Circuit device and power conversion circuit

Abstract

The invention provides a circuit device and a power conversion circuit, which can easily recognize an alarm signal and a state signal. The circuit device includes: a power conversion circuit; and a transmission device that transmits a signal from the power conversion circuit, the power conversion circuit having: an alarm signal generation unit that generates an alarm signal indicating whether or not the power conversion circuit is in a preset state; and a state signal generation unit that has an amplitude different from that of the alarm signal and generates a state signal indicating the state of the power conversion circuit. The power conversion circuit may further have an output terminal that outputs an output signal in which the alarm signal and the state signal are superimposed.

Description

Technical Field

[0001] The invention relates to a circuit device and a power conversion circuit. Background Art

[0002] Conventionally, in a circuit such as a power conversion circuit, there is known a technique for outputting an alarm signal indicating abnormality of the circuit or a temperature information signal indicating the temperature of the circuit to the outside (see, for example, Patent Documents 1 to 3).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2014-93903

[0004] Patent Document 2: Japanese Patent Application Publication No. 2011-172336

[0005] Patent Document 3: Japanese Patent Application Publication No. 2020-96436 Summary of the invention

[0006] Technical issues

[0007] It is preferable that the alarm signal and the status signal indicating the status of the temperature or the like can be easily distinguished.

[0008] Technical Solution

[0009] In order to solve the above-mentioned problems, in one embodiment of the present invention, a circuit device is provided, which has a power conversion circuit and a transmission device for transmitting a signal from the power conversion circuit. In the above-mentioned circuit device, the power conversion circuit may have an alarm signal generating unit, and the alarm signal generating unit generates an alarm signal indicating whether the power conversion circuit has reached a preset state. In any of the above-mentioned circuit devices, the power conversion circuit may have a state signal generating unit, and the state signal generating unit generates a state signal having an amplitude different from that of the alarm signal and indicating the state of the power conversion circuit.

[0010] In any of the above circuit devices, the power conversion circuit may include an output terminal configured to output an output signal in which the alarm signal and the state signal are superimposed.

[0011] In any of the above circuit devices, the alarm signal generating unit can switch whether a reference voltage or a first power supply voltage different from the reference voltage is applied to the output terminal. In any of the above circuit devices, the state signal generating unit can switch whether an intermediate voltage or the first power supply voltage is applied to the output terminal, the intermediate voltage being closer to the first power supply voltage than the reference voltage.

[0012] In any of the above circuit devices, the power conversion circuit may include a reference wiring to which the reference voltage is applied. In any of the above circuit devices, the power conversion circuit may include a power supply wiring to which the first power supply voltage is applied. In any of the above circuit devices, the state signal generation unit may include a first switch provided between the reference wiring and the power supply wiring. In any of the above circuit devices, the state signal generation unit may include an intermediate voltage generation unit provided between the first switch and the reference wiring and generating the intermediate voltage.

[0013] In any of the above-described circuit devices, the alarm signal generating section may include a second switch that switches which of the reference voltage and the first power supply voltage is applied to the output terminal.

[0014] In any of the above circuit devices, the transmission device may include a first transmission section that transmits a component of the output signal having an amplitude greater than a first reference value. In any of the above circuit devices, the transmission device may include a second transmission section that transmits a component of the output signal having an amplitude greater than a second reference value. In any of the above circuit devices, the first reference value may be smaller than the second reference value.

[0015] In any of the above circuit devices, the amplitude of the state signal may be greater than the first reference value and less than the second reference value. In any of the above circuit devices, the amplitude of the alarm signal may be greater than the second reference value.

[0016] In any of the above circuit devices, the amplitude of the state signal may be greater than the second reference value. In any of the above circuit devices, the amplitude of the alarm signal may be greater than the first reference value and less than the second reference value.

[0017] In any of the above-mentioned circuit devices, the power conversion circuit may have an amplitude switching unit that switches which of the alarm signal and the status signal has an amplitude greater than the second reference value and which has an amplitude greater than the first reference value and less than the second reference value.

[0018] In any of the above circuit devices, the transmission device may include a second power supply voltage generating unit that generates a second power supply voltage between the reference voltage and the intermediate voltage. In any of the above circuit devices, the transmission device may include a first transmission unit that outputs a signal corresponding to a difference between the first power supply voltage and a voltage of the output terminal. In any of the above circuit devices, the transmission device may include a second transmission unit that outputs a signal corresponding to a difference between the second power supply voltage and a voltage of the output terminal.

[0019] In any of the above-mentioned circuit devices, the second power supply voltage generating unit may be a power supply that generates the second power supply voltage with reference to the reference voltage, and the second power supply voltage may be higher than the reference voltage.

[0020] In any of the above-mentioned circuit devices, the second power supply voltage generating unit may be a step-down circuit that generates the second power supply voltage by stepping down the first power supply voltage with reference to the first power supply voltage.

[0021] In any of the above circuit devices, a stop signal for stopping the power conversion operation may be input to the power conversion circuit. In any of the above circuit devices, the power conversion circuit may continue to output the state signal after receiving the stop signal.

[0022] In any of the above circuit devices, the state signal may be a signal indicating a state of temperature, current, and voltage of the power conversion circuit. In any of the above circuit devices, the state signal generation unit may generate the state signal.

[0023] In a second aspect of the present invention, a power conversion circuit is provided. The power conversion circuit may include an alarm signal generating unit that generates an alarm signal indicating whether the power conversion circuit is in a preset state. Any of the power conversion circuits may include a state signal generating unit that generates a state signal having an amplitude different from the alarm signal and indicating the state of the power conversion circuit.

[0024] Any of the above-mentioned power conversion circuits may include an output terminal for outputting an output signal obtained by superimposing the alarm signal and the state signal.

[0025] In any of the above power conversion circuits, the alarm signal generating unit can switch between a reference voltage and a first power supply voltage different from the reference voltage to be applied to the output terminal. In any of the above power conversion circuits, the state signal generating unit can switch between an intermediate voltage and the first power supply voltage to be applied to the output terminal, the intermediate voltage being closer to the first power supply voltage than the reference voltage.

[0026] Any of the above-mentioned power conversion circuits may include a reference wiring to which the reference voltage is applied. Any of the above-mentioned power conversion circuits may include a power supply wiring to which the first power supply voltage is applied. In any of the above-mentioned power conversion circuits, the state signal generating unit may include a first switch provided between the reference wiring and the power supply wiring. In any of the above-mentioned power conversion circuits, the state signal generating unit may include an intermediate voltage generating unit provided between the first switch and the reference wiring and generating the intermediate voltage.

[0027] In any of the above-mentioned power conversion circuits, the alarm signal generating unit may include a second switch that switches which of the reference voltage and the first power supply voltage is applied to the output terminal.

[0028] Any of the above-mentioned power conversion circuits may include an amplitude switching unit that switches which of the alarm signal and the state signal has an amplitude greater than the other.

[0029] In any of the above circuit devices, the state signal may be a signal indicating a state of temperature, current, and voltage of the power conversion circuit. In any of the above circuit devices, the state signal generation unit may generate the state signal.

[0030] The above invention summary does not list all the features of the present invention. In addition, sub-combinations of these feature groups can also constitute inventions. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a diagram showing an example of a circuit device 10 according to an embodiment of the present invention.

[0032] Figure 2 1 is a diagram showing a configuration example of a part of the power conversion circuit 200 and the transmission device 300 .

[0033] Figure 3 : is a timing chart showing an example of the output signal OS, the signal VM1, and the signal VM2.

[0034] Figure 4 2 is a diagram showing another configuration example of the transmission device 300 .

[0035] Figure 5 2 is a diagram showing another configuration example of the power conversion circuit 200 .

[0036] Figure 6 It is shown Figure 5 A timing diagram of an example of the output signal OS, the signal VM1, and the signal VM2 in the structure shown.

[0037] Figure 7 2 is a diagram showing another configuration example of the power conversion circuit 200 .

[0038] Explanation of symbols

[0039] 10…circuit device, 100…control circuit, 102…control output terminal, 106…status signal input terminal, 108…alarm input terminal, 200…power conversion circuit, 201…power supply wiring, 202…control terminal, 203…reference wiring, 204…output terminal, 206…power supply terminal, 208…reference voltage terminal, 210…status signal generating unit, 211…first current source, 212…first switch, 213…intermediate voltage generating unit, 214…amplitude switching switching unit, 220…alarm signal generating unit, 221…second current source, 222…second switch, 230…output resistor, 240…switch control unit, 300…transmission device, 310…first transmission unit, 311…first light emitting element, 321…first light receiving element, 320…second transmission unit, 321…second light emitting element, 322…second light receiving element, 330…first power supply voltage generating unit, 340…second power supply voltage generating unit, 342…step-down circuit, 344…resistance. DETAILED DESCRIPTION

[0040] Although the present invention is described below by the embodiments of the invention, the following embodiments do not limit the invention involved in the claims. In addition, all combinations of the features described in the embodiments are not necessarily necessary for the technical solution of the invention. It should be noted that in this specification and the drawings, for elements having substantially the same function and structure, repeated descriptions are omitted by marking the same symbols, and the illustrations of elements that are not directly related to the present invention are omitted. In addition, in one drawing, for elements having the same function and structure, symbols are representatively marked, and for others, symbols are sometimes omitted.

[0041] In this specification, when it is said that they are "same" or "equal", it may include the case where there is an error due to manufacturing variation, etc. The error is within 10%, for example.

[0042] Figure 1 1 is a diagram showing an example of a circuit device 10 according to an embodiment of the present invention. The circuit device 10 has one or more power conversion circuits 200 and a transmission device 300. The circuit device 10 may also have a control circuit 100. The transmission device 300 transmits signals between the power conversion circuit 200 and the control circuit 100. The transmission device 300 may be provided for each power conversion circuit 200. The power conversion circuit 200 may output power to other circuits of an object device provided with the circuit device 10. As an example, the control circuit 100 is a computer provided in the object device. The control circuit 100 may also control circuits other than the power conversion circuit 200 of the object device. As an example, the object device is an automobile or an industrial robot, etc., but is not limited thereto.

[0043] The power conversion circuit 200 converts input power into a predetermined output power. As an example, the power conversion circuit 200 is an ACDC converter that converts DC power into AC power, but the form of the power conversion circuit 200 is not limited to this. The power conversion circuit 200 may include power semiconductors such as IGBTs. The power conversion circuit 200 may include an inverter. The power conversion circuit 200 may supply power to an electric motor such as a motor.

[0044] The control circuit 100 controls the power conversion circuit 200. The control circuit 100 can control the on and off of the operation of the power conversion circuit 200, and can also control the amplitude or frequency of the power output by the power conversion circuit 200. The control circuit 100 of this example sends a control signal to each power conversion circuit 200. The control signal can control the switching of the transistor inside the power conversion circuit 200.

[0045] The power conversion circuit 200 has a control terminal 202 and an output terminal 204. A control signal from the control circuit 100 is input to the control terminal 202 via the transmission device 300. The output terminal 204 outputs an output signal to the control circuit 100. The output signal is transmitted by the transmission device 300.

[0046] The output signal includes an alarm signal and a state signal. The alarm signal is a signal indicating whether the power conversion circuit 200 has reached a preset state. The state may be an abnormal state such as an overcurrent state in which a current exceeding a predetermined value flows through a predetermined portion of the power conversion circuit 200, an overvoltage state in which a voltage exceeding a predetermined value is applied to a predetermined portion of the power conversion circuit 200, or an overheat state in which the temperature of a predetermined portion of the power conversion circuit 200 exceeds a predetermined value. The power conversion circuit 200 may change the pulse width of the alarm signal according to the type of abnormal state. Thus, the control circuit 100 can detect the type of abnormality generated in the power conversion circuit 200.

[0047] The state signal is a signal indicating the state of the power conversion circuit 200 at a predetermined position of the power conversion circuit 200. The state of the power conversion circuit 200 may be the state of one or more parameters of the temperature, current, and voltage of the position. The state signal may be a signal indicating the numerical value of the state of temperature, current, or voltage. The numerical value of the state of temperature, current, or voltage is indicated by the width of the pulse contained in the state signal. In another example, the numerical value of the state of temperature, current, or voltage may be indicated by the density of the pulse, etc. The numerical values ​​of multiple parameters may be indicated by different characteristics of the pulse. For example, the numerical value of one parameter of temperature, current, and voltage may be indicated by the width of the pulse, and the numerical value of another parameter may be indicated by the density of the pulse. The state signal may be generated according to a request from the control circuit 100, or may be generated according to a predetermined trigger. The output signal in this example includes a pulse of an alarm signal and a pulse of a state signal. By outputting the alarm signal and the state signal from a common output terminal 204, the number of terminals of the power conversion circuit 200 may be reduced.

[0048] The control circuit 100 of this example has a control output terminal 102, a state signal input terminal 106, and an alarm input terminal 108. The control output terminal 102 outputs a control signal. The state signal included in the output signal is input to the state signal input terminal 106. The alarm signal included in the output signal is input to the alarm input terminal 108. The transmission device 300 can extract the state signal and the alarm signal from the output signal and input them to the state signal input terminal 106 and the alarm input terminal 108. In another example, the control circuit 100 receives the output signal, and the control circuit 100 can extract the state signal and the alarm signal from the output signal.

[0049] When a plurality of power conversion circuits 200 are connected to a common terminal of the control circuit 100, an identification code may be assigned to each power conversion circuit 200. When the control circuit 100 starts communicating with any power conversion circuit 200, it may send a signal including the identification code of the power conversion circuit 200. When each power conversion circuit 200 receives a signal including an identification code corresponding to itself, it may operate according to the signal. The control circuit 100 may determine which power conversion circuit 200 the signal is from based on the identification information included in the signal output by the power conversion circuit 200.

[0050] The control circuit 100 may notify the start of communication to the power conversion circuit 200 by transmitting a clock signal. In another example, the control circuit 100 may notify the start of communication by the same method as that of I2C communication.

[0051] Figure 2 2 is a diagram showing a configuration example of a part of the power conversion circuit 200 and the transmission device 300. Figure 2 In FIG. 1 , a structure for outputting and transmitting an output signal is shown, and other structures are omitted.

[0052] The power conversion circuit 200 includes an alarm signal generating unit 220 for generating an alarm signal and a state signal generating unit 210 for generating a state signal. The state signal generating unit 210 generates a state signal having a pulse with an amplitude different from that of the alarm signal. By making the pulse amplitude of the alarm signal different from the pulse amplitude of the state signal, the pulse of the alarm signal and the pulse of the state signal can be distinguished from each other. The transmission device 300 can determine whether each pulse is a pulse of the alarm signal or a pulse of the state signal based on the amplitude of each pulse included in the output signal.

[0053] The power conversion circuit 200 of this example further includes a power supply terminal 206, a power supply wiring 201, a reference voltage terminal 208, and a reference wiring 203. The reference wiring 203 is connected to the reference voltage terminal 208. A reference voltage GND is applied to the reference voltage terminal 208 and the reference wiring 203. The reference voltage GND is, for example, 0V. The power supply wiring 201 is connected to the power supply terminal 206. A first power supply voltage Vcc1 different from the reference voltage GND is applied to the power supply terminal 206 and the power supply wiring 201. The first power supply voltage Vcc1 may be a voltage higher than the reference voltage GND. As an example, the first power supply voltage Vcc1 is 15V. The alarm signal generating unit 220 and the state signal generating unit 210 are arranged side by side with each other between the power supply wiring 201 and the reference wiring 203.

[0054] The alarm signal generating unit 220 of this example switches between the reference voltage GND and the first power supply voltage Vcc1 to be applied to the output terminal 204. For example, the alarm signal generating unit 220 applies the reference voltage GND to the output terminal 204 during a period in which a pulse of an alarm signal should be generated, and applies the first power supply voltage Vcc1 to the output terminal 204 during another period.

[0055] The alarm signal generating unit 220 of this example includes a second switch 222. The second switch 222 is provided between the power wiring 201 and the reference wiring 203, and switches which of the reference voltage GND and the first power supply voltage Vcc1 is applied to the output terminal 204. If the second switch 222 is turned on, the reference voltage GND is applied to the output terminal 204, and if the second switch 222 is turned off, the first power supply voltage Vcc1 is applied to the output terminal 204. The second switch 222 is, for example, a MOS transistor. In this example, the source terminal of the second switch 222 is connected to the reference wiring 203, and the drain terminal is connected to the power wiring 201 and the output terminal 204. A second current source 221 described later may be provided between the drain terminal and the power wiring 201. An output resistor 230 described later may be provided between the drain terminal and the output terminal 204.

[0056] The power conversion circuit 200 may include a switch control unit 240 that controls the second switch 222. The switch control unit 240 may generate a gate signal applied to a gate terminal of the second switch 222. The switch control unit 240 may turn on the second switch 222 during a pulse period for which an alarm signal should be generated, and turn off the second switch 222 during another period.

[0057] The alarm signal generating unit 220 may further include a second current source 221. The second current source 221 is provided between the power supply wiring 201 and the second switch 222. The second current source 221 allows a current to flow in a direction from the power supply wiring 201 toward the second switch 222. A connection point between the second current source 221 and the second switch 222 is connected to the output terminal 204. An output resistor 230 may be provided between a connection point between the second current source 221 and the second switch 222 and the output terminal 204.

[0058] The state signal generating unit 210 of this example switches which of the intermediate voltage Vm and the first power supply voltage Vcc1 is applied to the output terminal 204. The intermediate voltage Vm is closer to the first power supply voltage Vcc1 than the reference voltage GND. For example, the state signal generating unit 210 applies the intermediate voltage Vm to the output terminal 204 during the period when the pulse of the state signal should be generated, and applies the first power supply voltage Vcc1 to the output terminal 204 during another period. The intermediate voltage Vm can be greater than half of the first power supply voltage Vcc1. As an example, the intermediate voltage Vm is 10V.

[0059] The state signal generating section 210 of this example includes a first switch 212 and an intermediate voltage generating section 213. The first switch 212 is provided between the reference wiring 203 and the power supply wiring 201. The intermediate voltage generating section 213 is provided between the first switch 212 and the reference wiring 203.

[0060] The intermediate voltage generating unit 213 generates the intermediate voltage Vm. The intermediate voltage generating unit 213 of this example includes a Zener diode having an anode connected to the reference wiring 203 and a cathode connected to the first switch 212. The intermediate voltage Vm is generated by the breakdown voltage of the Zener diode.

[0061] The first switch 212 switches between the intermediate voltage Vm and the first power supply voltage Vcc1 to be applied to the output terminal 204. If the first switch 212 is turned on, the intermediate voltage Vm is applied to the output terminal 204, and if the first switch 212 is turned off, the first power supply voltage Vcc1 is applied to the output terminal 204. The first switch 212 is, for example, a MOS transistor. In this example, the source terminal of the first switch 212 is connected to the intermediate voltage generating unit 213, and the drain terminal is connected to the power supply wiring 201 and the output terminal 204. A first current source 211 described later may be provided between the drain terminal and the power supply wiring 201. An output resistor 230 may be provided between the drain terminal and the output terminal 204.

[0062] The switch control unit 240 may control the first switch 212. The switch control unit 240 may generate a gate signal applied to a gate terminal of the first switch 212. The switch control unit 240 may turn on the first switch 212 during a period of a pulse for generating a state signal, and turn off the first switch 212 during another period.

[0063] The state signal generating unit 210 may further include a first current source 211. The first current source 211 is provided between the power supply wiring 201 and the first switch 212. The first current source 211 allows current to flow in a direction from the power supply wiring 201 toward the first switch 212. The connection point between the first current source 211 and the first switch 212 is connected to the output terminal 204. An output resistor 230 may also be provided between the connection point between the first current source 211 and the first switch 212 and the output terminal 204. The output resistor 230 of this example is provided in common for the alarm signal generating unit 220 and the state signal generating unit 210.

[0064] The output signal OS obtained by overlapping the alarm signal and the state signal is applied to the output terminal 204 of this example. The output signal OS includes a pulse of the alarm signal and a pulse of the state signal. The amplitude of the pulse of the alarm signal is different from that of the pulse of the state signal. During the period when the pulse of the alarm signal overlaps with the pulse of the state signal, a pulse with a larger amplitude (in this example, the pulse of the alarm signal) is configured in the output signal OS.

[0065] The transmission device 300 of this example includes a first transmission unit 310 and a second transmission unit 320. Both the first transmission unit 310 and the second transmission unit 320 are connected to the output terminal 204 and receive the output signal OS.

[0066] The first transmission unit 310 of this example generates a signal VM1, which is a signal obtained by extracting a component (a pulse in this example) having an amplitude greater than a first reference value from the output signal OS. The second transmission unit 320 of this example generates a signal VM2, which is a signal obtained by extracting a component having an amplitude greater than a second reference value from the output signal OS. In this example, the first reference value in the first transmission unit 310 is smaller than the second reference value in the second transmission unit 320.

[0067] The amplitude of one of the pulses of the state signal and the pulse of the alarm signal is greater than the first reference value and less than the second reference value. The pulse is extracted in the first transmission unit 310, but not in the second transmission unit 320. The amplitude of the other of the pulses of the state signal and the pulse of the alarm signal is greater than the second reference value. The pulse is extracted by both the first transmission unit 310 and the second transmission unit 320.

[0068] exist Figure 2 In the example of , the amplitude of the pulse of the state signal is greater than the first reference value and less than the second reference value. In addition, the amplitude of the pulse of the alarm signal is greater than the second reference value. In this case, the signal VM1 generated by the first transmission unit 310 includes both the pulse of the state signal and the pulse of the alarm signal. The signal VM2 generated by the second transmission unit 320 does not include the pulse of the state signal, but includes the pulse of the alarm signal.

[0069] Figure 2 The second transmission unit 320 of the example inputs a signal VM2 to the alarm input terminal 108 of the control circuit 100. When the control circuit 100 detects a pulse including an alarm signal in the signal VM2, it can input a stop signal for stopping the power conversion operation of the power conversion circuit 200 to the power conversion circuit 200. When the power conversion circuit 200 uses a switching element to perform power conversion, the control circuit 100 can stop the switching operation of the switching element.

[0070] The power conversion circuit 200 may further stop outputting the status signal when a stop signal is input. In another example, the power conversion circuit 200 may continue to output the status signal even after a stop signal is input. Thus, the control circuit 100 can detect the temperature, voltage, or current of the power conversion circuit 200 even after the power conversion operation of the power conversion circuit 200 is stopped. In the case where the power conversion operation of the power conversion circuit 200 is stopped based on an alarm signal indicating that the power conversion circuit 200 is in an overheated state, the control circuit 100 may restart the power conversion operation of the power conversion circuit 200 when the temperature of the power conversion circuit 200 is below a set value. In the case where the power conversion operation of the power conversion circuit 200 is stopped based on an alarm signal indicating that the power conversion circuit 200 is in an overvoltage or overcurrent state, the control circuit 100 may restart the power conversion operation of the power conversion circuit 200 when the voltage or current of the power conversion circuit 200 is below a set value.

[0071] Figure 2 The first transmission unit 310 of the example inputs the signal VM1 to the state signal input terminal 106 of the control circuit 100. The control circuit 100 detects the state signal of the power conversion circuit 200 based on the pulse of the signal VM1. In this example, the pulse of the signal VM1 during the period when the pulse of the signal VM2 exists is not the pulse of the state signal. The control circuit 100 may not use the pulse of the signal VM1 during the period when the pulse of the signal VM2 exists for the detection of the state signal.

[0072] According to this example, the alarm signal and the status signal can be output from the common output terminal 204. In addition, in the transmission device 300, the alarm signal and the status signal can be extracted. During the period when the pulses of the alarm signal and the status signal overlap, the pulse of the alarm signal can be preferentially detected. As a result, the pulses of the alarm signal and the pulses of the status signal can be quickly identified, and the abnormality of the power conversion circuit 200 can be quickly detected.

[0073] The first transmission unit 310 of this example has a photocoupler. The first transmission unit 310 has a first light emitting element 311 such as a light emitting diode and a first light receiving element 312 such as a phototransistor. The second transmission unit 320 of this example has a photocoupler. The second transmission unit 320 has a second light emitting element 321 such as a light emitting diode and a second light receiving element 322 such as a phototransistor.

[0074] The transmission device 300 of this example further includes a first power supply voltage generating unit 330 generating a first power supply voltage Vcc1 based on the reference voltage GND and a second power supply voltage generating unit 340 generating a second power supply voltage Vcc2 based on the reference voltage GND. The second power supply voltage generating unit 340 of this example is a power supply that generates a second power supply voltage Vcc2 higher than the reference voltage.

[0075] The first power supply voltage Vcc1 is applied to the anode of the first light emitting element 311, and the output signal OS is applied to the cathode. The first light emitting element 311 emits light when the voltage between the anode and the cathode is equal to or higher than the reference value. The first light receiving element 312 becomes conductive in response to the light emission of the first light emitting element 311, and makes the voltage of the signal VM1 become L level (for example, 0V). When the first light receiving element 312 is in the off state, the voltage of the signal VM1 becomes a predetermined H level higher than 0V.

[0076] The second power supply voltage Vcc2 is applied to the anode of the second light emitting element 321, and the output signal OS is applied to the cathode. The second light emitting element 321 emits light when the voltage between the anode and the cathode is greater than the reference value. The second light receiving element 322 becomes conductive in response to the light emission of the second light emitting element 321, and makes the voltage of the signal VM2 an L level (for example, 0V). When the second light receiving element 322 is in the off state, the voltage of the signal VM2 becomes a predetermined H level higher than 0V.

[0077] Figure 3 : is a timing diagram showing an example of output signal OS, signal VM1 and signal VM2. In this example, output signal OS includes pulses of state signal and pulses of alarm signal. The pulse of state signal has an amplitude from first power supply voltage Vcc1 to intermediate voltage Vm. The pulse of alarm signal has an amplitude from first power supply voltage Vcc1 to reference voltage GND. Second power supply voltage Vcc2 is a voltage between reference voltage GND and intermediate voltage Vm. As an example, first power supply voltage Vcc1 is 15V, intermediate voltage Vm is 10V, second power supply voltage Vcc2 is 5V, and reference voltage GND is 0V.

[0078] Figure 2The first transmission unit 310 shown outputs a signal VM1 corresponding to the difference between the first power supply voltage Vcc1 and the voltage of the output signal OS. When the voltage of the difference is greater than the first threshold voltage for causing the first light-emitting element 311 to emit light, a pulse is configured in the signal VM1. The first threshold voltage of this example is less than the difference between the first power supply voltage Vcc1 and the intermediate voltage Vm. In addition, the first threshold voltage is less than the difference between the first power supply voltage Vcc1 and the reference voltage GND. Thus, a pulse is configured in the signal VM1 corresponding to both a pulse of the state signal and a pulse of the alarm signal. The control circuit 100 can detect the state signal based on the signal VM1.

[0079] Figure 2 The second transmission unit 320 shown outputs a signal VM2 corresponding to the difference between the second power supply voltage Vcc2 and the voltage of the output signal OS. When the voltage of the difference is greater than the second threshold voltage for causing the second light-emitting element 321 to emit light, a pulse is configured in the signal VM2. The second threshold voltage in this example is less than the difference between the second power supply voltage Vcc2 and the reference voltage GND. Thus, a pulse is configured in the signal VM2 corresponding to the pulse of the alarm signal. In addition, the L-level intermediate voltage Vm in the pulse of the status signal is higher than the second power supply voltage Vcc2. In this case, a reverse voltage is applied to the second light-emitting element 321, and the second light-emitting element 321 does not emit light. Therefore, a pulse corresponding to the pulse of the status signal is not configured in the signal VM2. The control circuit 100 can detect the alarm signal based on the signal VM2.

[0080] The pulse widths tT1 and tT2 of the status signal can represent the value of the temperature, voltage or current of the power conversion circuit 200. For example, the larger the pulse width, the higher the temperature, voltage or current. In addition, each pulse width tA1, tA2, tA3 of the alarm signal corresponds to a certain abnormal state generated in the power conversion circuit 200. In the case that multiple abnormalities occur in the power conversion circuit 200, the power conversion circuit 200 can be as follows Figure 3 As shown, an output signal having multiple pulses corresponding to multiple abnormal states is generated.

[0081] Figure 4 1 is a diagram showing another configuration example of the transmission device 300. The transmission device 300 of this example includes a step-down circuit 342 that functions as a second power supply voltage generating unit 340. Figure 2 The examples shown are the same.

[0082] The step-down circuit 342 generates a second power supply voltage Vcc2 by stepping down the first power supply voltage Vcc1 with the first power supply voltage Vcc1 as a reference. The step-down circuit 342 may include a Zener diode having a cathode connected to the power supply terminal 206 and an anode connected to the reference voltage terminal 208. The anode of the Zener diode is connected to the anode of the second light emitting element 321. The second power supply voltage Vcc2 that is stepped down from the first power supply voltage Vcc1 is generated by the breakdown voltage of the Zener diode.

[0083] As in Figure 3 As described in , the second power supply voltage Vcc2 is a voltage between the intermediate voltage Vm and the reference voltage GND. That is, the voltage (Vcc1-Vcc2) stepped down by the step-down circuit 342 is greater than the difference (Vcc1-Vm) between the first power supply voltage Vcc1 and the intermediate voltage Vm.

[0084] The transmission device 300 may further include a resistor 344. The resistor 344 is disposed between the connection point between the step-down circuit 342 and the second light emitting element 321 and the reference voltage terminal 208. Figures 1 to 3 Similarly to the example of , the pulse of the alarm signal and the pulse of the status signal can be quickly identified. The step-down circuit 342 may be a circuit other than a Zener diode. For example, a regulator circuit may be used as the step-down circuit 342.

[0085] Figure 5 2 is a diagram showing another configuration example of the power conversion circuit 200. In this example, the intermediate voltage generating unit 213 is not provided in the state signal generating unit 210, but is provided in the alarm signal generating unit 220. Figure 2 The intermediate voltage generating unit 213 of this example is provided between the second switch 222 and the reference wiring 203. In this example, the anode of the intermediate voltage generating unit 213 is connected to the reference wiring 203, and the cathode of the intermediate voltage generating unit 213 is connected to the source of the second switch 222.

[0086] In this example, the amplitude of the pulse of the alarm signal is smaller than the amplitude of the pulse of the status signal. In this example, the first transmission unit 310 also generates a signal VM1, which is a signal obtained by extracting a component (in this example, a pulse) with an amplitude greater than a first reference value in the output signal OS. The second transmission unit 320 generates a signal VM2, which is a signal obtained by extracting a component with an amplitude greater than a second reference value in the output signal OS. The first reference value in the first transmission unit 310 is smaller than the second reference value in the second transmission unit 320.

[0087] In this example, the amplitude of the pulse of the alarm signal is greater than the first reference value and less than the second reference value. In addition, the amplitude of the pulse of the state signal is greater than the second reference value. In this case, the signal VM2 generated by the second transmission unit 320 includes both the pulse of the state signal and the pulse of the alarm signal. The signal VM1 generated by the first transmission unit 310 includes the pulse of the state signal but does not include the pulse of the alarm signal.

[0088] Figure 6 It is shown Figure 5 A timing diagram of an example of output signals OS, VM1 and VM2 in the structure shown. The pulse of the state signal in this example has an amplitude from the first power supply voltage Vcc1 to the reference voltage GND. The pulse of the alarm signal has an amplitude from the first power supply voltage Vcc1 to the intermediate voltage Vm.

[0089] In this example, a pulse is arranged in the signal VM1 in correspondence with both a pulse of the state signal and a pulse of the alarm signal, and a pulse is arranged in the signal VM2 in correspondence with a pulse of the state signal.

[0090] The control circuit 100 can detect the state of the power conversion circuit 200 based on the pulse widths tT1 and tT2 of the signal VM2. The control circuit 100 detects the alarm signal of the power conversion circuit 200 based on the pulse of the signal VM1. In this example, the pulse of the signal VM1 during the period when the pulse exists in the signal VM2 is not the pulse of the alarm signal. The control circuit 100 may not use the pulse of the signal VM1 during the period when the pulse exists in the signal VM2 for the detection of the alarm signal.

[0091] According to this example, the alarm signal and the status signal can be output from the common output terminal 204. In addition, the alarm signal and the status signal can be extracted in the transmission device 300. During the period when the pulses of the alarm signal and the status signal overlap, the pulse of the status signal can be preferentially detected. Thus, the temperature, voltage or current of the power conversion circuit 200 can be easily detected.

[0092] Figure 7 FIG. 2 is a diagram showing another configuration example of the power conversion circuit 200. Figure 2 or Figure 5 In addition to the structure shown in FIG. 1 , the power conversion circuit 200 of this example further includes an amplitude switching unit 214. The intermediate voltage generating unit 213 can be provided inside the amplitude switching unit 214. Figure 7 In the embodiment, the switch control unit 240 is omitted. Figure 2 or Figure 5 Same as the example.

[0093] The amplitude switching unit 214 is used to make the power conversion circuit 200 Figure 2 The examples and Figure 5 The amplitude switching unit 214 switches the function according to which of the examples described in the above is used. That is, the amplitude switching unit 214 switches which of the alarm signal and the state signal has an amplitude larger than the other. The amplitude switching unit 214 can switch which of the alarm signal and the state signal has an amplitude larger than the second reference value, or which of the alarm signal and the state signal has an amplitude larger than the first reference value and smaller than the second reference value.

[0094] The amplitude switching unit 214 can be used to switch the intermediate voltage generating unit 213 to Figure 5 connected to the alarm signal generating unit 220 as shown, or as Figure 2 As shown in FIG. 1 , the intermediate voltage generator 213 is connected to the state signal generator 210 and switched. The amplitude switch 214 may include a switch for switching whether the intermediate voltage generator 213 is connected to the alarm signal generator 220 or to the state signal generator 210 .

[0095] The amplitude switching section 214 may include a first path including the intermediate voltage generating section 213 and a second path not including the intermediate voltage generating section 213. The switching switch may select one of the first switch 212 and the second switch 222 and connect it to the reference wiring 203 via the first path, and may select the other of the first switch 212 and the second switch 222 and connect it to the reference wiring 203 via the second path.

[0096] According to this example, the power conversion circuit 200 can be used as Figure 2 Examples and Figure 5 The example in which the power conversion circuit 200 functions may be set by the user of the power conversion circuit 200, may be set by the manufacturer of the power conversion circuit 200, or may be controlled by the control circuit 100 or other devices. Information on which example the power conversion circuit 200 functions may be notified to the control circuit 100. The amplitude switching unit 214 may notify the control circuit 100 of the information.

[0097] The control circuit 100 can determine whether the pulse of the signal VM2 is a pulse of an alarm signal or a pulse of a status signal based on which example the power conversion circuit 200 functions as. The control circuit 100 can determine whether the pulse of the signal VM1 that does not overlap with the pulse of the signal VM2 is a pulse of an alarm signal or a pulse of a status signal based on which example the power conversion circuit 200 functions as.

[0098] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. According to the description of the claims, the method to which such changes or improvements are made is also included in the technical scope of the present invention.

Claims

1. A circuit device, characterized in that: have: power conversion circuit; and a transmission device for transmitting a signal from the power conversion circuit, The power conversion circuit has: an alarm signal generating unit configured to generate an alarm signal indicating whether the power conversion circuit has reached a preset state; as well as A state signal generating unit generates a state signal having an amplitude different from that of the alarm signal and indicating a state of the power conversion circuit.

2. The circuit arrangement according to claim 1, characterized in that The power conversion circuit further includes an output terminal configured to output an output signal in which the alarm signal and the state signal are superimposed.

3. The circuit arrangement according to claim 2, characterized in that The alarm signal generating unit switches whether to apply a reference voltage or a first power supply voltage different from the reference voltage to the output terminal. The state signal generating unit switches which of an intermediate voltage and the first power supply voltage is applied to the output terminal, the intermediate voltage being closer to the first power supply voltage than the reference voltage.

4. The circuit arrangement according to claim 3, characterized in that The power conversion circuit has: a reference wiring to which the reference voltage is applied; and a power supply wiring to which the first power supply voltage is applied, The state signal generating unit comprises: a first switch provided between the reference wiring and the power supply wiring; as well as An intermediate voltage generating unit is provided between the first switch and the reference wiring and generates the intermediate voltage.

5. The circuit arrangement according to claim 4, characterized in that The alarm signal generating unit includes a second switch configured to switch between the reference voltage and the first power supply voltage to be applied to the output terminal.

6. The circuit arrangement according to claim 2, characterized in that The transmission device comprises: A first transmission unit that transmits a component of the output signal having an amplitude greater than a first reference value; and a second transmission unit for transmitting a component of the output signal having an amplitude greater than a second reference value; The first reference value is smaller than the second reference value.

7. The circuit arrangement according to claim 6, characterized in that The amplitude of the state signal is greater than the first reference value and less than the second reference value, The amplitude of the alarm signal is greater than the second reference value.

8. The circuit arrangement according to claim 6, characterized in that the amplitude of the state signal is greater than the second reference value, The amplitude of the alarm signal is greater than the first reference value and less than the second reference value.

9. The circuit arrangement according to claim 6, characterized in that The power conversion circuit further includes an amplitude switching unit that switches which of the alarm signal and the state signal has an amplitude greater than the second reference value and which has an amplitude greater than the first reference value and less than the second reference value.

10. The circuit arrangement according to claim 3, characterized in that The transmission device comprises: a second power supply voltage generating unit for generating a second power supply voltage between the reference voltage and the intermediate voltage; a first transmission section that outputs a signal corresponding to a difference between the first power supply voltage and a voltage of the output terminal; as well as A second transmission section outputs a signal corresponding to a difference between the second power supply voltage and a voltage of the output terminal.

11. The circuit arrangement according to claim 10, characterized in that The second power supply voltage generating unit is a power supply that generates the second power supply voltage based on the reference voltage, and the second power supply voltage is higher than the reference voltage.

12. The circuit arrangement according to claim 10, characterized in that The second power supply voltage generating unit is a step-down circuit that generates the second power supply voltage by stepping down the first power supply voltage with reference to the first power supply voltage.

13. The circuit arrangement according to claim 1, characterized in that inputting a stop signal to the power conversion circuit to stop the power conversion operation, The power conversion circuit continues to output the state signal after the stop signal is input.

14. The circuit arrangement according to any one of claims 1 to 13, characterized in that The state signal is a signal indicating a state of one of temperature, current, and voltage of the power conversion circuit, and the state signal generating unit generates the state signal.

15. A power conversion circuit, characterized in that: have: an alarm signal generating unit configured to generate an alarm signal indicating whether the power conversion circuit is in a preset state; and A state signal generating unit generates a state signal having an amplitude different from that of the alarm signal and indicating a state of the power conversion circuit.

16. The power conversion circuit according to claim 15, characterized in that: The power conversion circuit further includes an output terminal configured to output an output signal in which the alarm signal and the state signal are superimposed.

17. The power conversion circuit according to claim 16, characterized in that: The alarm signal generating unit switches whether to apply a reference voltage or a first power supply voltage different from the reference voltage to the output terminal. The state signal generating unit switches which of an intermediate voltage and the first power supply voltage is applied to the output terminal, the intermediate voltage being closer to the first power supply voltage than the reference voltage.

18. The power conversion circuit according to claim 17, characterized in that: The power conversion circuit further comprises: a reference wiring to which the reference voltage is applied; and a power supply wiring to which the first power supply voltage is applied, The state signal generating unit comprises: a first switch provided between the reference wiring and the power supply wiring; as well as An intermediate voltage generating unit is provided between the first switch and the reference wiring and generates the intermediate voltage.

19. The power conversion circuit according to claim 18, characterized in that: The alarm signal generating unit includes a second switch configured to switch between the reference voltage and the first power supply voltage to be applied to the output terminal.

20. The power conversion circuit according to claim 16, characterized in that: The power conversion circuit further includes an amplitude switching unit configured to switch which of the alarm signal and the state signal has an amplitude greater than the other.

21. The power conversion circuit according to any one of claims 15 to 20, characterized in that: The state signal is a signal indicating a state of one of temperature, current, and voltage of the power conversion circuit, and the state signal generating unit generates the state signal.

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