Abstract: A drive device drives a motor serving as a load. A first upstream switch is disposed upstream from the motor and a first downstream switch is disposed downstream from the motor in a first current path of current flowing via the motor. A second upstream switch is disposed upstream from the motor and a second downstream switch is disposed downstream from the motor in a second current path of current flowing via the motor. A direction of the current flowing in the motor when current flows in the first current path is different from a direction of the current flowing in the motor when current flows in the second current path. The first upstream drive circuit stops flow of current via the first upstream switch when the current flowing through the first upstream switch becomes greater than or equal to a current threshold.

Abstract: A memory device includes a first memory block. The first memory block includes a first memory sub-array and a first interface portion disposed next to the first memory sub-array. The first memory block further includes a plurality of first interconnect structures electrically coupled to the first memory sub-array through the first interface portion, and a second plurality of interconnect structures configured to electrically couple a corresponding one of the plurality of first interconnect structures to a transistor. The memory device further includes a first test structure and a second test structure disposed next to the first memory block, each configured to simulate electrical connections of the plurality of second interconnect structures. The first and second test structures are electrically coupled to each other and are each electrically isolated form the first memory block.

Abstract: A gate drive device drives a gate of a semiconductor switching element and controls a transient voltage corresponding to a voltage of a main terminal of the semiconductor switching element to a target value of the transient voltage at a time of switching the semiconductor switching element. The gate drive device includes a calculation circuit, a drive circuit, a detection circuit, and a learning circuit. The calculation circuit executes a predetermined calculation mode to calculate an operation amount for operating gate drive speed of the semiconductor switching element. The drive circuit drives the gate of the semiconductor switching element according to the operation amount. The detection circuit detects the transient voltage. The learning circuit executes learning processing to change the predetermined calculation mode based on the operation amount calculated by the calculation circuit and the transient voltage detected by the detection circuit.

Abstract: The circuit breaker control module of the present disclosure comprises: a plurality of semiconductor switching units for blocking current flows of transmission distribution lines or performing switching operations so as to switch the current flow directions; a control unit for controlling the turn-on/turn-off operation of each semiconductor switching unit by transmitting a trip signal to each of the plurality of semiconductor switching units; and a plurality of insulation type signal transmission element units which are provided between the plurality of semiconductor switching units and the control unit such that the semiconductor switching units and the control unit are insulated, and which transmit the trip signal from the control unit to each of the plurality of semiconductor switching units, and thus the presently disclosed circuit breaker control module can reduce the risk of accidents due to an electrical arc and increase the stability and reliability of the control unit.

Abstract: According to an aspect of this disclosure, an intrinsically safe circuit includes a voltage source, a Zener diode, a transistor, a switching element, one or more resistors, and a current limiting stage. According to this aspect, the intrinsically safe circuit may be configured such that an over-voltage threshold is determined by a voltage across the Zener diode, a base-emitter voltage of the transistor, and a voltage across the one or more resistors.

Abstract: The present application provides a power device driver including a detection module coupled to the power device and configured to detect the state of the power device; a driving module coupled to the detection module and the power device respectively and configured to detect the power of the detection module. As a result, the power device is regulated; wherein the detection module includes a fast detection sub-module configured to detect a state of the power device within a preset time period after the input signal of the driving device is invalid, and controlling the driving module to softly turn off the power device when there is overcurrent. The present application also provides a corresponding power device driving method and electric equipment.

Abstract: Circuits for providing overcurrent protection are disclosed herein. The circuits feature depletion mode MOSFETs connected to resistive elements, preferably, Positive Temperature Coefficient (PTC) devices, configured in such a way so that the voltage across the PTC device is the same as the gate-to-source voltage of the MOSFET. The circuit may further be configured using a TVS diode, for clamping the drain-to-source voltage of the MOSFET during the overcurrent events. Heat transfer between the MOSFET and the PTC device facilitates overcurrent protection. A two-terminal device including a depletion mode MOSFET, a PTC device, and a TVS diode may provide overcurrent protection to other circuits. A bidirectional circuit c including two MOSFETS disposed on either side of a PTC is also contemplated for AC voltage overcurrent protection.

Abstract: An amplifier overload power limit circuit, system, and a method thereof comprising a monitoring of a current gain of a BJT based on a current detector and limiting power to the BJT based on the monitored current gain to prevent the BJT from driven into a saturation mode and the amplifier overdrive.

Abstract: An intrinsically safe circuit arrangement for supply of electrical power to a consumer having a maximum power requirement, comprising: a voltage source; a voltage monitor for limiting an output voltage to a maximum value; an electrical current limiting resistor for limiting an output electrical current to a maximum value; and an actively controlled electrical current limiting circuit for limiting output electrical current to an electrical current limit value, wherein the electrical current limiting circuit is embodied such that it controls at least the output current to the electrical current limit value as a function of a voltage drop across a part of the electrical current limiting circuit, when a loading of the circuit arrangement above the nominal load is present, such that an adapting of the electrical current limit value occurs, preferably based on a predetermined characteristic curve.

Abstract: A device includes a current monitor, an electronic switch, an energy harvester, and a load controller. The current monitor monitors current drawn by a load coupled to the device and generate an alert signal in response to the monitored current exceeding a predefined threshold value. The electronic switch decouples a battery from the load in response to the alert signal, the electronic switch being electrically disconnected from a negative terminal of the battery coupled to the device. The energy harvester stores energy from the battery while the load is drawing current from the battery. The load controller receives, from the energy harvester, the stored energy from the energy harvester and generates a voltage to power the current monitor to reset the alert signal while the battery is decoupled from the load.

Abstract: Support circuitry for a power transistor includes a feedback switching element and switching control circuitry. The feedback switching element is coupled between a Kelvin connection node and a second power switching node. The switching control circuitry is configured to cause the feedback switching element to couple the Kelvin connection node to the second power switching node after the power transistor is switched from a blocking mode of operation to a conduction mode of operation and cause the feedback switching element to isolate the Kelvin connection node from the second power switching node before the power transistor is switched from the conduction mode of operation to the blocking mode of operation.

Abstract: A drive circuit for airbag systems, for instance includes a differential transconductance amplifier having a first input node, a second input node, an output node coupled to the second input node via a feedback line; a transistor coupled between a drive node and a supply node configured to be coupled to a power supply source; a control node coupled to the control electrode of the transistor and the output node; a Zener diode arrangement having cathode and anode terminals coupled to the supply node and the first input node, respectively; a pull-up component arranged in parallel with the Zener diode arrangement; and an enable switch coupled to the first input node and referred to ground and switchable between a conductive state and a non-conductive state with the differential transconductance amplifier providing controlled current discharging/charging of the control node to make the transistor conductive/non-conductive, respectively.

Abstract: A hybrid switch assembly for use in a circuit interrupter, the hybrid switch assembly including an input, an output, separable contacts electrically connected between the input and the output, a solid state switching circuit electrically connected between the input and the output and in parallel with the separable contacts, and a fuse electrically connected in series with the solid state switching circuit. The solid state switching circuit is structured to turn on and allow current to flow through it between the input and the output for a predetermined amount of time after the separable contacts separate.

Abstract: A reverse current inhibitor includes: at least one diode that is bridged by a first variable resistance element; a sensing circuit; a first switching device for switching the first variable resistance element from a first higher resistance to a second lower resistance in response to a forward current that has passed the diode in its forward direction; and a second switching device for switching the first variable resistance element to a higher resistance in response to the sensing circuit detecting a reverse current corresponding to the reverse direction of the diode. The sensing circuit includes a current-voltage converter that includes a sensing resistor and amplifies a voltage drop over the sensing resistor for one sign of the voltage drop only.

Abstract: Two-transistor devices protect electrical circuits from sustained overcurrent conditions. Some cases provide normally-on depletion mode transistors biased into enhancement mode for lower impedance during normal current conditions, and then the transistors are biased into blocking depletion mode during sustained overcurrent conditions to block the current to the circuit. Optionally, the devices have only two terminals and require no auxiliary power to operate. Other cases provide protective circuitry for the transistors' gates, timing circuitry designed to ignore brief nuisance spikes, and/or timing circuitry to delay resetting the device until the current has returned to an acceptable level.

Abstract: In a short circuit protection circuit, a first gate resistor is connected between a first output node of a gate driver and a first gate terminal. A first real-time control circuit operates to decrease a potential of the first gate terminal when the first real-time control circuit detects that a short circuit current passes through a first semiconductor switching element. The operation monitoring circuit includes a differential voltage circuit configured to output a potential difference between a potential proportional to a potential difference across the first gate resistor and the potential of a first power supply. The operation monitoring circuit monitors, based on an output of the differential voltage circuit, whether the first real-time control circuit is in operation.

Abstract: A current limiting circuit for controlling current from a power supply to a load having a capacitance includes an inductor, a transistor coupled in a current path with the inductor, and a control circuit. The transistor includes a control terminal. The control circuit is coupled to sense a voltage across the inductor and coupled to the control terminal of the transistor. The control circuit is configured to turn off the transistor when the voltage across the inductor is greater than a threshold to restrict current from a power supply, and turn on the transistor when a defined parameter is met to allow current from the power supply to charge the load capacitance. Other example current limiting circuits are also disclosed.

Abstract: This application provides a protective circuit and a display device. The protective circuit includes a control line, a transmission line, and an active switch. The control line transmits a control signal; the transmission line includes an input line and an output line; and a control end of the active switch is electrically coupled to the control line, a first end of the active switch is connected to the input line, and a second end of the active switch is connected to the output line. A protected wire is arranged between the input line and the output line.

Abstract: A simple, low-cost circuit is disclosed that provides the requisite triple redundancy for a spark protection circuit for a battery-operated device having an on-board battery charger that is intended for use in hazardous atmospheres. The circuit complies with the IEC standard for intrinsically safe products.

Abstract: A circuit protective system. The system includes an output controlling enablement of a transistor and an input sensing an operational parameter associated with the transistor. The system also includes detection circuitry providing an event fault indicator if the operational parameter violates a condition. The system also includes protective circuitry disabling the transistor in response to the event fault indicator and subsequently selectively applying an enabling bias to the transistor; the enabling bias is selected from at least two different bias levels and in response to a number of event fault indications from the detection circuitry.

Abstract: Adaptive gate drivers and related methods and systems are disclosed. An example gate driver system includes a comparator, a latch having first and second inputs and outputs, the first input coupled to the comparator, a timer having an input and an output, the input coupled to the first output of the latch, the output coupled to the second input of the latch, control logic having an input and first and second outputs, the input coupled to the second output of the latch, first and second transistors having a gate, a first buffer having an input and an output, the input coupled to the first output of the control logic, the output coupled to the gate of the first transistor, and a second buffer having an input and an output, the input coupled to the second output of the control logic, the output coupled to the gate of the second transistor.

Abstract: An uninterruptible power system described herein includes a first input and a second input and an AC output. The uninterruptible power system also includes power circuitry coupled to the first input, the second input, and the AC output, the power circuitry including an inverter having a first pair of switching elements including a first switching element and a second switching element and a second pair of switching elements including a third switching element and a fourth switching element, wherein the first switching element, the second switching element, the third switching element and the fourth switching element have an identical voltage rating; and a controller coupled to the second pair of switching elements and configured to control the third switching element and the fourth switching element to prevent occurrence of an overvoltage condition.

Abstract: A hybrid construction machine includes: a motor generator system connected to an internal combustion engine and performing a motor generator operation; an electric power accumulation system connected to the motor generator system; a load drive system connected to the electric power accumulation system and being driven electrically; an abnormality detection part equipped to the motor generator system, the electric power accumulation system and the load drive system; and a main control part determining whether an abnormality has occurred based on a detection value of the abnormality detection part. When the abnormality determination part determines that an abnormality has occurred, the main control part stops a drive of a drive system in which the abnormality is detected in the load drive system.

Abstract: When a short-circuit failure has occurred in a power semiconductor device provided in a power module, a radical and rapid temperature increase is prevented by instantly interrupting a short-circuit current. A power module 10 has a package 10a. Provided in the package 10a are: a MOSFET 21 serving as the power semiconductor device; a resistor 23 serving as a detecting means for detecting an operation state of the MOSFET 21 and outputting a detection signal; and a MOSFET 22 serving as a current-interrupting purpose switch connected in series to the MOSFET 21. In response to a control signal Si2 generated on the basis of the detection signal, the MOSFET 22 goes into a conduction state during a normal operation of the MOSFET 21 and goes into an interruption state so as to interrupt a current flowing in the MOSFET 21 when a short-circuit failure has occurred in the MOSFET 21.

Abstract: An overcurrent protection apparatus that protects, from overcurrent, a load circuit including an electric load and wiring electrically connected with each other is provided. The overcurrent protection apparatus includes: a semiconductor switching element that is configured to control energization to the load circuit; and a breaker that stops the semiconductor switching element upon detection of abnormality of overheat or overcurrent at the semiconductor switching element, the breaker having a latch operation mode of continuously stopping the semiconductor switching element even upon cancellation of abnormality detection, and a retry operation mode of canceling stoppage of the semiconductor switching element upon the cancellation of the abnormality detection. The breaker is configured to initially operate in the latch operation mode upon the abnormality detection, and then be switched to the retry operation mode after satisfaction of a predetermined condition.

Abstract: An output circuit including an output transistor configured to provide an output signal; and a gate switch configured to decouple a gate of the output transistor from other components of the output circuit when there is a decrease in a supply voltage of the output circuit, wherein when the gate of the output transistor is decoupled, a charge at the gate is maintained in a capacitor inherent within the gate of the output transistor.

Abstract: An apparatus is provided for monitoring a high-voltage on-board power supply system of an electrically operated vehicle for the occurrence of overloading, wherein the high-voltage on-board power supply system includes as components one or more energy sources and/or one or more energy sinks which are each connected via a conductor line arrangement to a first supply potential line and to a second supply potential line. Each of the components is assigned a current sensor which is designed to detect a current flowing through the respective component and to transmit information representing the level of the current to an evaluation unit for evaluation. The evaluation unit is designed to compare the current with a first current threshold and a second current threshold and to output a switch-off signal at least for the component assigned to the current sensor if, as a first criterion, the level of the current and the duration of the level of the current are between the first and second current thresholds.

Abstract: A circuit comprises a primary transistor connecting a primary voltage source to a load connector. A translator and a secondary transistor cause opening of the primary transistor when receiving an off command and cause closing of the primary transistor when receiving an on command. The secondary transistor is powered by a secondary voltage source. A microcontroller receives measurements of a load voltage at the load connector. The microcontroller detects a drop of the load voltage to determine a moment when the load becomes connected to the circuit while the off command is being issued. The microcontroller issues the on command in response to the determination. Successive brief on commands may be issued to initially control current build-up in the load. A system includes the microcontroller and a plurality of such circuits for powering plural loads.

Abstract: A test system for testing a battery pack having a high voltage terminal, a low voltage terminal, first and second battery modules, and a master microprocessor is provided. The test system includes an inverter unit and a test computer. The inverter unit iteratively grounds the high voltage terminal and the low voltage terminal. The test computer sends a first message to the master microprocessor that requests first and second voltage values of the first and second battery modules. The master microprocessor sends a second message having the first and second voltage values to the test computer which determines a first voltage deviation value. The test computer sets a test flag to a predetermined pass value if the test computer received the second message and the first voltage deviation value is less than a first threshold voltage deviation value.

Abstract: A synchronous rectification controller configured to control a synchronous rectification transistor is provided on the secondary side of an insulated synchronous rectification DC/DC converter. A DRAIN pin receives the drain voltage VDS2 of the synchronous rectification transistor. A pulse generator generates a pulse signal S11 based on the voltage at the DRAIN pin. A driver drives the synchronous rectification transistor based on the pulse signal S11. Upon detecting an open-circuit fault of the DRAIN pin, an abnormality detection circuit asserts an abnormality detection signal S13.

Abstract: A device for driving a fastening element into a substratum comprises a mechanical energy store for storing mechanical energy, an energy transfer apparatus for transferring energy from an electrical energy source to the mechanical energy store, and an electronic control apparatus, which is supplied with electrical energy by the electrical energy source and is suitable for initiating an energy withdrawal process when the supply of energy to the control apparatus by the electrical energy source is interrupted. In the energy withdrawal process, energy possibly stored in the mechanical energy store is converted into electrical energy and fed to the control apparatus in order to supply the control apparatus.

Abstract: An electrical device protection circuit for a smart grid includes a detection unit for detecting whether or not the output power source of an electrical device short-circuits; a switch unit for connecting power, input to the electrical device, to the output power source of the electrical device or disconnect it therefrom; and a control unit for generating a control signal for making the switch unit disconnect the power input to the electrical device from the output power source of the electrical device. According to the electrical device protection circuit for a smart grid, a simply configured protection circuit, arranged in the electrical device, operates when the output power source of the electrical device short-circuits, whereby the electrical device may be prevented from being damaged.

Abstract: A control device that can realize low power consumption even if the temperature of a wire is erroneously calculated. A control unit calculates, for each of one or more wires, a temperature difference between an ambient temperature of the wire and a temperature of the wire over time, and supplies/interrupts an electric current that flows through the wire. The control unit interrupts, for each of the wires, the electric current if the temperature sum of the calculated temperature difference and the ambient temperature is greater than or equal to a first threshold. The control unit measures a time period in which the electric current is being interrupted. If, for each of the wires the calculated temperature difference is less than a second threshold or the measure time period exceeds a predetermined time period, the control unit halts the calculation of the temperature of the wires.

Abstract: There is provided a protection circuit configured to indicate an overcurrent condition of a conductor conducting a load current, the protection circuit including a first current integrator and a second current integrator, each of the first and second integrators being configured to integrate an input voltage proportional to the load current, a summing amplifier configured to receive an offset voltage, to amplify a signal from the second integrator, and to generate a trip threshold based on the input voltage and the offset voltage, and a comparator configured to compare an output of the first current integrator and the trip threshold, and to generate a trip signal at a trip time when the trip threshold is equal to an output of the first integrator, the trip signal indicating an overcurrent condition.

Abstract: Circuits and methods for driving a load are disclosed. An exemplary driving circuit may include first and second switching devices electrically connected with each other in parallel. The driving circuit may also include a current sensing circuit configured to generate a current sensing signal indicating a value of a current flowing through the first switching device. The current sensing signal may include an offset caused by parasitic inductance imbalance in electrical connections connecting the first and second switching devices. The driving circuit may further include a driver circuit configured to control switching operations of the first and second switching devices. The driver circuit may include an overcurrent protection circuit electrically connected to the current sensing circuit.

Abstract: A semiconductor device includes a transistor, a diode, a first detection circuit, a second detection circuit, a calculation circuit, and a determination circuit. The diode is connected in reverse parallel with the transistor. The first detection circuit is configured to detect a change rate of a gate voltage of the transistor with respect to time. The second detection circuit is configured to detect a gate current of the transistor. The calculation circuit is configured to calculate a gate capacitance based on the change rate of the gate voltage with respect to time, and the gate current. The determination circuit is configured to determine, based on a determination result of the gate capacitance when a charge is injected to a gate of the transistor, whether a current flows to the diode or to the transistor.

Abstract: In a power transfer system, a first main switch can transfer power from a first connector to an output terminal. A first path can deliver a current from the first connector to the output terminal and control the current to be within a predefined ranger. A second main switch can transfer power from a second connector to the output terminal. A second path can deliver a current from the second connector to the output terminal and control the current to be within a predefined range. Control circuitry can turn off the second main switch and the second path and turn on the first path if the first power source is available at the first connector when the second power source is providing power to the output terminal. The control circuitry can turn on the first main switch when a time interval from turning on the first path has elapsed.

Abstract: A hybrid-type construction machine includes: a motor generator system connected to an internal combustion engine and performing a motor generator operation; an electric power accumulation system connected to the motor generator system; a load drive system connected to the electric power accumulation system and being driven electrically; an abnormality detection part equipped to the motor generator system, the electric power accumulation system and the load drive system; and a main control part determining whether an abnormality has occurred based on a detection value of the abnormality detection part. When the abnormality determination part determines that an abnormality has occurred, the main control part stops a drive of a drive system in which the abnormality is detected in the load drive system.

Abstract: A non-isolated power supply is configured to receive an input voltage and supply an output voltage, and includes a supply line, a return line, a first semiconductor switch coupled in series in the supply line, and a second semiconductor switch coupled in series in the return line. The first and second semiconductor switches are each configured to operate in an ON state and an OFF state. The differential current sensor is configured to sense differential current between the supply line and the return line. The fault detection logic is coupled to the differential current sensor, the first semiconductor switch, and the second semiconductor switch, and is configured to detect when the differential current exceeds a predetermined current magnitude, and command the first and second semiconductor switches to operate in the OFF state upon detecting that the differential current exceeds the predetermined current magnitude.

Abstract: An autonomous thermal event control and monitoring system includes a processor component having an enclosure, a processor within the enclosure, a routine, a number of inputs from the processor, and a plurality of inputs to and a plurality of outputs from the processor for each of a plurality of feeders. The system also includes a human machine interface communicating with the processor. The inputs include for each of the feeders, a first input for a thermal sensor and a second input for a status of a network protector, a plurality of third inputs for statuses of a medium voltage interrupter, and a fourth input for a sudden pressure sensor of a network transformer. The outputs include for each of the feeders, a first output for a command to the network protector, and a plurality of second outputs for commands to the medium voltage interrupter.

Abstract: A current limiting circuit for a motor controller includes a comparator. The comparator has a sensed current input, a current threshold input, and an overcurrent protection trip output. A variable resistance current threshold circuit is connected to the current threshold input. A first controller is connected to the variable resistance current threshold circuit via a plurality of connections. The first controller is configured to control a voltage output of the variable resistance current threshold circuit.

Abstract: A determination is made as to when the current flowing through a transistor exceeds a predetermined threshold. When the current exceeds the predetermined threshold, the transistor is deactivated. The deactivating of the transistor is effective to limit the current that flows through the transistor. The limiting of the current is effective to prevent damage to the transistor in an over current condition. The transistor is maintained in a deactivated state until a time off circuit resets the DC-DC converter circuit. The maintaining of the transistor in the deactivated state until a time off circuit resets the DC-DC converter circuit is additionally effective to reduce the time on (Duty Cycle—D.C.) and frequency to further prevent damage to the transistor due to switching power losses.

Abstract: A power circuit is described that includes a switch coupled to a resistive-inductive-capacitive load and a driver coupled to the switch. The driver is configured to detect an emergency event within the power circuit. After detecting the emergency event within the power circuit, the driver is further configured to perform a controlled emergency switch-off operation of the switch to minimize the maximum temperature of the switch during the detected emergency event and switch-off operation.

Abstract: Techniques are described for determining whether a switch circuit experienced one of a latched overload condition and an open load with no input voltage condition. In the techniques, a first diagnostic signal is output if the switch circuit experienced the latched overload condition. Also, in the techniques, a second, different diagnostic signal is output if the switch circuit experienced the open load with no input voltage condition.

Abstract: A semiconductor device includes: an output transistor; and a current detection section. The output transistor controls electric power supply from an electric power source to a load. The current detection section detects a current flowing through the output transistor. The current detection section has a current detection characteristic in which a current detection value has approximately linier and negative dependence on a drain-source voltage of the output transistor.

Abstract: Method for performing maintenance of an electric installation including at least one electric equipment unit comprising: entry and storing in a database of data representative of an electric installation to be monitored and of data representative of electric equipment settings and parameters, storing of data representative of events in a database so as to constitute an events history, detection of malfunctioning disturbances, analysis of causes of malfunctioning of the electric installation, management of restoration of operation of a part of the installation. Management of restoration of operation comprises monitoring by a decision tree to evaluate a criticality level.

Abstract: High performance gate drives and methods for driving semiconductor switching elements, such as insulated gate bipolar transistors (IGBTs), are provided. The gate drive can control the voltage applied to the gate of the IGBT to one or more intermediate voltages near the threshold voltage of the IGBT to control dv/dt of the collector-emitter voltage during and the di/dt of the collector current turn off. For instance, a voltage level between the turn on voltage and the turn off voltage can be applied for a first time period to control dv/dt of the collector-emitter voltage and di/dt of the collector current during turn off. Another voltage level between the turn on voltage and the turn off voltage can be applied for a second time period during reverse recovery of a freewheeling diode coupled in parallel with the IGBT.

Abstract: An electronic temperature sensor for measuring the junction temperature of an electronic power switch (4) of a static converter (8) includes an injection source of a calibrated measurement current (20) and a differential voltage measurement amplifier (76; 276). The electronic temperature sensor includes a first series connection (26) element and a second series connection (28) connected respectively to the inlet terminals (78, 80) of the differential voltage amplifier (76; 276). The first and second series connection elements (26, 28; 224, 226) are configured to protect the amplifier against a high voltage, have essentially identical electrical characteristics and are included in the set formed by resistances and high-voltage (HV) rapid diodes.

Abstract: An opto-acoustic subsystem is provided. The subsystem includes an optical transmitter and an actuator device. The optical transmitter can be positioned at a surface of a wellbore. The actuator device can be positioned in the wellbore and can respond to a modulated electrical signal generated from a modulated optical signal received from the optical transmitter by outputting a modulated acoustical signal into an environment of the wellbore.

Abstract: A signal receiver may include a limiter and an amplifier that is connected to the limiter. The limiter may receive an input signal, generate a limited signal using the input signal, limit values of the limited signal in a first range, and output the limited signal. The amplifier may receive the limited signal, generate an output signal using the limited signal, and output the output signal, wherein values of the output signal are in a second range, and wherein the second range is larger than or equal to the first range.