423 results about "Current switch" patented technology

The invention discloses a three-port soft switching optical storage servo all-in-one machine based on device multiplexing and a modulation method. The all-in-one machine comprises a DC-AC servo driver, a low-voltage DC energy storage module, an auxiliary unit, a bus capacitor and a photovoltaic module. The DC-AC servo driver comprises three bridge arms, and each bridge arm is provided with a bridge arm upper tube and a bridge arm lower tube; the low-voltage direct-current energy storage module comprises an energy storage battery, an energy storage switch tube S7 and a direct-current energy storage inductor; the photovoltaic module comprises a photovoltaic power generation panel, a photovoltaic inductor, a photovoltaic switch tube S8 and a diode D1; the auxiliary unit comprises an auxiliary switch tube Sa, an auxiliary resonant inductor Lr and an auxiliary capacitor Cr. According to the invention, an integrated resonant soft switching architecture is innovatively adopted, zero-voltage / zero-current switching of all power switching devices is realized, and the problem of loss caused by a traditional hard switch is thoroughly solved; and by optimizing a device multiplexing technology, the number of switching tubes is greatly reduced while the soft switching performance is ensured, so that the system efficiency is improved in a breakthrough manner.

The invention discloses a CMOS analog multiplier circuit, the circuit comprises a current-to-voltage circuit and a multiplier sub-circuit connected with the current-to-voltage circuit, an OSC circuit in the multiplier sub-circuit receives an input voltage VB and a reference voltage VREF and generates a two-phase non-overlapping clock signal group, a voltage-to-current A circuit converts a voltage VA into a current iA, and the current iA is connected with the OSC circuit. The switched capacitor integrating circuit inputs a sampling voltage to the voltage-to-current B circuit and integrates a difference current is of a current iA and a current iB to realize multiplication, the voltage-to-current B circuit converts a sampling voltage signal into the current iB, and the current-to-voltage circuit converts the current iB into an output voltage Vo as a multiplier operation result. Through combination of modular design, a current mode method and a switched capacitor method and high-precision current conversion and integration processes, an efficient and accurate multiplication simulation function is realized, a THD enhancement function is introduced through multiplexing design, and circuit performance is further optimized.

The invention provides a totem pole PFC circuit control method and a power conversion device. The totem-pole PFC circuit comprises a first inductor, a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm are connected in parallel between the positive electrode and the negative electrode of the DC interface of the totem-pole PFC circuit, the first end of the first inductor is connected to the midpoint of the first bridge arm, and the second end of the first inductor and the midpoint of the second bridge arm are used for being connected with an AC power supply. The method comprises the following steps: controlling switch tubes of a first bridge arm and a second bridge arm to be closed within a first duration starting from a first moment before each zero-crossing moment of an alternating current power supply, and controlling a main switch tube of the first bridge arm to work within a second duration starting from a second moment after the zero-crossing moment, the follow current switch tubes of the second bridge arm and the first bridge arm are controlled to be closed; wherein the last moment of the first duration is the second moment. According to the control method provided by the invention, the leakage current of the power conversion device comprising the totem-pole PFC circuit can be effectively reduced.

The invention discloses a formation and capacity grading parallel detection system based on a high-voltage direct-current bus. A press device comprises a direct-current switch and at least one set of pull-out type charging and discharging probe module. And the input end of the direct-current switch is connected with the output end of the PCS equipment. Each charging and discharging probe module adopts a pull-out structure and comprises a mechanical frame, and a high-voltage direct-current bus, a bidirectional conversion module and a probe assembly which are integrally mounted in the mechanical frame; the high-voltage direct-current bus input end is connected with the direct-current switch output end; the bidirectional conversion module comprises two stages of conversion units; the first conversion unit is used for reducing the first voltage of the high-voltage direct-current bus into the second voltage or reversely increasing the voltage; the second conversion unit reduces the second voltage to the voltage required by charging and discharging of the battery or boosts the second voltage; the probe assembly is connected to the output end of the second conversion unit. The system is compact in structure, high in charging and discharging efficiency and convenient to maintain, and cables are saved.

The invention relates to the technical field of power equipment testing, in particular to a high-voltage direct-current switch integrated equipment aging test platform which comprises a multi-dimensional interface adaptation module, a collaborative aging test module, an aging feature extraction module and a cyclic test control module. The multi-dimensional interface adaptation module realizes rapid access and standardization by acquiring device interface features and comparing and adjusting, cooperates with the aging test module to synchronously apply four stresses, obtains a dynamic acceleration factor quantitative acceleration effect through a coupling formula, the aging feature extraction module extracts related parameters, quantifies the degradation degree in combination with a dynamic weight formula, and finally obtains the aging test result. The cycle test control module adjusts the cycle index according to the acceleration factor and the degradation degree and in combination with the fluctuation amplitude, rapid equipment adaptation is achieved, the composite aging process can be accurately reproduced, the test process is dynamically optimized, the test standardization level, the consistency with the actual working condition and the test efficiency are remarkably improved, and the test efficiency is improved. And reliable technical support is provided for equipment aging characteristic evaluation.

The invention relates to the technical field of power management, in particular to a two-way switching LDO framework suitable for an MCU sleep mode. Comprising a main LDO, an auxiliary LDO and a current detection circuit. The main LDO comprises a second error amplifier and a second adjusting tube; the auxiliary LDO comprises a first error amplifier and a first adjusting tube; the main LDO and the auxiliary LDO share the same voltage feedback network, and the voltage reference and the feedback output of the voltage feedback network are connected with the input end of the first error amplifier and the input end of the second error amplifier at the same time. The outputs of the first adjusting tube and the second adjusting tube are short-circuited and then are output to the MCU, and are simultaneously input to the input end of the voltage feedback network; the input end of the current detection circuit is connected with the output end of the first error amplifier, and the output end is connected with the current switch of the second error amplifier. The architecture provided by the invention meets the requirements of low power consumption and quick response of the MCU, and the power consumption of the architecture is not influenced by the power consumption of the MCU.

The invention discloses a magnetic suspension displacement device in a vacuum interconnection system. The magnetic suspension displacement device comprises a bearing table; the magnetic driving unit comprises a plurality of electromagnets which are arranged in an annular array, the plurality of electromagnets are divided into a plurality of groups, each group comprises two electromagnets which are collinear in the radial direction, the magnetic pole directions of the electromagnets are parallel to the radial direction, and the magnetic pole directions of the electromagnets in the same group are the same; the current switching mechanism is used for controlling the electromagnets to be sequentially switched on and off in the first direction, and the electromagnets in the same group are synchronously switched on and off to simulate rotation of the magnets to generate a balanced magnetic field; the sample table and the bearing surface are oppositely arranged at intervals; the stator is arranged in the sample table to generate a magnetic field repulsive to the balance magnetic field so as to suspend the sample table; the displacement driving unit is used for driving the bearing table to move. According to the invention, the sample table can be stably suspended and fixed at a position opposite to the bearing table, no mechanical vibration is generated, the switching frequency and the magnetic force are adjustable, the stability and controllability of the sample table in the start-stop state are improved, and the application is suitable for vacuum interconnection systems of wafer production lines with different sizes.

The invention discloses a rapid spare power automatic switching device and method suitable for high-proportion distributed power supply access, and the device comprises a local sampling module which is used for collecting a local side bus voltage Ulocal and an incoming line current Ilocal; the switching value acquisition module is used for acquiring the TWJ state of the switch at the side; the communication module is used for communicating with an opposite-side remote transmission device through an HDLC protocol and acquiring opposite-side switch position information Kremote and an opposite-side voltage state Uremote; programmable logic is arranged in the logic processing module, and the logic processing module is used for executing comprehensive judgment logic; and the control output module is used for executing opening and closing operation of the switch according to the instruction of the logic processing module. Compared with a traditional spare power automatic switching technology, the method effectively solves the problems of operation refusal and maloperation caused by access of the high-proportion distributed power supply, and remarkably improves the power supply reliability and the new energy consumption capability.

The invention discloses an anti-radiation low-phase noise voltage-controlled oscillator based on an SOI (Silicon On Insulator) process, relates to the technical field of oscillators, and is used for solving the technical problem that the existing voltage-controlled oscillator based on the SOI process cannot realize low phase noise and high anti-radiation capability at the same time. The anti-radiation low-phase noise voltage-controlled oscillator based on the SOI technology comprises an energy storage unit and a negative transconductance unit. The energy storage unit forms a resonant cavity through an inductor and a capacitor; the negative transconductance unit is connected with the energy storage unit; the negative transconductance unit at least comprises a first cross-coupled pair and a second cross-coupled pair which are formed by a plurality of transistors; the first cross coupling pair is used for generating negative resistance to compensate the loss of the energy storage unit, and the second cross coupling pair serves as a current switching network; the first cross coupling pair and the second cross coupling pair form a negative resistance characteristic, direct-current energy is converted into alternating-current oscillation energy, loss of the resonant cavity is compensated, and a generated oscillation signal is output from the output node.

A controller for a multiphase voltage regulator in a multi-rail power supply system has a dynamic overcurrent unit and a switch control circuit. The dynamic overcurrent unit provides an overcurrent threshold based on a system-input current which indicates a total input current of the multiphase voltage regulator and at least another voltage regulator. The switch control circuit provides a plurality of switch control signals to control a plurality of switching circuits of the multiphase voltage regulator, such that an output voltage of the multiphase voltage regulator is regulated to a predetermined voltage level and an output current of the plurality of switching circuits is controlled based on the overcurrent threshold.

The utility model relates to the technical field of high-voltage cascade energy storage systems, and discloses a valve hall type high-voltage cascade energy storage system based on nested power modules, which comprises three phases of chain type energy storage bridge arms respectively connected with three phase lines of a power grid, and each phase of chain type energy storage bridge arm comprises a plurality of cascaded nested power modules. Each nested power module comprises a plurality of direct-current energy storage units and an H-bridge circuit, the plurality of direct-current energy storage units are connected in parallel and then connected with the direct-current side of the H-bridge circuit, and the alternating-current side of the H-bridge circuit is connected with an alternating-current switch; the DC energy storage unit comprises a battery cluster and a DCDC converter connected with the battery cluster in parallel, the DCDC converter comprises a first capacitor, a second capacitor and a power conversion unit, and the power conversion unit comprises three full-control semiconductor devices and an inductor. According to the utility model, each battery cluster is accurately controlled through the DCDC converter in the embedded power module, so that the reliability of the valve hall type high-voltage cascade energy storage system is improved.

This suppresses power waste caused by discharging residual charge. [Solution] The emitter 10 of the distance measuring device 1 for measuring the distance to an object comprises a transmitting unit that outputs a transmission wave to irradiate the object, a capacitor 120 that is charged by a power supply and supplies current to the transmitting unit, a switching element 150 that controls the current flowing to the transmitting unit, a drive circuit that controls the switching element, and a control unit 180 that, after irradiating with a transmission wave, sends a control signal to the drive circuit to continuously irradiate with a transmission wave of an irradiable distance according to the residual charge of the capacitor 120.

The invention discloses a tripper, a direct-current switch control method of a power converter and an application device of the tripper, and relates to the technical field of power electronics. The release is provided with two execution mechanisms which respectively receive corresponding signals, so that the state of the release is controlled by the two execution mechanisms at the same time; when an application device of the release enters a power-off state from a non-running state, the state of the release is a pull-in state, at the moment, a switch body connected with the release can be freely opened and closed, and tedious operation after a fault is eliminated when an under-voltage release is adopted is avoided; when the application equipment enters the power-off state from the operation state, the state of the release is a release state, and at the moment, the switch body connected with the release is disconnected and cannot be switched on, so that the risk of fault expansion caused by manual switching on when the fault is not eliminated by adopting the shunt release is avoided; and furthermore, targeted tripping actions can be carried out under different power loss conditions, and the requirements under different conditions are considered.

The invention discloses a switching operation command issuing method and system based on networking and a medium, mainly relates to the technical field of switching operation commands, and is used for solving the problems that in the prior art, manual input errors exist, checking and transmission efficiency is low, manual judgment is possibly affected by factors such as emotion and pressure, and decision errors are caused. Comprising the following steps: generating a switching operation command which has reverse symmetry or reversion with a current switching operation command; inputting the switching operation command into a preset operation command checking rule program to obtain a checking result corresponding to the switching operation command; obtaining return information returned by the operation terminal through the to-be-returned interface, and giving an alarm and intercepting issuing operation when the return information does not belong to the same operation unit and station name; determining an issuing mode of a switching operation positive order; obtaining a preset positive order comparison group and a preset pre-order comparison group; and judging whether the preset positive command comparison group is the same as the preset pre-command comparison group or not, generating a comparison result, and issuing the comparison result to a preset operation and maintenance terminal.

This invention discloses a leakage current detection method for an industrial robot electrical cabinet, including port P1. The leakage current detection method is as follows: Current flows through the PE (protective earth) and through the current transformer L1. When the current I1 flowing through the primary and secondary sides of L1 increases; the principle of the current transformer is: N1 / N2 = I2 / I, resulting in I2 = I1*N1 / N2; therefore, the current I2 flowing through the secondary side of the current transformer L1 also increases; when there is no leakage current in the cabinet, there is no current or the current on the PE is very small, U- < 5V; the voltage at the non-inverting terminal of the comparator is greater than the voltage at the inverting terminal, Vout = H, and the output pin 1 of the LM393D is high, and the LED is constantly lit. Based on the characteristics of the electrical cabinet, this invention eliminates the need for a leakage current switch. By designing a current detection circuit flowing through the PE, it determines whether there is a leakage current in the equipment. Its setup cost is lower than that of installing a leakage current protection device.

The invention relates to the technical field of power control, in particular to a filter and leakage inductance collaborative design method of a single-stage bidirectional high-frequency isolation inverter, which comprises the following steps: acquiring basic design parameters, constructing an inverter modulation model according to a modulation strategy, and solving the model to obtain a modulation signal expression; deriving a zero-current switching current constraint condition and a zero-voltage switching current constraint condition of the switching tube based on a modulation strategy; combining the constraint condition with an inverter modulation model, and solving to obtain a soft switching constraint condition; according to the soft switching constraint condition and the value range of the modulation signal expression, determining a collaborative value range of the filter inverter side inductance and the transformer leakage inductance meeting the soft switching requirement; and selecting design parameters of inverter side inductance and transformer leakage inductance of the filter, and determining other circuit parameters of the filter according to a reactive power demand and a grid-connected harmonic standard. According to the invention, the problems of soft switching failure, loss increase and electromagnetic interference caused by parameter mismatching can be effectively suppressed.

The invention discloses a solid-state power controller resonance mode zero-voltage switching-on method based on variable inductance, belongs to the technical field of power electronic conversion, and aims to solve the problems that when a solid-state power controller is started, the peak stress of a device is large, the heat dissipation requirement is large, and the load adaptability is poor. The circuit comprises a resonant network, a main loop power tube and an auxiliary power tube, wherein the resonant network consists of a variable resonant inductor and a pre-charging capacitor; a variable resonant inductor is used for performing parameter matching on different resistive, inductive and capacitive loads to control a resonant mode to be in a critical damping state, so that a pre-charging capacitor discharges in a fastest non-oscillation manner to realize zero-voltage switching on of a main power tube and zero-current switching on and off of an auxiliary power tube; a resonant cavity energy recovery device is arranged to transmit resonant energy to a load. The circuit significantly reduces peak stress when a main loop device is started, reduces switching loss of an auxiliary loop device, recovers resonance energy to a load end, reduces heat dissipation requirements, adapts to load scenes with different properties, and is suitable for the field of high power and high reliability.

The invention provides an inverter, an inverter alternating current switching-on method, a controller and a power conversion system, and relates to the technical field of power electronics. According to the inverter, by means of alternating-current PID protection equipment connected inside or outside the grid side of the inverter, under the condition that the common-mode voltage difference between the two sides of an alternating-current switch is larger than or equal to a threshold value, a control module controls the alternating-current PID protection equipment to output voltage so as to reduce the common-mode voltage difference to be smaller than the threshold value, and then the alternating-current switch is controlled to be switched on; namely, the common-mode voltage difference is reduced by means of the alternating current PID protection device, so that the surge current during alternating current switching-on is reduced, the risk of ablation of a contact of an alternating current switch is reduced, and the influence on the service life of the inverter is further reduced.

The invention discloses a privacy protection method and system for vehicle-mounted data. The method comprises the following steps: acquiring a switching signal of target vehicle network connection setting set by a user; wherein the switching signal is used for indicating a current switching state of target vehicle network connection setting set by a user; according to the switching signal, judging whether the vehicle executes target vehicle networking setting set by a user or not; if the vehicle executes the target vehicle networking setting set by the user, storing the current on-off state of the target vehicle networking setting so as to share or close the vehicle-mounted data corresponding to the target vehicle networking setting; and after the current state is stored, displaying the current on-off state of the network connection setting of the target vehicle to the vehicle machine. Therefore, the user can freely select which data the user wants to share according to his / her own thought or open part of functions in a self-defined manner, the privacy of the user can be protected to a certain extent, and the sensitive data of the user can be protected more finely according to the selection of the user.

The present invention discloses a current-source high-frequency link matrix inverter topology with soft switching, comprising a sequentially connected power supply network, a current-source H-bridge, a series resonant tank, a high-frequency transformer, a matrix converter, a CL filter, and a load. The present invention uses series resonance to match the leakage inductance current of the high-frequency transformer with the DC-side input current, thereby avoiding large voltage spikes on the primary side of the high-frequency transformer and achieving zero-current switching of the current-source H-bridge. The present invention is also well-suited for high-frequency transformers with large leakage inductance. Furthermore, the proposed decoupling-based SPWM and SVM modulation methods for current-source matrix inverters feature mixed high- and low-frequency modulation, enabling safe commutation, effectively reducing the switching frequency of the matrix converter, and providing soft switching conditions for all switches in the matrix converter.

The utility model discloses a multi-source input composite frequency converter, which comprises a sheet metal shell, the front surface of the sheet metal shell is fixedly connected with a sheet metal cover plate, one side of the bottom of the sheet metal shell is provided with a photovoltaic input interface, and the bottom of the sheet metal shell is provided with a 220V alternating current input interface at one side of the photovoltaic input interface. A 380V alternating current input interface is arranged at the bottom of the metal plate shell and located on one side of the 220V alternating current input interface, a direct current switch is arranged at the bottom of the metal plate shell, and a 380V alternating current switch is arranged at the bottom of the metal plate shell and located on one side of the direct current switch. The utility model relates to the technical field of frequency converters, and solves the problems that in the prior art, a frequency converter mostly adopts single power supply input, and different power supplies cannot be flexibly switched and used according to actual requirements, so that the function and the application range of the frequency converter are limited to a certain extent, and the requirements of various complex working conditions are difficult to meet.

The memory device includes: a memory cell array comprising a plurality of memory cells; and a voltage generator configured to supply voltage to the memory cell array. The voltage generator includes a charge pump circuit, a switching circuit, and a stage controller. The charge pump circuit includes a plurality of pump units and is configured to output a pump voltage and a pump current based on the number of pump units that have received an input voltage. The switching circuit is configured to output the pump voltage. The stage controller is configured to receive an input signal corresponding to the pump current and perform a stage control operation to generate a stage control signal for controlling the number of pump units to be driven.

A power tool comprises a housing, a motor within the housing, a current-switching circuit configured to control the current supplied to the motor from a power source, and an electronic control unit. The electronic control unit is connected to the sensor and the current-switching circuit. The electronic control unit is configured to control the current-switching circuit to apply a smooth braking force, to control the line angle and phase lead angle to increase the smooth braking force, and, in response to the line angle reaching its maximum and the phase lead angle reaching its maximum, to control the current-switching circuit to apply a sharp braking force.

The invention relates to an automatic tool test circuit and test method based on a super capacitor. The automatic tool test circuit comprises a control unit, a switch S3, a super capacitor C16, a resistor R57, a current-limiting resistor R35, a resistor R56 and a to-be-tested module. The control unit is used for controlling on and off of the switch S3; the positive electrode of the super capacitor C16 is sequentially connected with a resistor R57, a switch S3 and a resistor R56 in series, and the negative electrode of the super capacitor C16 is grounded; the module to be tested comprises a sampling resistor R34 used for detecting an overcurrent and generating a voltage difference; the first end of the sampling resistor R34 is connected with the second end of the resistor R56, and the second end of the sampling resistor R34 is grounded; the super capacitor C16 is used for storing electric energy and providing current at the moment of discharging, the super capacitor C16 discharges at the moment of closing of the switch S3, and instantaneous current is generated on the sampling resistor R34. The method is low in cost, safe, reliable and easy to implement in factory flow line production, and remarkable competitive advantages are provided for enterprises.

The utility model provides an RMP testboard and test system, which comprises a testboard body, a panel arranged at the front end of the testboard body and a backboard arranged at the rear end of the testboard body, and is characterized in that the panel comprises a voltage and current monitoring area provided with a voltmeter and an ampere meter and used for monitoring voltage and current; the switch area is provided with a power switch area and a discrete magnitude control switch area; the connecting area is provided with a connector J1; the test area is provided with a test hole area and a test indicating lamp area; wherein the test hole area is provided with a power supply output test hole, a discrete magnitude output test hole, a 429 bus test hole and a grounding hole; the back plate is provided with a power input interface; the RMP test board is simple in overall structure and low in manufacturing cost and later maintenance cost, the RMP test board is in communication connection with the to-be-tested panel, the bus analyzer and the oscilloscope are combined to achieve RMP function testing, limitation of special test equipment is eliminated, practicability is high, and the RMP test board is suitable for application and popularization.

This application relates to a diode spike current suppression circuit, comprising: a first switching unit, a current sampling unit, an impedance switching module, and a switching control module; the first switching unit, the current sampling unit, and the impedance switching module are connected in series, and this series line is connected in parallel with the diode being protected; the first output terminal of the switching control module is connected to the control terminal of the first switching unit, and is used to adjust the current flowing through the first switching unit; the second and third output terminals of the switching control module are respectively connected to the impedance switching module, and are used to adjust the impedance of the impedance switching module. The solution of this application adjusts the current flowing through the first switching unit by regulating the conduction time of the first switching unit, and adjusts the current in the circuit by adjusting the impedance value of the impedance switching module connected in the circuit; this avoids long-term operation in a high-impedance circuit, greatly reducing power loss.

The application provides a container type water-cooled data center and a control method, and belongs to the technical field of temperature control. The container type water-cooled data center comprises a computing power service cabinet system, a pump station control system, a plate unit and a power distribution cabinet unit arranged in a container, and further comprises an external liquid cooling system. The computing power service cabinet system comprises a plurality of independently operated modules, each module comprises a plurality of server cabinets, each server cabinet corresponds to a power distribution branch, the plurality of power distribution branches in the same module are collected into the same power distribution bus, the plurality of power distribution buses in the plurality of modules are collected into the same power distribution bus, and the power distribution bus is provided with a current switch for controlling the power distribution bus. The liquid cooling system cools and dissipates heat for the computing power service cabinet system through circulation of a medium. The plate unit serves as a bypass branch of the liquid cooling system and undertakes the heat exchange function of the liquid cooling system in part or in whole. The pump station control system provides power for the circulation of the medium. The application has high integration, small space occupation, high density in unit space, and is safe and reliable.

The invention provides a DC step-down conversion device, a control method and an optical storage DC flexible system, and relates to the technical field of power electronic converters, and the DC step-down conversion device comprises a step-down conversion unit and a controller. The high-voltage side power supply is connected with the load through the step-down conversion unit; the step-down conversion unit comprises three BUCK branches which are connected in parallel and an energy storage inductor, each BUCK branch comprises switch tube groups which are connected in series, each switch tube group comprises a rectification switch tube and a follow current switch tube which are connected in series, a flying capacitor resonance network is connected between the two switch tube groups, and each BUCK branch is connected with a load through the energy storage inductor; and the controller is connected with the step-down conversion unit, and drives the three BUCK branches to be sequentially conducted at a 120-degree phase difference based on the pulse width modulation signal so as to realize interleaving parallel operation. The current ripples output by the circuit are reduced, the requirement for the size of an energy storage element and electromagnetic interference are reduced, the loss of a switching tube is reduced, and the overall conversion efficiency and the operation stability and reliability of the device are improved.

An imaging system comprises a pixel array configured to generate a plurality of image charge voltage signals in response to incident light, and readout circuitry coupled to the pixel array, the readout circuitry including a plurality of column unit cells. Each column unit cell comprises at least one of a plurality of comparators, wherein each comparator is coupled to receive the ramp signal from the ramp generator through a ramp signal line. Each column unit cell also comprises a compensation current unit coupled to the ramp signal line, each compensation current unit comprising a compensation current source and a compensation current switch coupled to the compensation current source, wherein the compensation current source and the compensation current switch are coupled between a first node on the ramp signal line and a second node.

To provide a current switching DAC that achieves both a low power consumption and a high-speed operation.SOLUTION: A current switching DAC 101 that converts an input of a plurality of digital input signals into an analog output signal is provided corresponding to each of a plurality of digital input signals D<1> to D<n> and DB<1> to DB<n>. Each of them includes: a plurality of unit current sources I1<1> to I1<n> capable of supplying a predetermined current according to a corresponding digital input signal; a pair of output terminals IOUT and IOUTB respectively connected to the plurality of unit current sources and outputting a sum of predetermined current values of the unit current sources; and a bias voltage supply part 10 outputting a bias voltage Vbias to be supplied to each of the plurality of unit current sources. Each unit current source includes: a differential switch for switching a current path of an output terminal; a bias voltage control circuit for controlling supply of a bias voltage; and a bias control signal generation circuit for generating a control signal of the bias voltage control circuit.SELECTED DRAWING: Figure 1