charges a capacitor in response to a demagnetizing oscillation signal indicative of the error caused by the ringing waveform of the feedback signal. The voltage across the capacitor is compared to a reference signal to generate a more accurate signal indicative of the conductive time of a secondary diode in a secondary winding of the switching mode power supply. This more accurate signal is inputted to a logic circuit to generate a constant current control signal to control a power switch of the power supply.

Abstract: A voltage source converter station including a multilevel voltage source converter, for conversion of electrical power between AC and DC, and a control system. The voltage source converter includes a plurality of switching cells including switchable semiconductors, and the control system includes at least one main control unit for providing a voltage reference signal and a plurality of cell control units. Each cell control unit uses carrier based pulse width modulation for controlling the switching of a respective cell, where the main control unit is communicatively connected to the cell control units and provides the reference voltage signal to each cell control unit and each cell control unit creates a switching signal to each respective switching cell using the reference voltage signal and a carrier signal to effectuate the conversion.

Abstract: An emergency power system for operation during loss of power on power mains comprises a spring-driven energy storage unit (ESU) and a generator. The ESU enters a generator mode responsive to a power outage state of a power sensor, during which mode unwinding of the spring drive powers the generator. After power is restored to the mains, a preferred embodiment automatically rewinds the spring using the generator as a motor.

Abstract: A differential current signal circuit is described which includes a voltage to differential current converter circuit that generates a differential pair of current output signals in response to receiving a voltage input signal, where the differential pair of current output signals are linearly proportional to the voltage input signal within a voltage operating range from a minimum operating voltage to a maximum operating voltage. The differential pair of current output signals are linear over a wide range of voltage input signals. A correction circuit is included which eliminates voltage offsets in the voltage operating range due to process and temperature variations. The correction circuit also provides the capability to adjust the minimum operating voltage, and eliminates variations in the minimum operating voltage due to process and temperature variations.

Abstract: An interleaved flyback converter device with leakage energy recycling includes: two flyback converters and an input power. Each flyback converter includes a capacitor, a switch, two diodes, and a transformer. The input power is connected to the capacitors of the two flyback converters respectively. By using the capacitors as input voltage, the two flyback converters are provided with lower voltage rating. The diodes are used to recycle leakage energy directly, and to clamp voltage on power components. Therefore, in addition to enhancing efficiency via recycling leakage energy, the two flyback converters have lower switching losses due to lower switching voltage.

Abstract: Power extracted from an antenna inductively coupled to an alternating magnetic field is regulated to provide voltage supplies. In some implementations, a first voltage supply (e.g., 3.8 volts) provides regulated voltage to analog circuits and a second, lower, voltage supply (e.g., 1.4 volts) provides regulated voltage to digital circuits. The first voltage supply is regulated, using shunt regulation, by a first voltage regulator circuit. The second voltage supply is regulated, using a series regulation, by a second voltage regulator circuit. The second voltage regulator circuit is supplied by the shunted current from the first voltage regulator. Excess shunt current provided by the first regulator circuit can be bypassed (e.g., bypassed to ground). The second voltage regulator circuit can use a timer circuit to control the amount of charge transferred to a second voltage supply rail. The timer circuit can compensate for different currents from the first voltage regulator circuit.

Abstract: A power supply circuit having a converter circuit and method for determining a current flowing into the converter circuit. A converter circuit includes an amplifier and a current-to-current converter module. The amplifier has a current sensing element coupled between its inverting and noninverting input terminals. The amplifier generates a sensing signal from a charging current flowing through the current sensing element. The sensing signal is input into the current-to-current converter module, which scales the charging current and modulates the scaled charging current. The current-to-current converter module converts the modulated current to a charging voltage that is representative of the charging current. The charging current is converted to a current that is representative of the input current to converter circuit. The input current to the converter circuit is added to an auxiliary load current to yield the current of the power supply circuit.

Abstract: In order for keeping the amplitude of the excitation current of a vibrator constant irrespective not only of the temperature variation but also of the manufacturing variation and the variation in frequency, a comparison control circuit for controlling the amplitude of the drive signal for exciting the vibrator includes a comparative voltage supply circuit for supplying the comparative voltage, and the comparative voltage supply circuit generates the comparative voltage with a constant current source and a second resistor made of a material the same as a material of a first resistor included in a current-voltage conversion circuit.

Abstract: The present invention aims to enhance the reliability of a semiconductor device having first through fourth capacitive elements. The first through fourth capacitive elements are disposed over a semiconductor substrate. A series circuit of the first and second capacitive elements and a series circuit of the third and fourth capacitive elements are coupled in parallel between first and second potentials. Lower electrodes of the first and third capacitive elements are respectively formed by a common conductor pattern and coupled to the first potential. Lower electrodes of the second and fourth capacitive elements are respectively formed by a conductor pattern of the same layer as the above conductor pattern and coupled to the second potential. Upper electrodes of the first and second capacitive elements are respectively formed by a common conductor pattern and brought to a floating potential.

Abstract: A power adaptor detection system includes a power adaptor device configured to receive electrical power at a first voltage and to convert the electrical power to a second voltage. The second voltage has a lower value than the first voltage. An identification generating circuit is coupled to the power adaptor device. The identification generating circuit is configured to convert a portion of the electrical power to a substantially constant value electrical current. An identification detection circuit is configured to detect the second voltage. Detecting the second voltage causes the identification circuit to determine the value of a pulse of the electrical current, wherein the value of the electrical current is an identification attribute of the power adaptor device.

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

Abstract: Power extracted from an antenna inductively coupled to an alternating magnetic field is regulated to provide voltage supplies. In some implementations, a first voltage supply (e.g., 3.8 volts) provides regulated voltage to analog circuits and a second, lower, voltage supply (e.g., 1.4 volts) provides regulated voltage to digital circuits. The first voltage supply is regulated, using shunt regulation, by a first voltage regulator circuit. The second voltage supply is regulated, using a series regulation, by a second voltage regulator circuit. The second voltage regulator circuit is supplied by the shunted current from the first voltage regulator. Excess shunt current provided by the first regulator circuit can be bypassed (e.g., bypassed to ground). The second voltage regulator circuit can use a timer circuit to control the amount of charge transferred to a second voltage supply rail. The timer circuit can compensate for different currents from the first voltage regulator circuit.

Abstract: The present invention provides a direct current generator and a pulse generator thereof. The pulse generator includes a comparator to replace a central processing unit and a logic integrated circuit to save the costs and space required by the electronic components. The pulse generator generates pulses to control the activation of the direct current generator and then to control the output current of the direct current generator. The direct current generator generates current having pulses based on pulses signals from the pulse generator to drive a load.

Abstract: A power supply device, particularly for an airplane, has a control unit that is provided to match a current path to a voltage curve. An embodiment relates to a rectifier with power factor correction in the form of a step-up converter with switchable (startup) current limitation.

Abstract: A circuit for detecting overcurrent flowing to an output transistor. A replica transistor generates a reference voltage that is in accordance with a reference current flowing from a constant current circuit. A voltage-current conversion circuit generates a determination reference current proportional to the reference current based on the reference voltage. A current-voltage conversion circuit converts the determination reference current to a determination reference voltage. A detector detects overcurrent flowing to the output transistor based on the determination reference voltage.

Abstract: A semiconductor integrated circuit includes: a power supply circuit; a voltage-current conversion circuit connected with an output of the power supply circuit, the voltage-current conversion circuit having an output terminal; a current-voltage conversion circuit connected with the output terminal of the voltage-current conversion circuit, the current-voltage conversion circuit having an output terminal; a constant-voltage line connected with the output terminal of the current-voltage conversion circuit; an output circuit which has an output terminal to which an external element is connected at a rear stage thereof; and a protection circuit which receives a potential of the constant-voltage line and the output signal from the power supply circuit to control a potential of the output terminal, and prevents the external element from operating when an increase in the potential of the constant-voltage line is insufficient or the power supply voltage is not in a steady state.

Abstract: A power supply control method is adapted to a current-to-voltage conversion circuit which has a transformer for converting and outputting an input power. The power supply control method stops a power supply to the transformer when an output side of the current-to-voltage conversion circuit is in a no-load state, and starts a power supply to the transformer when an external voltage is applied to the output side of the current-to-voltage conversion circuit.

Abstract: In one embodiment, a start-up controller for a PWM power supply controller is formed to generate a current that is substantially constant for changes in temperature and for changes in an output voltage received by the start-up controller.

Abstract: An electrical energy generation system comprising: a plurality of photovoltaic generators connected in parallel and connected to a common load via respective DC voltage converters; and a regulator configured to vary the transconductances of said respective voltage converters to maximize the power generated by said current generators; wherein: said generators are also connected to a common input of an additional voltage converter the output of which is connected to said common load; and said regulator is also configured to vary the transconductance of said additional voltage converter to maximize the power generated by said current generators.

Abstract: A system for measuring performance of a voltage regulator module (VRM) attached to a microprocessor includes: a voltage transient tester (VTT) fixture (5) for setting different working voltage levels of the VRM; an oscillograph (2) for measuring transient voltage levels of the VRM, and generating a transient voltage waveform according to the transient voltage levels; an voltmeter (3) for measuring steady voltage levels of the VRM under thermal effects generated by the microprocessor; a direct current (DC) electronic load (4) for educing load currents from the VRM; and a measurement control module (10) installed in a computer (1) for generating load current control signals, controlling the DC electronic load to educe the load currents from the VRM according to the load current control signals, and generating a performance report of the VRM by integrating various measurement results.

Abstract: A photocurrent sensing circuit includes a logarithmic compression circuit; a cancellation circuit logarithmically compressing a current substantially equal in temperature coefficient of the photocurrent to convert the same into a voltage, and performing an addition or a subtraction on the converted voltage and a voltage converted from a photocurrent by logarithmically compression; a logarithmic operation circuit logarithmically compressing the voltage received from the cancellation circuit to produce a first voltage, logarithmically compressing a voltage proportional to a thermal voltage of the photocurrent to produce a second voltage, logarithmically compressing a current having thermal dependence of nearly zero to produce a third voltage and performing an addition or a subtraction of each of the second and third voltages with respect to the first voltage to produce a fourth voltage; and an inverse logarithmic transformation circuit performing inverse logarithmic transformation on the fourth voltage to outpu

Abstract: An inverter has a semiconductor switch circuit in the primary winding of a transformer such that each of the switches of the switch circuit is controlled by pulse-width modulation (PWM) to supply a constant ac current and a constant ac voltage to a load, such as a cold cathode fluorescent light, connected to a secondary winding of the transformer. A common slow-start control circuit is provided in the inverter circuit to enable a common slow startup of the PWM control of the output voltage and output current. This arrangement suppresses an excessive voltage and an inrushing current during a startup.

Abstract: A current/charge-voltage converter having an operational amplifier and a first capacitor connected between the input terminal and the output terminal of the operational amplifier, comprising a first switch which has one end connected to this input terminal, a first signal source that generates control signals for the first switch, a second capacitor connected to the first capacitor, and a second signal source connected to the other terminal of the second capacitor.

Abstract: An analog level shifter includes a voltage output circuit which generates a first voltage and a second voltage in response to an input voltage and which adds the second voltage to the first voltage to output a third voltage, a voltage-current converting circuit to which the third voltage is inputted and which outputs a converted current proportional to the third voltage, a current subtracting circuit which subtracts a desired current from the converted current outputted by the voltage-current converting circuit, to output the resulting current, and a current-voltage converting circuit which generated a fourth voltage proportional to the current outputted by the current subtracting circuit.

Abstract: Method for controlling an output signal (A) of a voltage-current converting device, to which a reference voltage (UREF) is fed and in which a voltage signal (I, IX) applied on the input side is converted into a current signal, a reference voltage (UREF) setting the output quiescent current (I0). The provision of a setting device, which is connected to the reference input and is used to determine an envelope of an amplitude-modulated signal at the input is furthermore expedient.

Abstract: A current/charge-voltage convert circuit having an operational amplifier and a capacitor connected between the input terminal and the output terminal of the operational amplifier, this current/charge-voltage convert circuit characterized in that it comprises a first pair of diodes connected in mutually opposing directions to this input terminal, a second pair of diodes connected in the opposite direction of this first pair of diodes to the respective other terminal of this first pair of diodes, a pair of current sources connected in mutually opposing directions to the respective other terminal of this first pair of diodes, a pair of switches connected to the respective other terminal of this first pair of diodes, and resistors connected between the respective other terminal of this second pair of diodes.

Abstract: A voltage controlled oscillator (600) includes a voltage to current portion (400) that is inversely proportional to the semiconductor processing in order to compensate for variations both in the low-frequency and high-frequency portions of the VCO gain response. To compensate for low-frequency variations, a portion of the control current (ICTL), non-compensated control current ICTLNC (436), is subtracted from a reference current IREF (408) and the result, a low-frequency compensating control current, ICTLLF (438), is added to the non-compensated control current ICTLNC (436). To compensate for high frequency variations, a number of differential transistor pairs (410-416) are provided that have tail currents that are inversely proportional to the processing. One input (426) to all the differential pairs is connected to the VCO's control voltage while the other inputs (418-424) are connected to successively increasing voltages in the control voltage range.

Abstract: An improved voltage to current converter circuit having three stages. The first stage amplifies the input voltage signals. The second stage includes first and second/third current sources that are connected in a current mirror configuration with a common node therebetween. The third stage consists of an output transistor to form a half cascode current mirror having its drain connected to the second/third current sources and to the output terminal. The gate of the output transistor is coupled to a bias voltage and to the drain of an additional transistor so that the potential on the gate of the output transistor can vary to have both transistors of the third stage in the saturation state for a wide range of the current flowing through the transistors of the half cascode current mirror.

Abstract: A power supply control method is adapted to a current-to-voltage conversion circuit which has a transformer for converting and outputting an input power. The power supply control method stops a power supply to the transformer when an output side of the current-to-voltage conversion circuit is in a no-load state, and starts a power supply to the transformer when an external voltage is applied to the output side of the current-to-voltage conversion circuit.

Abstract: A shunt-shunt feedback current to voltage converter (60) including a compensating current (22) provided to the output of the amplifier (12) which mirrors the input current (14) advantageously removing the loading effects of the feedback resistor (Rƒ) to the amplifier (12). A current steering DAC (40) is utilized in conjunction with a plurality of polarity control switches (62) to provide either a source current or a sink current to the amplifier input, and a complementary sink current or source current, respectively, to the output of the amplifier such that the amplifier (12) does not provide any current to the feedback resistor. Thus, DC gain of the amplifier is maintained. The current steering DAC (40) provides a matched source current and sink current to achieve this architecture.

Abstract: A method and apparatus provide for accurate low current generation using switched capacitor techniques. The current generator includes a reference voltage generator that provides a reference signal to a switched capacitor integrator. In one example, the reference circuit includes a switched capacitor divider. The switched capacitor integrator circuit produces a voltage ramp in response to the reference signal and other timing signals. The rate of the voltage ramp is proportional to the ratio of capacitors in the switched capacitor integrator and a clock frequency that is associated with the timing signals. A feedback circuit impresses the voltage ramp across an output capacitor circuit that has a very low capacitance value. The capacitor is arranged to differentiate the voltage ramp to produce an accurate low current. The switched capacitor design is suitable for integration in a monolithic integrated circuit. The integrator and the feedback stage are periodically reset.

Abstract: A method and apparatus is provided for converting a voltage signal into a current signal. A differential circuit is used to convert a voltage signal into a current signal. The differential circuit comprises at least one feedback amplifier to reduce non-linearity in the differential circuit.

Abstract: There is intended to provide a current-voltage converter capable of surely outputting a voltage output signal regardless of current intensity when converting a current input signal with wide current range into a voltage output signal. In case a current value of a current input signal Iin is small, small current regions of diodes D10 1 and D102 are used and current values of first bias currents IB1 and IB2 are set small. Thereby, the small current regions can be used as a region to deal with a large change rate of voltage against current and there can be obtained an effective voltage change even for a micro current. In case a current value of the current input signal Iin is large, current values of bias currents IB1 and IB2 at a constant current circuit 13 increase to a second bias current to obtain a characteristic such that conversion voltage VM and reference voltage VP are compressed against the current input signal Iin.

Abstract: A reverse level shift circuit that is low in cost and excellent in reliability is provided by employing no Pch-DMOS transistor and forming it together with a level shift circuit on one semiconductor substrate. An input voltage signal (VIN) on high side is converted to a current signal by a voltage-current conversion circuit (CV1) and a current source (CS1). Using a Nch-DMOS transistor (ND1) of common gate construction as a high breakdown voltage resistance, the current signal is then transferred to low side, on which the current signal is converted to a voltage signal by a current source (CS2) and a current-voltage conversion circuit (CV2). Thereby, the signal change of the signal (VIN) using potential (HGND) as a reference potential can be outputted as a signal change of signal (VOUT) that uses potential (GND) as a reference potential.

Abstract: There is intended to provide a current-voltage converter capable of surely outputting a voltage output signal regardless of current intensity when converting a current input signal with wide current range into a voltage output signal. In case a current value of a current input signal Iin is small, small current regions of diodes D101 and D102 are used and current values of first bias currents IB1 and IB2 are set small. Thereby, the small current regions can be used as a region to deal with a large change rate of voltage against current and there can be obtained an effective voltage change even for a micro current. In case a current value of the current input signal Iin is large, current values of bias currents IB1 and IB2 at a constant current circuit 13 increase to a second bias current to obtain a characteristic such that conversion voltage VM and reference voltage VP are compressed against the current input signal Iin.

Abstract: Disclosed is a conventional safety razor having a sounding board disposed immediately behind and approximately coextensive and even with the razor head, the sounding board being in the form of a thin plastic plate extending upwardly from the razor handle, with the plate serving as both a means for scraping hair stubble on human skin, as well as a means for audibly amplifying vibrations induced thereby. This alerts the user to the continued presence of objectionable hair stubble so that the shaving process is repeated with or without a change of safety razors or razor blades as required. Alternatively, a miniature solid-state microphone may be mounted on the safety razor for sensing the vibrations and driving an audio speaker through an amplifier/filter network.