Widebandgap photorelay

Abstract

To provide a wide-band gap photo relay capable of improving an off-state voltage and a switching speed.SOLUTION: A wide-band gap photo relay comprises: first and second input terminals; first and second output terminals; a ground terminal; a light source; a photodiode array; and a depletion type wide-band gap semiconductor switch. The light source generates a light signal, includes a first end and a second end that are connected to the first and second input terminals. The photodiode array is installed so as to be separated from the light source, and includes a positive terminal and a negative terminal. The photodiode array generates a voltage difference between the positive terminal and the negative terminal when detecting the light signal. The positive terminal is connected to the ground terminal, and the depression type wide-band gap semiconductor switch includes: a gate electrode connected to the negative terminal; a drain electrode connected to the first output terminal; and a source electrode connected to the second output terminal.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wide-bandgap photorelay, and more particularly to a wide-bandgap photorelay equipped with a depletion-type wide-bandgap semiconductor switch. [Background technology]

[0002] In recent years, photorelays have been widely used in consumer electronics, automation and control systems, communication systems, electric vehicles, and other applications.

[0003] A photorelay drives a light-emitting diode (LED) at a low voltage to generate an optical signal, which controls the switching of a semiconductor switch on the high-voltage load side. However, the off-state voltage and switching speed of the semiconductor switch in conventional photorelays are limited by material properties, making it difficult to achieve significant improvements.

[0004] In light of the above circumstances, improving the reliability and durability of photorelays by increasing the off-state voltage of semiconductor switches and shortening the switching time, thereby meeting the needs of various applications, has become an urgent issue for the industry. [Overview of the project]

[0005] The objective of the present invention is to provide a wide-bandgap photorelay with improved off-state voltage and switching speed using a depletion-type wide-bandgap semiconductor switch. Compared to conventional photorelays, the wide-bandgap photorelay of the present invention has characteristics such as high voltage resistance, high-speed switching, high reliability, and high durability, and can meet the needs of various applications.

[0006] To achieve the above objective, the present invention provides a wide bandgap photorelay. The wide bandgap photorelay comprises a first input terminal, a second input terminal, a first output terminal, a second output terminal, a ground terminal, a light source that generates an optical signal and has a first terminal connected to the first input terminal and a second terminal connected to the second input terminal, a photodiode array installed separately from the light source and having a positive terminal and a negative terminal, which generates a voltage difference between the positive terminal and the negative terminal when it detects the optical signal, and whose positive terminal is connected to the ground terminal, and a depletion-type wide bandgap semiconductor switch having a gate electrode connected to the negative terminal, a drain electrode connected to the first output terminal, and a source electrode connected to the second output terminal.

[0007] In embodiments of the present invention, the light source is a gallium arsenide (GaAs) light-emitting diode (LED).

[0008] In an embodiment of the present invention, the photodiode array includes a plurality of silicon photodiodes connected in series in an array.

[0009] In an embodiment of the present invention, the wide-bandgap photorelay further comprises a control circuit connected between the photodiode array and the depletion-type wide-bandgap semiconductor switch.

[0010] In embodiments of the present invention, the depletion-type wide-bandgap semiconductor switch is a depletion-type gallium nitride (GaN) high-electron mobility transistor (HEMT) or a silicon carbide junction field-effect transistor (JFET).

[0011] In an embodiment of the present invention, the light source and the photodiode array are arranged laterally relative to each other.

[0012] In an embodiment of the present invention, the light source and the photodiode array are arranged vertically relative to each other.

[0013] In an embodiment of the present invention, the wide bandgap photorelay further comprises a diode, the anode of which is connected to the source electrode, and the cathode of which is connected to the drain electrode.

[0014] The present invention provides a wide-bandgap photorelay. The wide-bandgap photorelay comprises a first input terminal, a second input terminal, a first output terminal, a second output terminal, a ground terminal, a light source that generates an optical signal and has a first terminal connected to the first input terminal and a second terminal connected to the second input terminal, a photodiode array installed separately from the light source, having a positive terminal and a negative terminal, which generates a voltage difference between the positive terminal and the negative terminal when it senses the optical signal, and whose positive terminal is connected to the ground terminal, and a pair of depletion-type wide-bandgap semiconductor switches. The pair of depletion-type wide-bandgap semiconductor switches comprises a first depletion-type wide-bandgap semiconductor switch and a second depletion-type wide-bandgap semiconductor switch. The first depletion-type wide-bandgap semiconductor switch has a first source electrode, a first drain electrode, and a first gate electrode. The first gate electrode is connected to the negative terminal. The first drain electrode is connected to the first output terminal. The second depletion-type wide-bandgap semiconductor switch has a second source electrode, a second drain electrode, and a second gate electrode. The second gate electrode is connected to the negative terminal. The second source electrode is connected to the first source electrode. The second drain electrode is connected to the second output terminal.

[0015] In embodiments of the present invention, the light source is a gallium arsenide (GaAs) light-emitting diode (LED).

[0016] In an embodiment of the present invention, the photodiode array includes a plurality of silicon photodiodes connected in series in an array form.

[0017] In an embodiment of the present invention, the wide-bandgap photo relay further includes a control circuit connected between the photodiode array and the depletion-type wide-bandgap semiconductor switch pair.

[0018] In an embodiment of the present invention, the first depletion-type wide-bandgap semiconductor switch and the second depletion-type wide-bandgap semiconductor switch are depletion-type gallium nitride (GaN) high electron mobility transistors (High Electron Mobility Transistor, HEMT) or silicon carbide (SiC) junction field effect transistors (Junction Field-Effect Transistor, JFET).

[0019] In an embodiment of the present invention, the light source and the photodiode array are arranged laterally with respect to each other.

[0020] In an embodiment of the present invention, the light source and the photodiode array are arranged longitudinally with respect to each other.

[0021] In an embodiment of the present invention, the wide-bandgap photo relay further includes a first diode and a second diode. The anode of the first diode is connected to the first source electrode, the cathode of the first diode is connected to the first drain electrode, the anode of the second diode is connected to the second source electrode, and the cathode of the second diode is connected to the second drain electrode.

[0022] Those skilled in the art can understand other objects of the present invention, as well as the technical means and embodiments of the present invention, by referring to the drawings and the embodiments described below.

Brief Description of the Drawings

[0023] [Figure 1] Circuit diagram of widebandgap photorelay 1 according to an embodiment of the present invention [Figure 2A] Circuit diagram of widebandgap photorelay 2 according to an embodiment of the present invention [Figure 2B] Schematic diagram of control circuit 21 according to an embodiment of the present invention [Figure 3] Circuit diagram of the wide bandgap photorelay 3 according to an embodiment of the present invention [Figure 4] Circuit diagram of the wide bandgap photorelay 4 according to an embodiment of the present invention [Figure 5] Circuit diagram of the wide bandgap photorelay 5 according to an embodiment of the present invention [Figure 6] Circuit diagram of the wide bandgap photorelay 6 according to an embodiment of the present invention [Figure 7] Timing chart showing the state of each component during operation of a wide bandgap photorelay according to an embodiment of the present invention. [Modes for carrying out the invention]

[0024] The present invention will be described below through examples. These examples illustrate the embodiments of the present invention and are not intended to limit the invention to any particular environment, application, or specific configuration described therein. Therefore, while the examples illustrate the present invention, they do not limit it. Components not directly related to the present invention are omitted and not shown in the embodiments and drawings. The dimensional relationships of the components in the drawings are for ease of understanding and do not limit the actual dimensions.

[0025] Figure 1 is a circuit diagram showing a wide-bandgap photorelay 1 according to an embodiment of the present invention. The wide-bandgap photorelay 1 comprises a first input terminal IT1, a second input terminal IT2, a first output terminal OT1, a second output terminal OT2, a ground terminal GT, a light source 11, a photodiode array 13, and a depletion-type wide-bandgap semiconductor switch 15.

[0026] The light source 11 generates an optical signal and has a first terminal 111 and a second terminal 112. The first terminal 111 is connected to a first input terminal IT1. The second terminal 112 is connected to a second input terminal IT2. The light source 11 is a gallium arsenide (GaAs) light-emitting diode (LED) that generates infrared light with a wavelength of 840 nm to 920 nm, but is not limited to this. By inputting voltage from the first input terminal IT1 and the second input terminal IT2, the light source 11 can generate an optical signal.

[0027] The photodiode array 13 is installed separately from the light source 11. The photodiode array 13 has a positive terminal 131 and a negative terminal 132. When the photodiode array 13 detects an optical signal from the light source 11, it generates a voltage difference between the positive terminal 131 and the negative terminal 132. The positive terminal 131 of the photodiode array 13 is connected to the ground terminal GT. The photodiode array 13 contains multiple silicon photodiodes. The multiple silicon photodiodes are connected in series in an array, but are not limited to this configuration. The voltage difference between the positive terminal 131 and the negative terminal 132 of the photodiode array 13 is, for example, 10V to 25V. The voltage difference depends on the number of silicon photodiodes connected in series.

[0028] The depletion-type wide-bandgap semiconductor switch 15 has a source electrode, a drain electrode, and a gate electrode. The gate electrode is connected to the negative terminal 132 of the photodiode array 13. The drain electrode is connected to the first output terminal OT1. The source electrode is connected to the second output terminal OT2. When the photodiode array 13 detects an optical signal and a voltage difference occurs between the positive terminal 131 and the negative terminal 132, the voltage at the gate electrode of the depletion-type wide-bandgap semiconductor switch 15 becomes a negative voltage smaller than the threshold voltage (which is a negative voltage) of the depletion-type wide-bandgap semiconductor switch 15. As a result, the depletion-type wide-bandgap semiconductor switch 15 is in the off state (i.e., non-conductive). Conversely, when the photodiode array 13 does not detect an optical signal, the voltage at the gate electrode of the depletion-type wide-bandgap semiconductor switch 15 becomes 0. As a result, the depletion-type wide-bandgap semiconductor switch 15 is in the on state (i.e., conductive).

[0029] The depletion-type wide-bandgap semiconductor switch 15 is a semiconductor switch with a high breakdown field strength and a high saturation electron drift rate. For example, the depletion-type wide-bandgap semiconductor switch 15 is a depletion-type gallium nitride (GaN) high-electron mobility transistor (HEMT) or a silicon carbide (SiC) junction field-effect transistor (JFET). A depletion-type gallium nitride high-electron mobility transistor, for example, has a breakdown field strength of 3.3 MV / cm and a saturation electron drift rate of 2.5 × 10⁻¹⁰ 7 The value is cm / s. A silicon carbide junction field-effect transistor, for example, has a breakdown field strength of 3.5 MV / cm and a saturation electron drift rate of 2.0 × 10⁻⁶. 7 It is cm / s.

[0030] As described above, the depletion-type wide-bandgap semiconductor switch 15 of the present invention connects the gate electrode to the negative terminal 132 of the photodiode array 13. A voltage difference is generated between the positive terminal 131 and the negative terminal 132 depending on whether the photodiode array 13 detects an optical signal from the light source 11. In this way, the depletion-type wide-bandgap semiconductor switch 15 can be quickly switched on and off. Specifically, while the response time of an enhanced-type wide-bandgap semiconductor switch is about 5 ns to 50 ns, the response time of the depletion-type wide-bandgap semiconductor switch 15 is short, about 1 ns to 20 ns, making it suitable for applications requiring high-speed switching.

[0031] In practice, the light source 11 and the photodiode array 13 are arranged laterally spaced apart on the package substrate (i.e., arranged laterally (left and right)). By optical path design (e.g., by placing a reflective coating containing silver, aluminum, polyethylene terephthalate (Mylar), or mica on top), the photodiode array 13 can receive reflected light from the optical signal of the light source 11. In other embodiments, however, the light source 11 and the photodiode array 13 may be arranged vertically spaced apart on different package substrates (i.e., arranged vertically (up and down)). The photodiode array 13 receives direct light from the optical signal of the light source 11. As described above, the positional relationship between the light source 11 and the photodiode array 13 can be changed by optical path design, and various positional relationships are covered within the scope of the present invention.

[0032] Figure 2A is a circuit diagram of a wide-bandgap photorelay 2 according to an embodiment of the present invention. Unlike the wide-bandgap photorelay 1, the wide-bandgap photorelay 2 further includes a control circuit 21. The control circuit 21 is connected between the photodiode array 13 and the depletion-type wide-bandgap semiconductor switch 15. The control circuit 21 can further increase the switching speed. For example, as shown in Figure 2B, the control circuit 21 includes a transistor, two resistors, and a diode, but the present invention is not limited to this circuit configuration.

[0033] Figure 3 is a circuit diagram showing a wide-bandgap photorelay 3 according to an embodiment of the present invention. Unlike the wide-bandgap photorelay 1, the wide-bandgap photorelay 3 further includes a diode 31. As shown in Figure 3, the anode of the diode 31 is connected to the source electrode of the depletion-type wide-bandgap semiconductor switch 15. The cathode of the diode 31 is connected to the drain electrode of the depletion-type wide-bandgap semiconductor switch 15. In this way, the depletion-type wide-bandgap semiconductor switch 15 further has, for example, reverse bias protection and overvoltage protection to ensure that the depletion-type wide-bandgap semiconductor switch 15 operates with the correct polarity.

[0034] Furthermore, in one embodiment, the wide-bandgap photorelay according to the present invention may include a control circuit 21 and a diode 31. That is, it is a combination of a wide-bandgap photorelay 2 and a wide-bandgap photorelay 3.

[0035] Figure 4 is a circuit diagram showing a wide-bandgap photorelay 4 according to an embodiment of the present invention. The wide-bandgap photorelay 4 comprises a first input terminal IT1, a second input terminal IT2, a first output terminal OT1, a second output terminal OT2, a ground terminal GT, a light source 41, a photodiode array 43, and a pair of depletion-type wide-bandgap semiconductor switches (consisting of a first depletion-type wide-bandgap semiconductor switch 45 and a second depletion-type wide-bandgap semiconductor switch 47).

[0036] As described above, the light source 41 generates an optical signal and has a first terminal 411 and a second terminal 412. The first terminal 411 is connected to the first input terminal IT1. The second terminal 412 is connected to the second input terminal IT2. The light source 41 is a gallium arsenide (GaAs) light-emitting diode (LED), but is not limited to this. By inputting voltage from the first input terminal IT1 and the second input terminal IT2, the light source 41 can generate an optical signal.

[0037] The photodiode array 43 is installed separately from the light source 41. The photodiode array 43 has a positive terminal 431 and a negative terminal 432. The photodiode array 43 detects the optical signal from the light source 41. Upon detecting the optical signal, it generates a voltage difference between the positive terminal 431 and the negative terminal 432. The positive terminal 431 of the photodiode array 43 is connected to the ground terminal GT. The photodiode array 43 contains multiple silicon photodiodes. The multiple silicon photodiodes are connected in series in an array, but are not limited to this configuration. Similarly, the voltage difference between the positive terminal 431 and the negative terminal 432 of the photodiode array 43 is, for example, 10V to 25V. The voltage difference depends on the number of silicon photodiodes connected in series.

[0038] The first depletion-type wide-bandgap semiconductor switch 45 has a first source electrode, a first drain electrode, and a first gate electrode. The first gate electrode is connected to the negative terminal 432 of the photodiode array 43. The first drain electrode is connected to the first output terminal OT1. The second depletion-type wide-bandgap semiconductor switch 47 has a second source electrode, a second drain electrode, and a second gate electrode. The second gate electrode is connected to the negative terminal of the photodiode array 43. The second source electrode is connected to the first source electrode. The second drain electrode is connected to the second output terminal OT2. When the photodiode array 43 detects an optical signal and a voltage difference occurs between the positive terminal 431 and the negative terminal 432, the voltage of the first gate electrode of the first depletion-type wide-bandgap semiconductor switch 45 and the voltage of the second gate electrode of the second depletion-type wide-bandgap semiconductor switch 47 become negative voltages smaller than the threshold voltage (which is a negative voltage). As a result, the first depletion-type wide-bandgap semiconductor switch 45 and the second depletion-type wide-bandgap semiconductor switch 47 are in the off state (i.e., non-conductive). Conversely, if no optical signal is detected by the photodiode array 43, the voltages of the first gate electrode of the first depletion-type wide-bandgap semiconductor switch 45 and the second gate electrode of the second depletion-type wide-bandgap semiconductor switch 47 become 0. As a result, the first depletion-type wide-bandgap semiconductor switch 45 and the second depletion-type wide-bandgap semiconductor switch 47 are in the on state (i.e., conductive).

[0039] The first depletion-type wide-bandgap semiconductor switch 45 and the second depletion-type wide-bandgap semiconductor switch 47 are semiconductor switches with high breakdown field strength and high saturation electron drift rate. For example, the first depletion-type wide-bandgap semiconductor switch 45 and the second depletion-type wide-bandgap semiconductor switch 47 are depletion-type gallium nitride (GaN) high-electron mobility transistors (HEMTs) or silicon carbide (SiC) junction field-effect transistors (JFETs). A depletion-type gallium nitride high-electron mobility transistor, for example, has a breakdown field strength of 3.3 MV / cm and a saturation electron drift rate of 2.5 × 10⁻⁶. 7 The value is cm / s. A silicon carbide junction field-effect transistor, for example, has a breakdown field strength of 3.5 MV / cm and a saturation electron drift rate of 2.0 × 10⁻⁶. 7 It is cm / s.

[0040] As described above, the first depletion-type wide-bandgap semiconductor switch 45 and the second depletion-type wide-bandgap semiconductor switch 47 of the present invention have their gate electrodes connected to the negative terminal 432 of the photodiode array 43. Depending on whether the photodiode array 43 detects an optical signal from the light source 41, a voltage difference is generated between the positive terminal 431 and the negative terminal 432. In this way, the first depletion-type wide-bandgap semiconductor switch 45 and the second depletion-type wide-bandgap semiconductor switch 47 can be quickly switched on and off. As mentioned above, the response time of the enhanced wide-bandgap semiconductor switch is about 5 ns to 50 ns, while the response time of the first depletion-type wide-bandgap semiconductor switch 45 and the second depletion-type wide-bandgap semiconductor switch 47 is short, about 1 ns to 20 ns, making them suitable for applications requiring high-speed switching.

[0041] Similarly, in practice, the light source 41 and the photodiode array 43 are arranged laterally spaced apart on the package substrate. By optical path design (e.g., by placing a reflective coating on top, including silver, aluminum, polyethylene terephthalate (Mylar), or mica), the photodiode array 43 can receive reflected light from the optical signal of the light source 41. Incidentally, in other embodiments, the light source 41 and the photodiode array 43 may be arranged longitudinally spaced apart on different package substrates. The photodiode array 43 receives direct light from the optical signal of the light source 41. As described above, the positional relationship between the light source 41 and the photodiode array 43 can be changed by optical path design, and various positional relationships are covered within the scope of the present invention.

[0042] Figure 5 is a circuit diagram of a wide-bandgap photorelay 5 according to an embodiment of the present invention. Unlike the wide-bandgap photorelay 4, the wide-bandgap photorelay 5 further comprises a control circuit 21 connected between the photodiode array 43 and the depletion-type wide-bandgap semiconductor switch pair. The control circuit 21 can further increase the switching speed. As mentioned above, as shown in Figure 2B, the control circuit 21 includes a transistor, two resistors, and a diode, but the present invention is not limited to this circuit configuration.

[0043] FIG. 6 is a circuit diagram showing a wide bandgap photo relay 6 according to an embodiment of the present invention. Different from the wide bandgap photo relay 4, the wide bandgap photo relay 6 further includes a first diode 61 and a second diode 63. As shown in FIG. 6, the anode and cathode of the first diode 61 are connected to the first source electrode and the first drain electrode of the first depletion-type wide bandgap semiconductor switch 45, respectively. The anode and cathode of the second diode are connected to the second source electrode and the second drain electrode of the second depletion-type wide bandgap semiconductor switch 47, respectively. In this way, the first depletion-type wide bandgap semiconductor switch 45 and the second depletion-type wide bandgap semiconductor switch 47 further have, for example, reverse bias protection and overvoltage protection so that the first depletion-type wide bandgap semiconductor switch 45 and the second depletion-type wide bandgap semiconductor switch 47 operate with correct polarities.

[0044] The above wide bandgap photo relays 1 to 6 can be modularized respectively. This module can be used in consumer electronic devices, automation / control systems, communication systems, electric vehicles, etc., and provides a switching function by connecting to other circuits.

[0045] FIG. 7 is a timing chart showing the states of each component during the operation of a wide bandgap photo relay (for example, the wide bandgap photo relays 1 to 6 in the above embodiment) according to an embodiment of the present invention. V in is the voltage input from the first input terminal IT1 and the second input terminal IT2. The driving voltage of the light source (for example, the light source 11 or the light source 41) is usually from 3V to 5V. I LED is the driving current flowing through the light source and corresponds to V in I LED is usually from 0.5 mA to 10 mA. Φ LED is the radiant flux of the optical signal of the light source and is usually in units of milliwatts (mW).

[0046] I PDA This is the detection current generated when an optical signal is detected by a photodiode array (e.g., photodiode array 13 or photodiode array 43), and is typically 10uA to 100uA. PDA This is the detected voltage between the positive and negative terminals of the photodiode array, obtained by detecting an optical signal, and is typically 20V to 30V. th V is the threshold voltage of a depletion-type wide-bandgap semiconductor switch, and it is a negative voltage. G V is the gate voltage of the depletion-type wide-bandgap semiconductor switch (for example, depletion-type wide-bandgap semiconductor switch 15, first depletion-type wide-bandgap semiconductor switch 45, second depletion-type wide-bandgap semiconductor switch 47). In this invention, the positive terminal of the photodiode array is connected to the ground terminal GT, so V G is -V PDA It becomes equal to, and is usually -5V to -25V, V th Smaller. As shown in Figure 7, I out This is the output current between the first output terminal OT1 and the second output terminal OT2, and is 0 to I dd It switches between these two states. dd This is the input current on the high-voltage load side, and is typically between 1A and 50A.

[0047] As can be seen from Figure 7, when a voltage is input from the first input terminal IT1 and the second input terminal IT2 (i.e., V in When the bias voltage is turned on, the light source is driven (i.e., the light source lights up), and an optical signal is generated. At this time, V G is -V PDA Therefore, the depletion-type wide-bandgap semiconductor switch turns off. Subsequently, if no voltage is input from the first input terminal IT1 and the second input terminal IT2 (i.e., V in If the bias voltage is turned off, the light source will not be driven (i.e., the light source will be turned off). G Since V is 0V, the depletion-type wide-bandgap semiconductor switch turns on. Therefore, V inThe light source can be switched on and off by turning the bias on or off, allowing for quick switching between modes.

[0048] As described above, the wide-bandgap photorelay according to the present invention can improve the off-state voltage and switching speed by using a depletion-type wide-bandgap semiconductor switch. Therefore, compared to conventional photorelays, the wide-bandgap photorelay of the present invention has characteristics such as high voltage resistance, high-speed switching, high reliability, and high durability, and can meet the needs of various applications.

[0049] The above-described embodiments illustrate embodiments of the present invention and describe the characteristic configuration of the present invention. The present invention is not limited to the above embodiments. Modifications or equivalent arrangements that can be easily made by those skilled in the art are also within the scope of the present invention. The scope of protection of the rights of the present invention shall be based on the claims. [Explanation of symbols]

[0050] 1. Widebandgap photorelay 2 Widebandgap Photorelay 3. Widebandgap photorelay 4 Widebandgap Photorelay 5 Widebandgap Photorelay 6. Widebandgap photorelay IT1 First Input Terminal IT2 Second Input Terminal OT1 First Output Terminal OT2 Second Output Terminal GT Ground Terminal 11 Light source 41 Light source 13 Photodiode Array 43 Photodiode Array 15. Depletion-type widebandgap semiconductor switches 45. First Depletion Type Wide Bandgap Semiconductor Switch 47. Second Depletion Type Wide Bandgap Semiconductor Switch 111 1st end 411 1st end 112 2nd end 412 2nd end 131 Positive terminal 431 Positive terminal 132 Negative terminal 432 negative terminal 21 Control circuits 31 diodes 61 First Diode 63. Second Diode

Claims

1. It is a widebandgap photorelay, First input terminal and, Second input terminal and First output terminal and, Second output terminal and, Ground terminal and A light source that generates an optical signal and has a first end connected to the first input terminal and a second end connected to the second input terminal, A photodiode array is installed separately from the light source, has a positive terminal and a negative terminal, and when it detects the optical signal, it generates a voltage difference between the positive terminal and the negative terminal, and the positive terminal is connected to the ground terminal. A depletion-type wide-bandgap semiconductor switch having a gate electrode connected to the negative terminal, a drain electrode connected to the first output terminal, and a source electrode connected to the second output terminal, A wide-bandgap photorelay in which the positive terminal of the photodiode array is not connected to the source electrode, the drain electrode, the first output terminal, and the second output terminal.

2. The wide-bandgap photorelay according to claim 1, characterized in that the light source is a gallium arsenide (GaAs) light-emitting diode (LED).

3. The wide bandgap photorelay according to claim 1, characterized in that the photodiode array includes a plurality of silicon photodiodes connected in series in an array.

4. The wide bandgap photorelay according to claim 1, further comprising a control circuit connected between the photodiode array and the depletion-type wide bandgap semiconductor switch.

5. The wide-bandgap photorelay according to claim 1, characterized in that the depletion-type wide-bandgap semiconductor switch is a depletion-type gallium nitride (GaN) high electron mobility transistor (HEMT) or a silicon carbide (SiC) junction field-effect transistor (JFET).

6. The wide bandgap photorelay according to claim 1, characterized in that the light source and the photodiode array are arranged laterally relative to each other.

7. The wide bandgap photorelay according to claim 1, characterized in that the light source and the photodiode array are arranged vertically relative to each other.

8. Equipped with an additional diode, The wide bandgap photorelay according to claim 1, characterized in that the anode of the diode is connected to the source electrode and the cathode of the diode is connected to the drain electrode.

9. It is a widebandgap photorelay, First input terminal and, Second input terminal and First output terminal and, Second output terminal and, Ground terminal and A light source that generates an optical signal and has a first end connected to the first input terminal and a second end connected to the second input terminal, A photodiode array is installed separately from the light source, has a positive terminal and a negative terminal, and when it detects the optical signal, it generates a voltage difference between the positive terminal and the negative terminal, and the positive terminal is connected to the ground terminal. A pair of depletion-type wide-bandgap semiconductor switches comprising a first depletion-type wide-bandgap semiconductor switch and a second depletion-type wide-bandgap semiconductor switch, The first depletion-type wide-bandgap semiconductor switch has a first gate electrode connected to the negative terminal, a first drain electrode connected to the first output terminal, and a first source electrode. The second depletion-type wide-bandgap semiconductor switch has a second gate electrode connected to the negative terminal, a second source electrode connected to the first source electrode, and a second drain electrode connected to the second output terminal. A wide-bandgap photorelay in which the positive terminal of the photodiode array is not connected to the first source electrode, the first drain electrode, the second source electrode, the second drain electrode, the first output terminal, and the second output terminal.

10. The wide-bandgap photorelay according to claim 9, characterized in that the light source is a gallium arsenide (GaAs) light-emitting diode (LED).

11. The wide bandgap photorelay according to claim 9, characterized in that the photodiode array includes a plurality of silicon photodiodes connected in series in an array.

12. The wide bandgap photorelay according to claim 9, further comprising a control circuit connected between the photodiode array and the depletion-type wide bandgap semiconductor switch pair.

13. The wide-bandgap photorelay according to claim 9, characterized in that the first depletion-type wide-bandgap semiconductor switch and the second depletion-type wide-bandgap semiconductor switch are depletion-type gallium nitride (GaN) high electron mobility transistors (HEMT) or silicon carbide (SiC) junction field-effect transistors (JFETs).

14. The wide bandgap photorelay according to claim 9, characterized in that the light source and the photodiode array are arranged laterally relative to each other.

15. The wide bandgap photorelay according to claim 9, characterized in that the light source and the photodiode array are arranged vertically relative to each other.

16. Further comprising a first diode and a second diode, The wide bandgap photorelay according to claim 9, characterized in that the anode of the first diode is connected to the first source electrode, the cathode of the first diode is connected to the first drain electrode, the anode of the second diode is connected to the second source electrode, and the cathode of the second diode is connected to the second drain electrode.

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