Semiconductor switch controller and digital protection device with same

Abstract

The invention discloses a semiconductor switch controller and a digital protection device with the same. The semiconductor switch controller includes an attenuation circuit and a control circuit. The attenuation circuit connects the first end and the second end of the semiconductor switch. The attenuation circuit attenuates voltages of the first end and the second end of the semiconductor switch to form a first attenuation voltage and a second attenuation voltage respectively and outputs the first attenuation voltage and the second attenuation voltage to the control circuit. The control circuit determines an over-temperature critical value, an over-voltage critical value and an overload critical value according to a plurality of set voltages, and the over-temperature critical value, the over-voltage critical value and the overload critical value are respectively used for controlling the semiconductor switches.

Description

Technical Field

[0001] The present invention relates to semiconductor switches, and in particular to a semiconductor switch controller and a digital protection device having the semiconductor switch controller. Background Art

[0002] Relays are mainly contact relays and non-contact relays. Non-contact (non-contact type) relays, such as solid-state relays, use semiconductor devices as switching components, and no electric sparks are generated during the switching process, resulting in a very long switching life. However, since all switching components have a conduction voltage drop, the switching components will be damaged due to overheating when conducting. Currently, commercially available DC solid-state relays do not have over-temperature, overload, and over-voltage protection mechanisms at the same time, nor do they provide the function of digitally displaying data on a display device. Summary of the Invention

[0003] The present invention provides a semiconductor switch controller for the deficiencies of the prior art. The semiconductor switch controller of the present invention is connected to a semiconductor switch, a driving circuit, a temperature sensing circuit, and a threshold setting circuit. The first end and the second end of the semiconductor switch are respectively connected to a voltage source and a load. The driving circuit is connected to the control end of the semiconductor switch. The temperature sensing circuit is used to measure the semiconductor switch and output a temperature sensing voltage value. The semiconductor switch controller includes an attenuation circuit and a control circuit. The attenuation circuit is connected to the first end of the semiconductor switch to output a first attenuation voltage, and is connected to the second end of the semiconductor switch to output a second attenuation voltage. The control circuit is connected to the attenuation circuit, the driving circuit, the temperature sensing circuit, and the threshold setting circuit. The control circuit drives and controls the semiconductor switch via the driving circuit. The control circuit receives a plurality of setting voltages from the threshold setting circuit and converts them into an over-temperature threshold, an over-voltage threshold, and an overload threshold through the control circuit. After converting the temperature sensing voltage value into a temperature digital signal, the control circuit compares the temperature digital signal with the over-temperature threshold to determine whether an over-temperature event occurs, and the control circuit decides whether to adjust the control of the semiconductor switch accordingly. After converting the first attenuation voltage into a first digital signal, the control circuit compares the first digital signal with the over-voltage threshold to determine whether an over-voltage event occurs, and the control circuit decides whether to adjust the control of the semiconductor switch accordingly. After converting the second attenuation voltage into a second digital signal, the control circuit compares the difference between the first digital signal and the second digital signal with the overload threshold to determine whether an overload event occurs, and the control circuit decides whether to adjust the control of the semiconductor switch accordingly.

[0004] The present invention also provides a digital protection device with a semiconductor switch controller, which includes a semiconductor switch, a temperature sensing circuit, a driving circuit, an attenuation circuit, a threshold setting circuit, a control circuit, and an opto-coupler. The first end of the semiconductor switch is connected to a voltage source, and the second end of the semiconductor switch is connected to a load. The temperature sensing circuit outputs a temperature sensing voltage value according to the measurement of the semiconductor switch. The driving circuit is connected to the control end of the semiconductor switch. The attenuation circuit is connected to the first end and the second end of the semiconductor switch to generate a first attenuation voltage and a second attenuation voltage respectively. The threshold setting circuit outputs a plurality of setting voltages. The control circuit is connected to the temperature sensing circuit, the driving circuit, the attenuation circuit, and the threshold setting circuit. The control circuit drives and controls the semiconductor switch via the driving circuit. The control circuit receives the plurality of setting voltages from the threshold setting circuit and converts them into an over-temperature threshold, an over-voltage threshold, and an overload threshold. The opto-coupler is coupled between the control circuit and an external main control device. After converting the temperature sensing voltage value into a temperature digital signal, the control circuit compares the temperature digital signal with the over-temperature threshold to determine whether an over-temperature event occurs, and the control circuit decides whether to adjust the control of the semiconductor switch accordingly. After converting the first attenuation voltage into a first digital signal, the control circuit compares the first digital signal with the over-voltage threshold to determine whether an over-voltage event occurs, and decides whether to adjust the control of the semiconductor switch accordingly. After converting the second attenuation voltage into a second digital signal, the control circuit compares the difference between the first digital signal and the second digital signal with the overload threshold to determine whether an overload event occurs, and decides whether to adjust the control of the semiconductor switch accordingly.

[0005] As described above, the present invention provides a semiconductor switch controller and a digital protection device with a semiconductor switch controller. The voltage and power of the semiconductor switch can be detected simultaneously and compared with a plurality of thresholds respectively to determine whether over-temperature, over-voltage, and overload events occur. Moreover, the digital protection device with a semiconductor switch controller of the present invention can set a plurality of fixed resistors with specified resistance values, or set a plurality of variable resistors as a user-friendly interface. Engineers can also flexibly set the resistance values of these resistors, and then set the plurality of thresholds for determining whether the above-mentioned over-temperature, over-voltage, and overload events occur. In addition, the data detected in the semiconductor switch controller and the digital protection device with a semiconductor switch controller of the present invention, as well as information such as whether over-temperature, over-voltage, and overload events occur, can be transmitted to an external display device for digital real-time dynamic display.

[0006] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the provided drawings are only for reference and illustration, and are not used to limit the present invention. Description of the Drawings

[0007] Figure 1 This is the circuit diagram of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0008] Figure 2 This is the circuit diagram of the threshold setting circuit of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0009] Figure 3 This is the circuit diagram of the semiconductor switch of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0010] Figure 4 This is a schematic diagram of the information displayed on the digital character display device of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0011] Figure 5 This is the flowchart of the steps of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0012] Figure 6 This is the flowchart of the steps of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0013] Figure 7 This is the flowchart of the steps of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention. Detailed implementation manners

[0014] The following are specific embodiments to illustrate the implementation manners of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. Additionally, the drawings of the present invention are only simple schematic illustrations and are not drawn according to actual sizes, which is stated in advance. The following implementation manners will further detail the related technical content of the present invention, but the disclosed content is not used to limit the protection scope of the present invention. In addition, the term "or" used herein should, depending on the actual situation, possibly include any one or a combination of more of the associated listed items.

[0015] Please refer to Figure 1 This is the circuit diagram of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0016] The digital protection device PDE with a semiconductor switch controller according to an embodiment of the present invention includes a semiconductor switch controller AT, a semiconductor switch Q1, a drive circuit DRV, a threshold setting circuit THS, a digital character display device LCD, a light-emitting diode LED, a voltage source VS, a load LD, and a temperature sensing circuit TEM. The semiconductor switch controller AT includes a control circuit CTR and an attenuation circuit ATE.

[0017] One end of the semiconductor switch Q1 (for example Figure 1 shown as the drain D of the N-MOSFET) is connected to a voltage source VS to output a first analog high voltage H-Vd from this voltage source VS. The second end of the semiconductor switch Q1 (for example Figure 1 the source S) is connected to the load LD and receives a second analog high voltage H-Vs.

[0018] The attenuation circuit ATE is connected to the first end and the second end of the semiconductor switch Q1 and the control circuit CTR. The control circuit CTR is connected to the drive circuit DRV. The drive circuit DRV is connected to the control end of the semiconductor switch Q1 (for example Figure 1 the gate G).

[0019] After the attenuation circuit ATE receives the first analog high voltage H-Vd and performs attenuation processing, it forms a first attenuated voltage L-Vd and then outputs it to the control circuit CTR.

[0020] After the attenuation circuit ATE receives the second analog high voltage H-Vs and performs attenuation processing, it forms a second attenuated voltage L-Vs and then outputs it to the control circuit CTR.

[0021] The temperature sensing circuit TEM is disposed near the semiconductor switch Q1 and is electrically connected to the control circuit CTR. The temperature sensing circuit TEM measures the temperature sensing voltage value of the semiconductor switch Q1 and outputs it to the control circuit CTR.

[0022] The control circuit CTR is connected to the threshold setting circuit THS. The control circuit CTR determines an over-temperature threshold, an over-voltage threshold, and an overload threshold respectively according to a plurality of set voltages Vth1 to Vth3 received from the threshold setting circuit THS.

[0023] When the control circuit CTR controls the drive circuit DRV to drive the semiconductor switch Q1 to operate, the voltage, power, and temperature of the semiconductor switch Q1 will increase, and over-temperature, over-voltage, and overload events may occur, resulting in damage to the semiconductor switch Q1. Therefore, the following operations are performed.

[0024] After converting the received first attenuated voltage L-Vd into a first digital signal, the control circuit CTR compares the first digital signal with an overvoltage threshold value to determine whether an overvoltage event has occurred, and accordingly decides whether to adjust the control of the semiconductor switch Q1. When the first digital signal is higher than an overvoltage threshold value, the control circuit CTR determines that an overvoltage event has occurred, and the control circuit CTR controls the drive circuit DRV to turn off the semiconductor switch Q1. Then, when the voltage at the first terminal (drain D) of the semiconductor switch Q1 decreases and is attenuated to form a first attenuated voltage L-Vd, and the first attenuated voltage L-Vd is converted into a first digital signal that is lower than an overvoltage threshold value, the control circuit CTR controls the drive circuit DRV to turn on the semiconductor switch Q1 again.

[0025] After converting the second attenuated voltage L-Vs into a second digital signal, the control circuit CTR compares the difference between the first digital signal and the second digital signal with an overload voltage threshold value to determine whether an overload event has occurred, and accordingly decides whether to adjust the control of the semiconductor switch Q1.

[0026] After converting a temperature sensing voltage value received from the temperature sensing circuit TEM into a temperature digital signal, the control circuit CTR compares the temperature digital signal with an overtemperature threshold value to determine whether an overtemperature event has occurred, and accordingly decides whether to adjust the control of the semiconductor switch Q1.

[0027] When the temperature digital signal is greater than an overtemperature threshold value, the control circuit CTR controls the drive circuit DRV to turn off the semiconductor switch Q1. After the semiconductor switch Q1 is turned off, the semiconductor switch Q1 will slowly cool down.

[0028] When the temperature of the semiconductor switch Q1 slowly drops and is re-measured by the temperature sensing circuit TEM to output a temperature sensing voltage value, the control circuit CTR converts the temperature sensing voltage value into a new temperature digital signal. When this new temperature digital signal is lower than the difference between an overtemperature threshold value minus a hysteresis temperature, the control circuit CTR controls the drive circuit DRV to turn on the semiconductor switch Q1 again. For example, the temperature difference threshold value is set at 110 °C and the hysteresis temperature is defaulted at 10 °C. When the temperature of the semiconductor switch Q1 rises to 111 °C, the control circuit CTR controls to turn off the semiconductor switch Q1. When the temperature of the semiconductor switch Q1 slowly drops to 99 °C (lower than the difference between the set temperature difference threshold value of 110 °C minus the default hysteresis temperature of 10 °C, which is 100 °C), the control circuit CTR controls to turn on the semiconductor switch Q1 again. This hysteresis temperature value is a default value and is not set externally, and can be changed according to actual requirements.

[0029] That is, the control circuit CTR can control the operation of the semiconductor switch Q1 in a hysteresis control manner to prevent the semiconductor switch Q1 from being turned on and off at the same temperature point, resulting in unstable switching of the semiconductor switch Q1.

[0030] As described above, in the embodiment of the present invention, the over-temperature protection, overload protection, and over-voltage protection mechanisms are executed in the semiconductor switch controller AT and the digital protection device PDE having the semiconductor switch controller AT to prevent the semiconductor switch Q1 from being damaged due to over-temperature, overload, or over-voltage.

[0031] As Figure 1 shown, the attenuation circuit ATE of the digital protection device PDE of the present invention includes a plurality of first resistors Ra11 to Ra14 and a plurality of second resistors Ra21 to Ra24, but the present invention is not limited thereto. In practice, the number and resistance values of the plurality of (first and second) resistors included in the attenuation circuit ATE may depend on the voltages at the first end (drain D) and the second end (source S) of the semiconductor switch Q1.

[0032] The plurality of first resistors Ra11 to Ra14 are arranged in sequence and connected in series with each other. The first end of the first resistor Ra11 is connected to the first end (drain D) of the semiconductor switch Q1. The first end of the first resistor Ra12 is connected to the second end of the first resistor Ra11. The first end of the first resistor Ra13 is connected to the second end of the first resistor Ra12. The first end of the first resistor Ra14 is connected to the second end of the first resistor Ra13. The second end of the first resistor Ra14 is grounded.

[0033] The plurality of second resistors Ra21 to Ra24 are arranged in sequence and connected in series with each other. The first end of the second resistor Ra21 is connected to the second end (source S) of the semiconductor switch Q1. The first end of the second resistor Ra22 is connected to the second end of the second resistor Ra21. The first end of the second resistor Ra23 is connected to the second end of the second resistor Ra22. The first end of the second resistor Ra24 is connected to the second end of the second resistor Ra23. The second end of the second resistor Ra24 is grounded.

[0034] The control circuit CTR is connected to the first end of the first resistor Ra14 and the first end of the second resistor Ra24. The control circuit CTR obtains the voltage at the first end of the first resistor Ra14 as the first attenuation voltage described above, and obtains the voltage at the first end of the second resistor Ra24 as the second attenuation voltage.

[0035] If necessary, the digital protection device PDE having the semiconductor switch controller AT of the present invention may further include a resistor Rr connected between the control circuit CTR and the drive circuit DRV. The first end of the resistor Rr is connected to the control circuit CTR, and the second end of the resistor Rr is connected to the drive circuit DRV.

[0036] It should be noted that, as Figure 1 shown, the threshold value setting circuit THS includes a plurality of resistors Rth1, Rth2, Rth3, all of which are variable resistors.

[0037] The plurality of resistors Rth1, Rth2, Rth3 are connected in parallel with each other. The first ends of the respective resistors Rth1, Rth2, Rth3 can be coupled to a shared voltage VDD, such as 5V. The second ends of the respective resistors Rth1, Rth2, Rth3 can be grounded. The control terminals of the respective resistors Rth1, Rth2, Rth3 are connected to a control circuit CTR. The plurality of resistors Rth1, Rth2, Rth3 generate a plurality of set voltages.

[0038] The control circuit CTR determines the above-mentioned over-temperature threshold value according to the set voltage value of the resistor Rth1 of the threshold value setting circuit THS, determines the above-mentioned overload threshold value according to the set voltage value of the resistor Rth2 of the threshold value setting circuit THS, and determines the above-mentioned over-voltage threshold value according to the set voltage value of the resistor Rth3 of the threshold value setting circuit THS.

[0039] The control circuit CTR detects and obtains the shared voltage VDD (5V), and detects the set voltage values in the adjustable range of 0% (0V) to 100% (5V) of the resistors Rth1 to Rth3 in the threshold value setting circuit THS. The control circuit CTR can then know at which adjustment position in the range of 0% to 100% the set voltage values of the variable resistors Rth1 to Rth3 are. For example, if the control circuit CTR detects that the threshold value set voltage value of the resistor Rth1 is 1V, it can know that the adjustment position of the variable resistor Rth1 is at 20%. When it detects that the threshold value set voltage value of Rth1 is 2.5V, it can know that the adjustment position of the variable resistor Rth1 is at 50%. According to engineering requirements, the adjustment position of the resistor Rth1 in the range of 0% to 100% can define (60°C to 200°C) as the over-temperature threshold value, the adjustment position of the resistor Rth2 in the range of 0% to 100% can define (0V to 20V) as the overload threshold value, and the adjustment position of the resistor Rth3 in the range of 0% to 100% can define (100V to 1200V) as the over-voltage threshold value. That is, the variable resistors are used as voltage dividers for the shared voltage VDD (5V). When the engineering setting is completed, the product can also be as Figure 2 , use two fixed resistors Rt11, Rt12, to replace a variable resistor Rth1.

[0040] That is to say, the user can manually adjust the adjusted voltage values of the multiple resistors Rth1, Rth2, and Rth3 included in the threshold setting circuit THS respectively, so as to adjust an over-temperature threshold for determining whether an over-temperature event occurs, an overload threshold for determining whether an overload event occurs, and an over-voltage threshold for determining whether an over-voltage event occurs respectively.

[0041] The temperature sensing circuit TEM of the digital protection device PDE of the present invention includes a voltage dividing circuit, and the voltage dividing circuit includes a voltage dividing resistor Rb and a temperature sensing resistor Rntc. The resistance value of the temperature sensing resistor Rntc changes with temperature. For example, the temperature sensing resistor Rntc is a negative temperature coefficient thermistor, and its resistance value decreases as the temperature increases and increases as the temperature decreases.

[0042] The first end of the voltage dividing resistor Rb is coupled to a shared voltage VDD, such as but not limited to 5V. The first end of the temperature sensing resistor Rntc is connected to the second end of the voltage dividing resistor Rb. The second end of the temperature sensing resistor Rntc is grounded.

[0043] The voltage at the first end of the temperature sensing resistor Rntc is expressed by the following formula:

[0044]

[0045] Where Vntc represents the voltage at the first end of the temperature sensing resistor Rntc, VDD represents the shared voltage coupled to the first end of the voltage dividing resistor Rb, Rntc represents the resistance value of the temperature sensing resistor, and Rb represents the resistance value of the voltage dividing resistor.

[0046] The resistance value of the temperature sensing resistor Rntc changes with the temperature of the semiconductor switch Q1 in the digital protection device PDE of the present invention, thereby changing the voltage at the first end of the temperature sensing resistor Rntc. The control circuit CTR is connected to the first end of the temperature sensing resistor Rntc to receive the voltage at the first end of the temperature sensing resistor Rntc and determine the temperature of the semiconductor switch Q1 in the digital protection device PDE accordingly.

[0047] The digital protection device PDE of the present invention further includes a light-emitting component LED, such as a light-emitting diode. The light-emitting component LED can be connected to the control circuit CTR. The control circuit CTR can control the light-emitting component LED to enter different light-emitting modes according to different states of the digital protection device PDE to show different light-emitting states, as exemplified below.

[0048] When the external main control device generates a trigger, it will pass through the connector ET, and then generate a control signal PH-TR through the optocoupler PTC of the optocoupling circuit EXT and transmit it to the control circuit CTR to instruct the control circuit CTR to control the light-emitting component LED to enter the zero mode and remain unlit.

[0049] When the external master device does not generate a trigger, the control circuit CTR controls the light-emitting component LED to enter the first mode and continuously emit light.

[0050] When an over-temperature event occurs, the control circuit CTR can control the light-emitting component LED to enter the second mode and blink once every first time length (such as but not limited to 0.1 second).

[0051] When the temperature sensing circuit (including a voltage-dividing resistor Rb and a temperature-sensitive resistor Rntc) of the digital protection device PDE of the present invention has a fault, such as when the temperature-sensitive resistor Rntc is burned out or has too high a resistance value and cannot operate, the control circuit CTR can control the light-emitting component LED to enter the third mode and blink once every second time length (such as but not limited to 0.3 second).

[0052] When an over-voltage event occurs, the control circuit CTR can control the light-emitting component LED to enter the fourth mode and blink once every third time length (such as but not limited to 0.6 second).

[0053] When an overload or over-current event occurs, the control circuit CTR can control the light-emitting component LED to enter the fifth mode and blink once every fourth time length (such as but not limited to 1 second).

[0054] If necessary, the digital protection device PDE of the present invention may further include a resistor Rd connected between the light-emitting component LED and the control circuit CTR. The first end of the resistor Rd is connected to the control circuit CTR. The second end of the resistor Rd is connected to the anode of the light-emitting component LED. The cathode of the light-emitting component LED is grounded.

[0055] Please refer to Figure 2 , which is the circuit diagram of the threshold setting circuit of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0056] The threshold setting circuit THS1 includes a plurality of voltage-dividing circuits, such as but not limited to Figure 2 the first voltage-dividing circuit DV1 for setting the above-mentioned over-temperature threshold, the second voltage-dividing circuit DV2 for setting the above-mentioned overload threshold, and the third voltage-dividing circuit DV3 for setting the above-mentioned over-voltage threshold as shown.

[0057] In the threshold setting circuit THS1, the first voltage-dividing circuit DV1 includes a first resistor Rt11 and a second resistor Rt12, the second voltage-dividing circuit DV2 includes a first resistor Rt21 and a second resistor Rt22, and the third voltage-dividing circuit DV3 includes a first resistor Rt31 and a second resistor Rt32.

[0058] The first end of the first resistor Rt11 is coupled to a shared voltage VDD. The second end of the first resistor Rt11 is connected to the first end of the second resistor Rt12. The second end of the second resistor Rt12 is grounded. The node between the second end of the first resistor Rt11 and the first end of the second resistor Rt12 is connected to the control circuit CTR.

[0059] The first end of the first resistor Rt21 is coupled to a shared voltage VDD. The second end of the first resistor Rt21 is connected to the first end of the second resistor Rt22. The second end of the second resistor Rt22 is grounded. The node between the second end of the first resistor Rt21 and the first end of the second resistor Rt22 is connected to the control circuit CTR.

[0060] The first end of the first resistor Rt31 is coupled to a shared voltage VDD. The second end of the first resistor Rt31 is connected to the first end of the second resistor Rt32. The second end of the second resistor Rt32 is grounded. The node between the second end of the first resistor Rt31 and the first end of the second resistor Rt32 is connected to the control circuit CTR.

[0061] The value of the first end of the second resistor Rt12 included in the first voltage dividing circuit DV1, such as voltage, the value of the first end of the second resistor Rt22 included in the second voltage dividing circuit DV2, such as voltage, and the value of the first end of the second resistor Rt32 included in the third voltage dividing circuit DV3, such as voltage, are respectively used as multiple set reference values, such as the above-mentioned multiple set voltages Vth1 to Vth3.

[0062] The control circuit CTR respectively determines the above-mentioned over-temperature critical value, over-load critical value, and over-voltage critical value according to the value of the first end of the second resistor Rt12, such as voltage, the value of the first end of the second resistor Rt22, such as voltage, and the value of the first end of the second resistor Rt32, such as voltage.

[0063] Please refer to Figure 3 , which is the circuit diagram of the semiconductor switch of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0064] In practice, as Figure 1 shown, the semiconductor switch Q1 can also be replaced by the semiconductor switch Q2 as Figure 3 shown or other transistors, and the present invention is not limited thereto. As Figure 3 shown, the semiconductor switch Q2 is an Insulated Gate Bipolar Transistor (IGBT), which has a gate G, a collector C, and an emitter E, serving as the control end, the first end, and the second end of the semiconductor switch Q2 respectively.

[0065] Please refer to Figure 4, which is a schematic diagram of the information displayed on the digital text display device of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0066] The control circuit CTR can be connected to one or more external devices. For example, Figure 1 As shown, the control circuit CTR can be coupled to the first end of the resistor Rp through the optocoupler PTC. The second end of the resistor Rp is connected to the external main control device through the connector ET, and the control circuit CTR is connected to the digital text display device LCD.

[0067] For example, as Figure 4 shown, on the first line of the digital text display device LCD, from left to right, the model name of the digital protection device (such as "DC4"), a maximum allowable set value of a voltage threshold (such as "1200V"), the ratio of a currently set overvoltage threshold to a maximum allowable set value of a voltage threshold (such as "92%"), the currently set overvoltage threshold (such as "1109V"), and the level of a touch control signal PH-TR output from the external main control device to the control circuit CTR through the connector ET, the resistor Rp, and the optocoupler PTC (such as "H" representing a high level or "L" representing a low level) can be displayed in sequence.

[0068] For example, as Figure 4 shown, on the second line of the digital text display device LCD, from left to right, the first digital signal of the first attenuation voltage conversion (such as "1000V"), the second digital signal of the second attenuation voltage conversion (such as "996V"), and the difference between this first digital signal and the second signal (such as "+4V") can be displayed in sequence.

[0069] For example, as Figure 4 shown, on the third line of the digital text display device LCD, from left to right, the ratio of a currently set overload threshold to a maximum allowable set value of an overload threshold (such as "100%"), the currently set overload threshold (such as an overvoltage threshold "20V"), the ratio of a currently set overtemperature threshold to a maximum allowable set value of a temperature threshold (such as "30%"), and the currently set overtemperature threshold (such as "110°C") can be displayed in sequence.

[0070] For example, as Figure 4 shown, on the fourth line of the digital text display device LCD, from left to right, as Figure 1The control circuit CTR of the digital protection device PDE shown calculates the temperature digital signal of the digital protection device based on the temperature sensing voltage value at the first end of the temperature sensing resistor Rntc, and displays the temperature (e.g., "97°C"), information indicating whether the temperature sensing resistor Rntc has a fault ("0" indicates that the temperature sensing resistor Rntc is currently in a normal state, "1" indicates that the temperature sensing resistor Rntc has a fault), the current resistance value of the temperature sensing resistor Rntc (e.g., "7643" Ω), as well as Figure 2 the current light emitting state mode of the light emitting component LED of the digital protection device PDE2 shown (e.g., "M1") and the firmware program version used by the digital protection device of the present invention (e.g., "B1").

[0071] Please refer to Figures 5 to 7 , which is a step flowchart of the digital protection device with a semiconductor switch controller according to an embodiment of the present invention.

[0072] In the following, it is described that the digital protection device of the present invention can execute steps S100 to S107, S201 to S212, and S301 to S302 as Figures 5 to 7 shown.

[0073] First, in step S100, the control circuit CTR performs an initialization operation.

[0074] In step S101, the control circuit CTR reads a trigger control signal PH-TR output by the optocoupler PTC, and reads the first attenuation voltage L-Vd, the second attenuation voltage L-Vs, the temperature sensing voltage value Vtnc, and a plurality of set voltages Vth1 to Vth3.

[0075] In step S102, the control circuit CTR converts Vtnc into a temperature digital signal, converts the first attenuation voltage L-Vd into a first digital signal, converts the second attenuation voltage L-Vs into a second digital signal, and calculates the difference between the first digital signal and the second digital signal.

[0076] In step S103, the control circuit CTR converts the plurality of set voltages Vth1 to Vth3 into an over-temperature critical value, an overload critical value, and an over-voltage critical value.

[0077] In step S104, the control circuit CTR determines whether a current temperature digital signal is higher than an over-temperature critical value. If the current temperature digital signal is higher than an over-temperature critical value, step S105 is executed. Conversely, if the current temperature digital signal is not higher than an over-temperature critical value, it enters stage A and executes steps S201 as Figure 6 shown.

[0078] In step S105, the control circuit CTR determines that an over-temperature event has occurred and switches to the second mode described above.

[0079] In step S106, hysteresis control is performed. That is, the control circuit CTR determines whether a current temperature digital signal is higher than the difference between an over-temperature critical value and a hysteresis temperature. If the current temperature digital signal is higher than the difference between an over-temperature critical value and a temperature difference, step S107 is executed. Conversely, if the current temperature digital signal is not higher than the difference between an over-temperature critical value and a hysteresis temperature, then stage A is entered, and step S201 as shown in Figure 6 is executed.

[0080] In step S107, the control circuit CTR determines that an over-temperature event has occurred, switches to the second mode described above, and then enters stage B.

[0081] After stage A, step S201 is entered. The control circuit CTR determines whether the temperature sensing resistor Rntc (such as a thermistor) is faulty.

[0082] In step S202, the control circuit CTR determines that the temperature sensing resistor Rntc (such as a thermistor) is faulty and switches to the third mode described above. The cause of the fault is, for example, that the temperature sensing resistor Rntc is burned out and open-circuited.

[0083] In step S203, the control circuit CTR determines whether the first digital signal described above is higher than an over-voltage critical value. If the first digital signal is higher than an over-voltage critical value, step S204 is executed. Conversely, if the first digital signal is not higher than an over-voltage critical value, step S205 is executed.

[0084] In step S204, the control circuit CTR determines that an over-voltage event has occurred and switches to the fifth mode described above.

[0085] In step S205, the control circuit CTR determines whether the difference between the first digital signal and the second digital signal described above is higher than an overload critical value. If the difference between the first digital signal and the second digital signal is higher than an overload critical value, step S206 is executed. Conversely, if the difference between the first digital signal and the second digital signal is not higher than an overload critical value, step S208 is executed.

[0086] In step S206, the control circuit CTR determines that an overload event has occurred and switches to the fourth mode.

[0087] In step S208, the control circuit CTR determines whether a high-level trigger control signal PH-TR is received. If the control circuit CTR receives a high-level trigger control signal PH-TR, steps S209 and S210 are sequentially executed. Conversely, if the control circuit CTR does not receive a high-level trigger control signal PH-TR, steps S211, S212, and S301 to S302 are sequentially executed.

[0088] In step S209, the control circuit CTR determines that all the currently detected states of the digital protection device are normal and switches to the above-mentioned zero mode.

[0089] In step S210, the control circuit CTR outputs a control signal Vcont to the drive circuit DRV to control the drive circuit DRV to turn off the semiconductor switch Q1. The above step B is as follows Figure 5 In step S107, a temperature event occurs or Figure 6 In step S202, a thermistor failure occurs, in step S204, an overvoltage event occurs, in step S206, an overload event occurs, and in step S209, when a touch control signal PH-TR is received, it will first enter Figure 6 After step D, then execute Figure 7 Step S210 to control the drive circuit DRV to turn off the semiconductor switch Q1.

[0090] In step S211, the control circuit CTR switches to the above-mentioned first mode.

[0091] In step S212, the control circuit CTR outputs a control signal Vcont to the drive circuit DRV to control the drive circuit DRV to turn on the semiconductor switch Q1.

[0092] In step S301, the control circuit CTR transmits all the above data, modes, and status information to be displayed on the digital character display device LCD.

[0093] In step S302, the control circuit CTR controls the light-emitting component LED to enter the mode corresponding to the current state of the digital protection device, such as one of the above-mentioned zero mode and the first mode to the fifth mode, to be lit, not lit, or blink at different time intervals. After step S302, then enter step E, and then return to Figure 5 Step S101, and then repeat the loop operation of the above steps.

[0094] In summary, the present invention provides a semiconductor switch controller and a digital protection device having the semiconductor switch controller. The voltage and power of the semiconductor switch can be detected simultaneously and compared with multiple critical values respectively to determine whether over-temperature, over-voltage, and overload events occur. Moreover, the digital protection device having the semiconductor switch controller of the present invention can set multiple variable resistors as a user-friendly interface, and engineers can also flexibly set the resistance values of these resistors for setting voltage values, thereby setting multiple critical values for determining whether the above-mentioned over-temperature, over-voltage, and overload events occur. In addition, the data detected in the semiconductor switch controller and the digital protection device having the semiconductor switch controller of the present invention, as well as information such as whether over-temperature, over-voltage, and overload events occur, can be transmitted to an external display device for digital real-time dynamic display.

[0095] The above-disclosed content is only the preferred feasible embodiment of the present invention, and does not limit the claims of the present invention. Therefore, all equivalent technical changes made by using the content of the specification and drawings of the present invention are included in the claims of the present invention.

Claims

1. A semiconductor switch controller is connected to a semiconductor switch, a drive circuit, a temperature sensing circuit, and a threshold setting circuit. The first end and the second end of the semiconductor switch are respectively connected to a voltage source and a load. The drive circuit is connected to the control end of the semiconductor switch. The temperature sensing circuit is used to measure the semiconductor switch and output a temperature sensing voltage value, and is characterized in that, The described semiconductor switch controller includes: An attenuation circuit, connected to the first end of the semiconductor switch to output a first attenuation voltage, and connected to the second end of the semiconductor switch to output a second attenuation voltage; And A control circuit, connected to the attenuation circuit, the drive circuit, the temperature sensing circuit, and the threshold setting circuit. The control circuit drives and controls the semiconductor switch via the drive circuit. The control circuit receives multiple setting voltages from the threshold setting circuit and converts them into an over-temperature threshold, an over-voltage threshold, and an overload threshold; Wherein the control circuit converts the temperature sensing voltage value into a temperature digital signal and then compares the temperature digital signal with the over-temperature threshold to determine whether an over-temperature event occurs. Based on this, the control circuit decides whether to adjust the control of the semiconductor switch; Wherein the control circuit converts the first attenuation voltage into a first digital signal and then compares the first digital signal with the over-voltage threshold to determine whether an over-voltage event occurs. Based on this, the control circuit decides whether to adjust the control of the semiconductor switch; Wherein the control circuit converts the second attenuation voltage into a second digital signal, and then compares the difference between the first digital signal and the second digital signal with the overload threshold to determine whether an overload event occurs. Based on this, the control circuit decides whether to adjust the control of the semiconductor switch.

2. The semiconductor switch controller according to claim 1, wherein The attenuation circuit includes: A plurality of first resistors, arranged in sequence and connected in series with each other. The first ends of the plurality of first resistors are connected to the first end of the semiconductor switch, and the other ends of the plurality of first resistors are grounded; And A plurality of second resistors, arranged in sequence and connected in series with each other. The first ends of the plurality of second resistors are connected to the second end of the semiconductor switch, and the other ends of the plurality of second resistors are grounded; Wherein the control circuit is connected to the plurality of first resistors and receives the first attenuation voltage, and is connected to the plurality of second resistors and receives the second attenuation voltage.

3. A digital protection device with a semiconductor switch controller, characterized in that, The described digital protection device with a semiconductor switch controller includes: A semiconductor switch, the first end of which is connected to a voltage source, and the second end of which is connected to a load; A temperature sensing circuit, which outputs a temperature sensing voltage value according to the measurement of the semiconductor switch; A drive circuit, connected to the control end of the semiconductor switch; An attenuation circuit, connected to the first end and the second end of the semiconductor switch to respectively generate a first attenuation voltage and a second attenuation voltage; A threshold setting circuit, which outputs multiple setting voltages; A control circuit, connected to the temperature sensing circuit, the drive circuit, the attenuation circuit, and the threshold setting circuit. The control circuit drives and controls the semiconductor switch via the drive circuit. The control circuit receives the multiple setting voltages from the threshold setting circuit and converts them into an over-temperature threshold, an over-voltage threshold, and an overload threshold; And An opto-coupler is coupled between the control circuit and an external main control device; Wherein, after the control circuit converts the temperature sensing voltage value into a temperature digital signal, the control circuit compares the temperature digital signal with the over-temperature threshold value to determine whether an over-temperature event occurs, and the control circuit accordingly decides whether to adjust the control of the semiconductor switch; Wherein, after the control circuit converts the first attenuated voltage into a first digital signal, the control circuit compares the first digital signal with the over-voltage threshold value to determine whether an over-voltage event occurs, and accordingly decides whether to adjust the control of the semiconductor switch; Wherein, after the control circuit converts the second attenuated voltage into a second digital signal, the control circuit compares the difference between the first digital signal and the second digital signal with the overload threshold value to determine whether an overload event occurs, and accordingly decides whether to adjust the control of the semiconductor switch.

4. The digital protection device with a semiconductor switch controller according to claim 3, characterized in that, The temperature sensing circuit includes: A voltage dividing resistor, the first end of the voltage dividing resistor is coupled to a shared voltage; and A temperature sensing resistor, the first end of the temperature sensing resistor is connected to the second end of the voltage dividing resistor and the control circuit, and the second end of the temperature sensing resistor is grounded; Wherein the control circuit receives the temperature sensing voltage value generated at the first end of the temperature sensing resistor.

5. The digital protection device with a semiconductor switch controller according to claim 3, characterized in that, The digital protection device with a semiconductor switch controller further includes a digital text display device, the digital text display device is connected to the control circuit, and displays the over-temperature threshold value, the over-voltage threshold value, the overload threshold value, the first digital signal, the second digital signal, and the temperature sensing voltage value.

6. The digital protection device with a semiconductor switch controller according to claim 3, characterized in that, The threshold value setting circuit includes a plurality of resistors, the plurality of resistors are connected in parallel with each other, and the control ends of each of the resistors generate the plurality of set voltages and output them to the control circuit, wherein each of the plurality of resistors is a variable resistor.

7. The digital protection device with a semiconductor switch controller according to claim 3, characterized in that, The threshold value setting circuit includes a plurality of voltage dividing circuits, each of the voltage dividing circuits includes a first resistor and a second resistor, the first end of the first resistor is coupled to a shared voltage, the second end of the first resistor is connected to the first end of the second resistor, the second end of the second resistor is grounded, and a node between the second end of the first resistor and the first end of the second resistor outputs the plurality of set voltages to the control circuit.

8. The digital protection device with a semiconductor switch controller according to claim 3, characterized in that, The digital protection device with a semiconductor switch controller further includes: A light emitting component, connected to the control circuit, the control circuit controls the light emitting component to exhibit different light emitting states according to different states; wherein, when the control circuit is not running, the light emitting component remains unlit; Wherein, when the control circuit is running, the light emitting component emits light continuously; Wherein, when an over-temperature event occurs, the light emitting component flashes once every first time length; Wherein, when the temperature sensing circuit has a fault, the light emitting component flashes once every second time length; Wherein, when an over-voltage event occurs, the light emitting component flashes once every third time length; Wherein, when an overload event occurs, the light-emitting component flashes once every fourth time length.

9. The digital protection device with a semiconductor switch controller according to claim 3, characterized in that, The first end of the semiconductor switch is the drain, the second end of the semiconductor switch is the source, and the control end of the semiconductor switch is the gate.

10. The digital protection device with a semiconductor switch controller according to claim 3, characterized in that, The first end of the semiconductor switch is the collector, the second end of the semiconductor switch is the emitter, and the control end of the semiconductor switch is the gate.

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