Electronic load equipment

Abstract

The present disclosure relates to an electronic load device. One embodiment of the present disclosure includes an electronic load device, which includes a measuring resistor, a reference circuit, a transistor and a feedback circuit. The measuring resistor includes a first contact, a second contact, a third contact and a fourth contact. The first contact and the second contact are located at the first end of the measuring resistor, and the third contact and the fourth contact are located at the second end of the measuring resistor. A reference power supply or a reference voltage is electrically connected to the reference circuit. The reference circuit is electrically connected to the first contact of the measuring resistor. The transistor includes a drain, a gate and a source. The reference circuit is electrically connected to the gate of the transistor. One of the source and the drain of the transistor is electrically connected to the second contact of the measuring resistor. The other of the drain and the source of the transistor is electrically connected to the output end of the object to be measured. The feedback circuit is electrically connected to the fourth contact of the measuring resistor. The feedback circuit is electrically connected to the reference circuit.

Description

Technical Field

[0001] The present invention relates to an electronic load device, and more particularly, to an electronic load device including a resistor having four contacts. Background Art

[0002] The resistance of materials used in circuits changes with temperature. The relationship between temperature and resistance can be expressed as the Temperature Coefficient of Resistance (TCR). If the resistance of a material increases with temperature, its TCR is positive; if the resistance of a material decreases with temperature, its TCR is negative. In electronic devices, not only the resistance of the resistor may change with temperature, but also the resistance of the solder. When the resistance of the resistor is close to that of the solder, changes in the resistance of the solder may cause errors in the electronic device.

[0003] The industry generally uses electronic load devices to test power supply devices before they leave the factory. Electronic load devices can simulate the energy consumption behavior of electronic devices to confirm whether the power supply device can supply power to the electronic devices normally. Therefore, electronic load devices are indispensable testing equipment for the development and manufacture of power supply devices. Electronic load devices can consume electrical energy by dissipating power through internal load components, and further simulate energy consumption behaviors in different operating modes by controlling internal load components, such as energy consumption behaviors under full-speed operation or energy consumption behaviors in standby mode. Alternatively, the electronic load device can be used to perform environmental tests together with the power supply device to be tested to confirm the operating conditions of the power supply device to be tested under different environments, such as whether the supply voltage or current is within the rated range, whether it is stable, etc. However, when performing environmental temperature testing, the resistance value of the load component used by the electronic load device changes with temperature. This changed resistance value may cause errors in the measured voltage value or current value, and thus the output voltage or current of the power supply device to be tested cannot be accurately determined. Summary of the invention

[0004] The present disclosure provides a novel electronic load device which can effectively reduce the error caused by the resistance value of the solder.

[0005] Some embodiments of the present disclosure provide an electronic load device. The electronic load device includes a measuring resistor, a reference circuit, a transistor and a feedback circuit. The measuring resistor includes a first contact, a second contact, a third contact and a fourth contact. The first contact and the second contact are located at the first end of the measuring resistor, and the third contact and the fourth contact are located at the second end of the measuring resistor. The reference power supply is electrically connected to the reference circuit. The reference circuit is electrically connected to the first contact of the measuring resistor. The transistor includes a drain, a gate and a source. The reference circuit is electrically connected to the gate of the transistor. One of the source and the drain of the transistor is electrically connected to the second contact of the measuring resistor. The other of the drain and the source of the transistor is electrically connected to the output end of the object to be measured. The feedback circuit is electrically connected to the fourth contact of the measuring resistor. The feedback circuit is electrically connected to the reference circuit.

[0006] Other embodiments of the present disclosure provide an electronic load device, wherein a load current value passing through a second contact of the measuring resistor is determined based on a voltage value across the measuring resistor and a resistance value of the measuring resistor.

[0007] More embodiments of the present disclosure provide an electronic load device, wherein a first current value passing through a first contact of a measuring resistor is smaller than a load current value passing through a second contact of the measuring resistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The present invention will become more understandable according to the detailed description made below with reference to the accompanying drawings. It should be noted that various features may not be drawn to scale. In fact, the size of various features may be arbitrarily increased or decreased for the purpose of clear description.

[0009] Figure 1 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0010] Figure 2 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0011] Figure 3 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0012] Figure 4 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0013] Figure 5 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0014] Figure 6 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0015] Fig. 7A and Figure 7BFIG. 4 is a schematic diagram of a circuit for measuring resistance according to an embodiment of the present disclosure.

[0016] Figure 8 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0017] Fig. 9 FIG. 4 is a circuit diagram of an electronic load device according to an embodiment of the present disclosure.

[0018] Fig. 10A and Fig. 10B FIG. 4 is a schematic diagram of a circuit for measuring resistance according to an embodiment of the present disclosure.

[0019] Explanation of symbols

[0020] 100: Electronic load equipment

[0021] 102: Reference Circuit

[0022] 104: Feedback Circuit

[0023] 106: Object to be tested

[0024] 108: Measuring resistance

[0025] 110: Transistor

[0026] 112: Grounding point

[0027] 114: Digital control circuit

[0028] 200: Electronic load equipment

[0029] 208: Measuring resistance

[0030] 300: Electronic load equipment

[0031] 400: Electronic load equipment

[0032] 500: Electronic load equipment

[0033] 600: Electronic load equipment

[0034] 800: Electronic load equipment

[0035] 900: Electronic load equipment

[0036] A: Node

[0037] ADC1: Analog-to-digital converter

[0038] AMP1: Operational amplifier

[0039] AMP2: Operational amplifier

[0040] AMP3: Operational Amplifier

[0041] AMP4: Operational Amplifier

[0042] B: Node

[0043] C: Node

[0044] C1: Contact

[0045] C2:Contact

[0046] C3:Contact

[0047] C4: Contact

[0048] C5: Contact

[0049] C6: Contact

[0050] D: Node

[0051] I1: Current

[0052] I LOAD :Load current

[0053] I REF : Reference current

[0054] V REF : Reference power supply

[0055] VM: Voltage difference

[0056] VM1: Voltage difference

[0057] R1: Resistor

[0058] R2: Resistor

[0059] R3: Resistor

[0060] R4: Resistor

[0061] R5: Resistor

[0062] R6: Resistor

[0063] RM: resistance value / resistance

[0064] RM1: resistance value / resistance

[0065] RS1: Resistor

[0066] RS2: resistor

[0067] RS3: Resistor

[0068] RS4: Resistor

[0069] RS5: Resistor

[0070] RS6: Resistor DETAILED DESCRIPTION

[0071] The following disclosure provides many different embodiments or examples for implementing the different features of the provided target. Specific examples and configurations of components are described below. Of course, these descriptions are examples only and are not intended to be restrictive. In the present invention, in the following description, the description of the first component being electrically connected or electrically coupled to the second component may include an embodiment formed by a direct electrical connection or electrical coupling between the first component and the second component, and may further include an embodiment in which one or more additional component features are formed between the first component and the second component so that the first component and the second component are not directly electrically connected or electrically coupled. In addition, in the present invention, reference numerals and / or letters may be repeated in the examples. This repetition is for simplification and clarity purposes, and does not indicate the relationship between the various embodiments and / or configurations described.

[0072] The following describes the embodiments of the present invention in detail. However, it should be understood that many applicable concepts provided by the present invention can be implemented in a plurality of specific environments. The specific embodiments described are only illustrative and do not limit the scope of the present invention.

[0073] Figure 1 FIG. 1 is a circuit diagram of an electronic load device 100 according to an embodiment of the present disclosure. In some embodiments, the electronic load device 100 may include a reference circuit 102, a feedback circuit 104, a transistor 110, a reference power source I REF , measuring resistor 108 and grounding point 112 . Figure 1 The direction of the arrow shown in the figure can be used to indicate the current I1 or the load current I LOAD Direction.

[0074] The electronic load device 100 can be electrically connected to the DUT 106. In some embodiments, the current of the DUT 106 can be output from the output terminal of the DUT 106, pass through the electronic load device 100, and then be input into the DUT 106 at the input terminal of the DUT 106. The current output from the output terminal of the DUT 106 may pass through one or more of the reference circuit 102, the feedback circuit 104, the transistor 110, and the measuring resistor 108.

[0075] The measuring resistor 108 may have a resistance value RM. The measuring resistor 108 may have a contact C1, a contact C2, a contact C3, and a contact C4. The contact C1 and the contact C2 of the measuring resistor 108 may be located at one end of the measuring resistor 108; the contact C3 and the contact C4 of the measuring resistor 108 may be located at the other end of the measuring resistor 108. The contact C1 of the measuring resistor 108 may be electrically connected to the reference circuit 102. The contact C2 of the measuring resistor 108 may be electrically connected to the transistor 110. For example, the contact C2 of the measuring resistor 108 may be electrically connected to the drain or source of the transistor 110. The contact C3 of the measuring resistor 108 may be electrically connected to the feedback circuit 104. The contact C4 of the measuring resistor 108 may be electrically connected to the feedback circuit 104.

[0076] The contacts C1, C2, C3 and C4 of the measuring resistor 108 can be electrically connected to different components via soldering materials. Figure 1 In the embodiment of the present invention, the contact C1 of the measuring resistor 108 can be electrically connected to the reference circuit 102 via the first solder joint; the contact C2 of the measuring resistor 108 can be electrically connected to the transistor 110 via the second solder joint; the contact C3 of the measuring resistor 108 can be electrically connected to the feedback circuit 104 via the third solder joint; and the contact C4 of the measuring resistor 108 can be electrically connected to the feedback circuit 104 via the fourth solder joint.

[0077] In some embodiments, the measuring resistor 108 may be a coil made of a single metal or alloy. Contact C1 and contact C2 may be formed by cutting one end of the coil. Contact C3 and contact C4 may be formed by cutting the other end of the coil. Contact C1 and contact C2 of the measuring resistor 108 may be made of the same material and do not include other welding materials. Therefore, contact C1 and contact C2 of the measuring resistor 108 may be homogeneous. Contact C3 and contact C4 of the measuring resistor 108 may be made of the same material and do not include other welding materials. Therefore, contact C3 and contact C4 of the measuring resistor 108 may be homogeneous.

[0078] The current I1 can flow from the contact C1 into the measuring resistor 108. LOAD The current I1 can flow into the measuring resistor 108 from the contact point C2. The current I1 can flow out of the measuring resistor 108 from the contact point C4. LOAD The current I1 can flow out of the measuring resistor 108 from the contact C3. The current I1 can be smaller than the load current I LOAD In some embodiments, the current I1 may be much smaller than the load current I LOAD .

[0079] The reference circuit 102 may be electrically connected to the transistor 110. For example, the reference circuit 102 may be electrically connected to the gate of the transistor 110. The reference circuit 102 may be electrically connected to the feedback circuit 104. The reference circuit 102 may control the voltage or current I1 applied to the gate of the transistor 110 based on the feedback circuit 104. The reference circuit 102 may be electrically connected to the contact C1 of the measuring resistor 108. The reference circuit 102 may be electrically connected to a reference power source V REF In some embodiments, the reference power supply V REF The corresponding reference current I can be generated REF For example, the reference power supply V REF After being set to output a voltage value, a reference current I REF . Reference current I REF Maybe a few milliamps.

[0080] In some embodiments, the reference power supply V REF The load current I can be controlled by adjusting the voltage provided LOAD For example, the reference power supply V REF The reference power supply V is set to output a voltage value REF The output voltage can be passed through a secondary amplifier to control the gate voltage of the transistor 110, thereby controlling the load current I LOAD .

[0081] The gate of the transistor 110 can be electrically connected to the reference circuit 102. The drain or source of the transistor 110 can be electrically connected to the contact C2 of the measuring resistor 108. The source or drain of the transistor 110 can be electrically connected to the output terminal of the object under test 106. Figure 1 In some embodiments, the source of the transistor 110 may be electrically connected to the contact C2 of the measuring resistor 108; the drain of the transistor 110 may be electrically connected to the output terminal of the object under test 106. In some embodiments, the drain of the transistor 110 may be electrically connected to the contact C2 of the measuring resistor 108; the source of the transistor 110 may be electrically connected to the output terminal of the object under test 106. The output terminal of the object under test 106 may be the end point where the current is output from the object under test.

[0082] The feedback circuit 104 may be electrically connected to the reference circuit 102. The feedback circuit 104 may be electrically connected to the contact C3 of the measuring resistor 108. The feedback circuit 104 may be electrically connected to the contact C4 of the measuring resistor 108. The feedback circuit 104 may be electrically connected to the ground point 112. The feedback circuit 104 may be electrically connected to the object under test 106. For example, the feedback circuit 104 may be electrically connected to the input terminal of the object under test 106. The input terminal of the object under test 106 may be a terminal point for inputting current into the object under test.

[0083] Figure 1The electronic load device 100 can be electrically connected to the object under test 106 to measure some physical characteristics of the object under test 106, such as electrical characteristics. In some embodiments, the load current I through the measuring resistor 108 can be determined based on the voltage difference VM across the measuring resistor 108 and the resistance value RM of the measuring resistor 108. LOAD According to Ohm's law, the voltage difference VM, the resistance value RM, the current I1 and the load current I LOAD The relationship between is shown in equation (1).

[0084]

[0085] When the current I1 is much smaller than the load current I LOAD When, according to Ohm's law, the voltage difference VM, the resistance value RM, the current I1 and the load current I LOAD The relationship between is shown in equation (2).

[0086]

[0087] Figure 2 2 is a circuit diagram of an electronic load device 200 according to an embodiment of the present disclosure. The electronic load device 200 may be an embodiment of the electronic load device 100. To more concisely explain the present disclosure, Figure 1 and Figure 2 Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 1 and Figure 2 Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0088] Figure 2 The electronic load device 200 shown may include a resistor R1, a resistor R2, a resistor R3, a resistor R4, an operational amplifier AMP1, and an operational amplifier AMP2. Figure 2 In the embodiment, the resistor R1, the resistor R2, the operational amplifier AMP1 and the reference power supply V REF An inverting closed loop amplifier can be formed. The resistor R1 can be electrically connected to the input terminal (e.g., the inverting input terminal) of the operational amplifier AMP1. The resistor R2 can be electrically connected to the input terminal (e.g., the inverting input terminal) and the output terminal of the operational amplifier AMP1. Reference power supply V REF The ground point 112 may be further electrically connected to the resistor R1. The ground point 112 may be further electrically connected to another input terminal (eg, a non-inverting input terminal) of the operational amplifier AMP1.

[0089] according to Figure 2In the embodiment of the present invention, the resistor R3, the resistor R4, and the operational amplifier AMP2 can form an inverting closed-loop amplifier. The resistor R3 can be electrically connected to the input terminal (e.g., the inverting input terminal) of the operational amplifier AMP2. The resistor R4 can be electrically connected to the input terminal (e.g., the inverting input terminal) of the operational amplifier AMP2. The output terminal of the operational amplifier AMP1 can be further electrically connected to the resistor R3. The measuring resistor 108 can be further electrically connected to the resistor R4 (e.g., via the contact C1). The transistor 110 can be further electrically connected to the output terminal of the operational amplifier AMP2. For example, the gate of the transistor 110 can be further electrically connected to the output terminal of the operational amplifier AMP2. The resistor R5 and the resistor R6 can be further electrically connected to the other input terminal (e.g., the non-inverting input terminal) of the operational amplifier AMP2.

[0090] The inverting closed-loop amplifier including the operational amplifier AMP1 and the inverting closed-loop amplifier including the operational amplifier AMP2 are connected in series. In some embodiments, the combination of the two inverting closed-loop amplifiers can function as Figure 1 The reference circuit 102 is shown. Figure 2 , reference power supply V REF The reference power source V REF The reference circuit 102 can be electrically connected to the contact C1 of the measuring resistor 108. REF The reference circuit 102 may be electrically connected to the transistor 110 (eg, the gate).

[0091] In some embodiments, the resistor R4 can be used to feed back the voltage of the contact point C1 to the operational amplifier AMP2. For example, the voltage of the contact point C1 can be fed back to the operational amplifier AMP2 through the resistor R4, and the reference power source V REF The voltage can be input to the operational amplifier AMP2 through the resistors R1, R2 and R3. In this embodiment, the operational amplifier AMP2 can function as an addition module or a subtraction module.

[0092] In other embodiments, if the reference power source V REF If the reference power supply V REF The voltage of the contact C1 is unchanged, and when the voltage of the contact C1 increases, the voltage of the contact C1 can be input to the operational amplifier AMP2 through the resistor R4. The operational amplifier AMP2 can act as a subtraction module to reduce the output of the operational amplifier AMP2. Thereby, the gate voltage of the transistor 110 can be reduced, the corresponding current can be reduced, and the voltage of the contact C1 can be reduced to achieve balance.

[0093] In other embodiments, if the reference power source VREF If the reference power supply V REF The voltage of the contact C1 is unchanged, and when the voltage of the contact C1 decreases, the voltage of the contact C1 can be input to the operational amplifier AMP2 through the resistor R4. The operational amplifier AMP2 can act as a subtraction module to increase the output of the operational amplifier AMP2. Thereby, the gate voltage of the transistor 110 can be increased, the corresponding current can be increased, and the voltage of the contact C1 can be increased to achieve balance.

[0094] Figure 2 The electronic load device 200 shown may include a resistor R5 and a resistor R6. Figure 2 In some embodiments, the resistor R5 and the resistor R6 are electrically connected to the input terminal (e.g., the non-inverting input terminal) of the operational amplifier AMP2. The resistor R5 can be electrically connected to the ground point 112. The resistor R6 can be electrically connected to the measuring resistor 108 (e.g., via the contact C3 and the contact C4). The resistor R6 can be electrically connected to one end (e.g., the current input terminal) of the object to be measured 106. The resistor R6 can be electrically connected to the ground point 112. In some embodiments, the combination of the resistor R5 and the resistor R6 can function as Figure 1 The feedback circuit 104 is shown.

[0095] Figure 3 FIG. 1 is a circuit diagram of an electronic load device 300 according to an embodiment of the present disclosure. To more concisely explain the present disclosure, Figure 1 and Figure 3 Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 1 and Figure 3 Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0096] refer to Figure 3 , the reference circuit 102 can be connected to the reference power supply V REF The reference circuit 102 may be electrically connected to the transistor 110 (eg, the gate of the transistor 110 ). The reference circuit 102 may be electrically connected to the feedback circuit 104 . Figure 1 The reference circuit 102 shown may be directly electrically connected to the measuring resistor 108 (eg, via the contact C1); Figure 3 The reference circuit 102 shown may be electrically connected to a measuring resistor 108 via a feedback circuit 104 (eg, via a contact C1 ).

[0097] refer to Figure 3 The feedback circuit 104 may be electrically connected to the reference circuit 102. The feedback circuit 104 may be electrically connected to the measuring resistor 108 (eg, via the contact C1 and the contact C4). Figure 1 The feedback circuit 104 shown can be electrically connected to the measuring resistor 108 via the contact C3 and the contact C4; Figure 3 The feedback circuit 104 shown may be electrically connected to the measuring resistor 108 via the contact C1 and the contact C4.

[0098] refer to Figure 3 , the measuring resistor 108 may have a resistance value RM. The measuring resistor 108 may have a contact C1, a contact C2, a contact C3, and a contact C4. The contacts C1 and C2 of the measuring resistor 108 may be located at one end of the measuring resistor 108; the contacts C3 and C4 of the measuring resistor 108 may be located at the other end of the measuring resistor 108. The contact C1 of the measuring resistor 108 may be electrically connected to the feedback circuit 104. The contact C2 of the measuring resistor 108 may be electrically connected to the transistor 110. For example, the contact C2 of the measuring resistor 108 may be electrically connected to the drain or source of the transistor 110. The contact C3 of the measuring resistor 108 may be electrically connected to the ground point 112. The contact C4 of the measuring resistor 108 may be electrically connected to the feedback circuit 104.

[0099] The contacts C1, C2, C3 and C4 of the measuring resistor 108 can be electrically connected to different components via soldering materials. Figure 3 In the embodiment of the present invention, the contact C1 of the measuring resistor 108 can be electrically connected to the feedback circuit 104 via the first welding point; the contact C2 of the measuring resistor 108 can be electrically connected to the transistor 110 via the second welding point; the contact C3 of the measuring resistor 108 can be electrically connected to the ground point 112 via the third welding point; and the contact C4 of the measuring resistor 108 can be electrically connected to the feedback circuit 104 via the fourth welding point.

[0100] The current I1 can flow from the contact C1 into the measuring resistor 108. LOAD The current I1 can flow into the measuring resistor 108 from the contact point C2. The current I1 can flow out of the measuring resistor 108 from the contact point C3. LOAD The current I1 can flow out of the measuring resistor 108 from the contact C2. The current I1 can be smaller than the load current I LOAD In some embodiments, the current I1 may be much smaller than the load current I LOAD .

[0101] The gate of the transistor 110 can be electrically connected to the reference circuit 102. The drain or source of the transistor 110 can be electrically connected to the contact C2 of the measuring resistor 108. The source or drain of the transistor 110 can be electrically connected to the output terminal of the object under test 106. Figure 1In some embodiments, the source of the transistor 110 may be electrically connected to the contact C2 of the measuring resistor 108; the drain of the transistor 110 may be electrically connected to the output terminal of the object under test 106. In some embodiments, the drain of the transistor 110 may be electrically connected to the contact C2 of the measuring resistor 108; the source of the transistor 110 may be electrically connected to the output terminal of the object under test 106. The output terminal of the object under test 106 may be the end point where the current is output from the object under test.

[0102] Figure 3 The electronic load device 300 can be electrically connected to the object under test 106 to measure certain physical characteristics of the object under test 106, such as electrical characteristics. The output terminal of the object under test 106 can be electrically connected to the drain or source of the transistor 110. The input terminal of the object under test 106 can be electrically connected to the ground point 112 and the measuring resistor 108 (for example, via the contact C3). The input terminal of the object under test 106 can be an end point for current input to the object under test. In some embodiments, the load current I through the measuring resistor 108 can be determined based on the voltage difference VM across the measuring resistor 108 and the resistance value RM of the measuring resistor 108. LOAD .

[0103] Figure 4 FIG. 4 is a circuit diagram of an electronic load device 400 according to an embodiment of the present disclosure. The electronic load device 400 may be an embodiment of the electronic load device 300. To more concisely explain the present disclosure, Figure 3 and Figure 4 Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 3 and Figure 4 Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0104] Figure 4 The electronic load device 400 shown may include an operational amplifier AMP3. A measuring resistor 108 (e.g., via a contact C4) may be electrically connected to an input terminal (e.g., an inverting input terminal) of the operational amplifier AMP3. The measuring resistor 108 (e.g., via a contact C1) may be electrically connected to another input terminal (e.g., a non-inverting input terminal) of the operational amplifier AMP3. An output terminal of the operational amplifier AMP3 may be electrically connected to a reference circuit 102. The reference circuit 102 may be based on an output voltage or current of the operational amplifier AMP3 and a reference power supply V REF (or reference current I REF ) to generate a voltage or current applied to the transistor 110 (e.g., the gate of the transistor 110). The voltage or current applied to the transistor 110 (e.g., the gate of the transistor 110) can also be determined based on the voltage or current of the contact C1 and the contact C4. In some embodiments, the operational amplifier AMP3 can function as Figure 3 The feedback circuit 104 is shown.

[0105] Figure 5 FIG. 5 is a circuit diagram of an electronic load device 500 according to an embodiment of the present disclosure. The electronic load device 500 may be an embodiment of the electronic load device 300. To more concisely explain the present disclosure, Figure 3 and Figure 5 Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 3 and Figure 5 Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0106] Figure 5 The electronic load device 500 shown may include an analog-to-digital converter ADC1 and a digital control circuit 114. The measuring resistor 108 (e.g., via the contact C4) may be electrically connected to an input terminal of the analog-to-digital converter ADC1. The measuring resistor 108 (e.g., via the contact C1) may be electrically connected to another input terminal of the analog-to-digital converter ADC1. The output terminal of the analog-to-digital converter ADC1 may be electrically connected to the digital control circuit 114. The digital control circuit 114 may generate an output voltage or current based on the output voltage or current of the analog-to-digital converter ADC1. The output terminal of the digital control circuit 114 may be electrically connected to the reference circuit 102. The reference circuit 102 may generate an output voltage or current based on the output voltage or current of the digital control circuit 114 and a reference power supply V REF (or reference current I REF ) to generate a voltage or current applied to the transistor 110 (e.g., the gate of the transistor 110). The voltage or current applied to the transistor 110 (e.g., the gate of the transistor 110) can also be determined based on the voltage or current of the contact C1 and the contact C4. In some embodiments, the combination of the analog-to-digital converter ADC1 and the digital control circuit 114 can function as Figure 3 The feedback circuit 104 is shown.

[0107] Figure 6 FIG. 6 is a circuit diagram of an electronic load device 600 according to an embodiment of the present disclosure. The electronic load device 600 may be an embodiment of the electronic load device 300. To more concisely explain the present disclosure, Figure 3 and Figure 6 Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 3 and Figure 6 Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0108] Figure 6 The electronic load device 600 shown may include an analog-to-digital converter ADC1, a digital control circuit 114, and an operational amplifier AMP4. The measuring resistor 108 may be electrically connected to an input terminal of the analog-to-digital converter ADC1 (e.g., via a contact C4). The measuring resistor 108 may be electrically connected to another input terminal of the analog-to-digital converter ADC1 (e.g., via a contact C1). The output terminal of the analog-to-digital converter ADC1 may be electrically connected to the digital control circuit 114. The digital control circuit 114 may generate an output voltage based on the output voltage of the analog-to-digital converter ADC1.

[0109] The output terminal of the digital control circuit 114 can be electrically connected to the reference circuit 102. Figure 6 In the embodiment of the present invention, the output terminal of the digital control circuit 114 can be electrically connected to the reference circuit 102 via the operational amplifier AMP4. The output terminal of the digital control circuit 114 can be electrically connected to the input terminal (eg, the inverting input terminal) of the operational amplifier AMP4. REF The output terminal of the operational amplifier AMP4 can be electrically connected to the reference circuit 102 .

[0110] The reference circuit 102 can generate a voltage or current applied to the transistor 110 (eg, the gate of the transistor 110) based on the output voltage or current of the operational amplifier AMP4. The reference circuit 102 can also generate a voltage or current applied to the transistor 110 (eg, the gate of the transistor 110) based on the output voltage or current of the digital control circuit 114 and the reference power supply V REF The voltage or current applied to the transistor 110 (e.g., the gate of the transistor 110) is generated. The voltage or current applied to the transistor 110 (e.g., the gate of the transistor 110) can be further determined based on the voltage or current of the contact C1 and the contact C4. In some embodiments, the combination of the analog-to-digital converter ADC1, the digital control circuit 114, and the operational amplifier AMP4 can function as Figure 3 The feedback circuit 104 is shown. The voltage or current input to the reference circuit 102 can be more accurately controlled by the operational amplifier AMP4. In some embodiments, the operational amplifier AMP4 can also be a subtraction circuit.

[0111] Fig. 7A and Figure 7B FIG. 1 is a circuit diagram of the measuring resistor 108 according to an embodiment of the present disclosure. Figure 7B Can Fig. 7A To more concisely explain the present disclosure, Figure 1 , Figure 2 , Fig. 7A and Figure 7B Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 1 , Figure 2 , Fig. 7A and Figure 7B Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0112] refer to Fig. 7A and Figure 7B , the contacts C1, C2, C3 and C4 of the measuring resistor 108 can be electrically connected to different components via welding materials. Figure 1 In the embodiment of the present invention, the contact C1 of the measuring resistor 108 can be electrically connected to the reference circuit 102 via the first solder joint; the contact C2 of the measuring resistor 108 can be electrically connected to the transistor 110 via the second solder joint; the contact C3 of the measuring resistor 108 can be electrically connected to the feedback circuit 104 via the third solder joint; and the contact C4 of the measuring resistor 108 can be electrically connected to the feedback circuit 104 via the fourth solder joint. Fig. 7A and Figure 7B The middle resistors RS1, RS2, RS3, and RS4 may represent the equivalent resistances of the first solder joint, the second solder joint, the third solder joint, and the fourth solder joint, respectively. When the amount of solder is high, the TCR of each solder joint may be about 14.139ppm / ℃; when the amount of solder is low, the TCR of each solder joint may be about 10.805ppm / ℃; when the amount of solder is moderate, the TCR of each solder joint may be about 12.377ppm / ℃. The TCR of each solder joint may be between 15ppm / ℃ and 10ppm / ℃, or may be between 14.139ppm / ℃ and 10.805ppm / ℃.

[0113] The current I1 can enter the measuring resistor 108 from the connection point C1. The current I1 can leave the measuring resistor 108 from the connection point C4. LOAD The load current I LOAD The current I1 can be smaller than the load current I LOAD In some embodiments, the current I1 can be much smaller than the load current I LOAD .

[0114] Figure 7B Can Fig. 7A Equivalent circuit diagram. Figure 7B , the measuring resistor 108 can be equivalent to a resistor with a resistance value of RM. According to Ohm's law, Fig. 7A and Figure 7B The voltage difference between node A and node B can be expressed as equation (3).

[0115] V AB =I1(RS1+RS4)+(I1+ILOAD )RM.........(3)

[0116] When the current I1 can be much smaller than the load current I LOAD When , the voltage difference caused by the current I1 at the resistors RS1, RS4 and RM can be ignored. Therefore, equation (3) can be further modified to equation (4).

[0117] V AB =I LOAD ×RM..........(4)

[0118] In some embodiments, the measuring resistor 108 may be a coil made of a single metal or alloy. Contact C1 and contact C2 may be formed by cutting one end of the coil. Contact C3 and contact C4 may be formed by cutting the other end of the coil. Contact C1 and contact C2 of the measuring resistor 108 may be made of the same material and do not include other welding materials. Therefore, contact C1 and contact C2 of the measuring resistor 108 may be homogeneous. Contact C3 and contact C4 of the measuring resistor 108 may be made of the same material and do not include other welding materials. Therefore, contact C3 and contact C4 of the measuring resistor 108 may be homogeneous. Generally speaking, according to information provided by suppliers, the TCR of the measuring resistor 108 is approximately between +5ppm / ℃ and -5ppm / ℃ in the range of +20℃ to +60℃. The TCR of the measuring resistor 108 may be less than the TCR of the solder joint.

[0119] Although the TCR of the measuring resistor 108 can be understood from the supplier's data, when the measuring resistor 108 is installed in the electronic load device 100 (or 200, 300, 400, 500, 600), the TCR of the measuring resistor 108 must be measured again to formulate the specification of the electronic load device 100 (or 200, 300, 400, 500, 600). Figure 2 When measuring the TCR of the measuring resistor 108, the load current I can be measured by a current probe. LOAD When measuring the TCR of the measuring resistor 108, the voltage difference VM between the contact C1 and the contact C4 can be measured by a voltmeter. In some embodiments, by measuring Fig. 7A or Figure 7B The voltage difference between node A and node B can also be measured Figure 2 The voltage difference VM between the middle contact C1 and the contact C4.

[0120] Load current I LOAD The change in the amount can be obtained by (I T -I0) / I0, where I0 indicates the initial current, I TIt is the current after the temperature increases by T℃. Therefore, the load current I LOAD The change in voltage difference VM can be expressed by (V T -V0) / V0, where V0 indicates the initial voltage difference, V T is the voltage difference after the temperature increases by T℃. Therefore, the change in voltage difference VM is a proportional value without units, expressed in ppm. According to Ohm's law V=IR, if the resistance R remains unchanged, the change in voltage V is equal to the change in current I. In summary, the load current I LOAD The change in the resistance value RM of the measuring resistor 108 can be obtained by subtracting the change in the voltage difference VM.

[0121] According to some experimental results disclosed herein, when the temperature increases by 23°C, the load current I LOAD The change in V is -57ppm, and the change in the voltage difference VM is -17ppm. After calculation as shown in equation (5), the TCR of the measuring resistor 108 is about 1.73ppm / ℃.

[0122] |(-57-(-17)) / 23|=1.739............(5)

[0123] According to some experimental results disclosed herein, when the temperature increases by 26°C, the load current I LOAD The change in is -97ppm, and the change in voltage difference VM is -50ppm. After calculation as shown in equation (6), the TCR of the measuring resistor 108 is about 1.8ppm / ℃.

[0124] |(-97-(-50)) / 26||=1.807.........(6)

[0125] According to the experimental results disclosed herein, the TCR measured by the measuring resistor 108 installed on the electronic load device 100 (or 200, 300, 400, 500, 600) is still within the TCR range (+5ppm / °C to -5ppm / °C) provided by the supplier.

[0126] In some embodiments, the operating temperature of the electronic load device 100 (or 200, 300, 400, 500, 600) may rise to 75° C. When the operating temperature of the electronic load device 100 (or 200, 300, 400, 500, 600) rises from 25° C. to 75° C., the change in the resistance value RM of the measuring resistor 108 may be 90 ppm (1.8×50=90), i.e., 0.009%. When formulating the specification of the electronic load device 100 (or 200, 300, 400, 500, 600), the 90 ppm change in the resistance value RM of the measuring resistor 108 should be an acceptable measurement error.

[0127] Figure 8 FIG. 8 is a circuit diagram of an electronic load device 800 according to an embodiment of the present disclosure. In some embodiments, the electronic load device 100 may include a reference circuit 102, a feedback circuit 104, a transistor 110, a reference power source I REF , a measuring resistor 208 and a grounding point 112. The electronic load device 100 can be electrically connected to the object under test 106. Figure 8 The direction of the arrow shown in the figure can be used to indicate the direction of current flow. Figure 8 The electronic load device 800 can be electrically connected to the object under test 106 .

[0128] To more concisely explain this disclosure, Figure 1 and Figure 8 Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 1 and Figure 8 Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0129] The measuring resistor 208 may have a resistance value RM1. The measuring resistor 208 may have a contact C5 and a contact C6. The contact C5 of the measuring resistor 208 may be located at one end of the measuring resistor 208; the contact C6 of the measuring resistor 208 may be located at the other end of the measuring resistor 208. The contact C5 of the measuring resistor 208 may be electrically connected to the reference circuit 102. The contact C5 of the measuring resistor 208 may be electrically connected to the transistor 110. For example, the contact C5 of the measuring resistor 208 may be electrically connected to the drain or source of the transistor 110. The contact C6 of the measuring resistor 208 may be electrically connected to the feedback circuit 104.

[0130] Load current I LOAD The load current I LOAD The current I1 can flow out of the measuring resistor 208 from the contact C6. The current I1 can be less than the load current I LOAD In some embodiments, the current I1 may be much smaller than the load current ILOAD .

[0131] The reference circuit 102 can be electrically connected to the contact C5 of the measuring resistor 208. The drain or source of the transistor 110 can be electrically connected to the contact C5 of the measuring resistor 208. The drain or source of the transistor 110 can be electrically connected to the output terminal of the object under test 106. Figure 8 In some embodiments, the source of the transistor 110 may be electrically connected to the contact C5 of the measuring resistor 208; the drain of the transistor 110 may be electrically connected to the output terminal of the object under test 106. In some embodiments, the drain of the transistor 110 may be electrically connected to the contact C5 of the measuring resistor 208; the source of the transistor 110 may be electrically connected to the output terminal of the object under test 106. The output terminal of the object under test 106 may be an end point for outputting current from the object under test 106.

[0132] Figure 8 The electronic load device 800 can be electrically connected to the DUT 106 to measure some physical characteristics of the DUT 106, such as electrical characteristics. In some embodiments, the load current I through the measuring resistor 208 can be determined based on the voltage difference VM1 across the measuring resistor 208 and the resistance value RM1 of the measuring resistor 208. LOAD According to Ohm's law, the voltage difference VM1, the resistance value RM1 and the load current I LOAD The relationship between is shown in equation (7).

[0133]

[0134] Fig. 9 FIG. 9 is a circuit diagram of an electronic load device 900 according to an embodiment of the present disclosure. The electronic load device 900 may be an embodiment of the electronic load device 800. To more concisely explain the present disclosure, Figure 8 and Fig. 9 Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 8 and Fig. 9 Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0135] Compared to Figure 2 , Fig. 9 The middle measuring resistor 208 may be further electrically connected to the resistor R4 (eg, via the contact C5). Figure 2 , Fig. 9 Medium reference power supply V REF The reference power source V REFThe reference circuit 102 can be electrically connected to the contact C5 of the measuring resistor 208. Figure 2 , Fig. 9 The middle resistor R6 may be electrically connected to the measuring resistor 208 (eg, via the contact C6 ).

[0136] Fig. 10A and Fig. 10B FIG. 2 is a circuit diagram of the measuring resistor 208 according to an embodiment of the present disclosure. Fig. 10B Can Fig. 10A To more concisely explain the present disclosure, Figure 8 , Fig. 9 , Fig. 10A and Fig. 10B Components using the same component symbols in the specification may represent the same or similar components, or may represent components having the same or similar functions. Figure 8 , Fig. 9 , Fig. 10A and Fig. 10B Numerical values ​​using the same component symbol may represent the same or similar numerical values, or may represent numerical values ​​having the same or similar physical meanings.

[0137] refer to Fig. 10A and Fig. 10B , the contacts C5 and C6 of the measuring resistor 208 can be electrically connected to different components via welding materials. Figure 8 In the embodiment of the present invention, the contact point C5 of the measuring resistor 208 can be electrically connected to the reference circuit 102 via the fifth solder joint; and the contact point C6 of the measuring resistor 208 can be electrically connected to the feedback circuit 104 via the sixth solder joint. Fig. 10A and Fig. 10B The middle resistor RS5 and the resistor RS6 may represent the equivalent resistance of the fifth solder joint and the sixth solder joint, respectively. When the amount of solder is high, the TCR of each solder joint may be about 14.139ppm / ℃; when the amount of solder is low, the TCR of each solder joint may be about 10.805ppm / ℃; when the amount of solder is moderate, the TCR of each solder joint may be about 12.377ppm / ℃. The TCR of each solder joint may be between 15ppm / ℃ and 10ppm / ℃, or may be between 14.139ppm / ℃ and 10.805ppm / ℃.

[0138] Load current I LOAD The load current I LOAD The measuring resistor 208 can be disconnected from the junction C6.

[0139] Fig. 10B Can Fig. 10A Equivalent circuit diagram. Fig. 10B , the measuring resistor 208 can be equivalent to a resistor with a resistance value of RM1. According to Ohm's law, Fig. 10A and Fig. 10B The voltage difference between the middle node C and the node D can be expressed as equation (8).

[0140] V CD =I LOAD (RS5+RS6+RM1).........(8)

[0141] When the resistors RS5, RS6 and RM1 are close, the voltage difference caused by the resistors RS5 and RS6 cannot be ignored.

[0142] Generally speaking, according to the information provided by the supplier, the TCR of the measuring resistor 208 is approximately between +5ppm / ℃ and -5ppm / ℃ in the range of +20℃ to +60℃. The TCR of the measuring resistor 208 may be less than the TCR of the solder joint. Although the TCR of the measuring resistor 208 can be understood from the supplier's data, when the measuring resistor 208 is installed in the electronic load device 800 (or 900), the TCR of the measuring resistor 208 must be measured again to formulate the specification of the electronic load device 800 (or 900). Fig. 9 When measuring the TCR of the measuring resistor 208, the load current I can be measured by a current probe. LOAD When measuring the TCR of the measuring resistor 208, the voltage difference VM1 between the contact C5 and the contact C6 can be measured by a voltmeter. In some embodiments, by measuring Fig. 10A and Fig. 10B The voltage difference between node C and node D can also be measured Fig. 9 The voltage difference VM1 between the middle contact C5 and the contact C6.

[0143] According to some experimental results disclosed herein, when the temperature increases by 10°C, the load current I LOAD The change in voltage is -324ppm, and the change in voltage difference VM1 is -130ppm. After calculation as shown in equation (9), the TCR of the measuring resistor 208 is about 19.4ppm / ℃.

[0144] |(-324-(-130)) / 10|=19.4............(9)

[0145] According to the experimental results disclosed herein, the TCR obtained by measuring the measuring resistor 208 installed on the electronic load device 800 (or 900) is not within the TCR range (+5ppm / ℃ to -5ppm / ℃) provided by the supplier. This is because the voltage difference caused by the resistors RS5 and RS6 cannot be ignored, resulting in an error in the TCR obtained by measuring the resistor 208.

[0146] In some embodiments, the operating temperature of the electronic load device 800 (or 900) may rise to 75° C. When the operating temperature of the electronic load device 800 (or 900) rises from 25° C. to 75° C., it can be calculated that the change in the resistance value RM1 of the measuring resistor 208 may be 970 ppm (19.4×50=970), that is, 0.097%. When formulating the specification of the electronic load device 800 (or 900), the 90 ppm change in the resistance value RM of the measuring resistor 208 should be an unacceptable measurement error.

[0147] The device or components may be otherwise oriented (rotated 90 degrees or at other orientations) in addition to the orientation shown in the figures and connection-related descriptors used herein may be interpreted accordingly. It will be understood that when a component is "connected," "coupled" or "coupled" to another component, it can be directly connected or coupled to the other component or intervening components may be present.

[0148] As used in the present invention, the terms "approximately", "substantially", "substantially" and "about" are used to describe and explain minor changes. When used in combination with an event or situation, the term may refer to a situation in which the event or situation occurs precisely, and a situation in which the event or situation occurs approximately. As used herein, for a given value or range, the term "approximately" generally refers to within ±10%, ±5%, ±1% or ±0.5% of the given value or range. The range may be indicated herein as from one endpoint to another or between two endpoints. Unless otherwise specified, all ranges disclosed in the present invention include endpoints. The term "substantially coplanar" may refer to two surfaces within a few microns (μm) positioned along the same plane, such as within 10 μm, within 5 μm, within 1 μm or within 0.5 μm positioned along the same plane. When referring to "substantially" the same numerical value or characteristic, the term may refer to a value within ±10%, ±5%, ±1% or ±0.5% of the average value of the value.

[0149] The above briefly describes several embodiments and detailed features of the present invention. The embodiments described in the present invention can be easily used as the basis for designing or modifying other programs and structures for achieving the same or similar goals and / or obtaining the same or similar advantages introduced in the embodiments of the present invention. Such equivalent constructions do not depart from the spirit and scope of the present invention, and various changes, substitutions and modifications can be made without departing from the spirit and scope of the present invention.

Claims

1. An electronic load device, comprising: A measuring resistor, comprising a first contact, a second contact, a third contact and a fourth contact, wherein the first contact and the second contact correspond to a first end of the measuring resistor, and the third contact and the fourth contact correspond to a second end of the measuring resistor; A reference circuit, a reference power supply electrically connected to the reference circuit, and the reference circuit is electrically connected to the first contact of the measuring resistor; A transistor comprising a drain, a gate and a source, wherein the reference circuit is electrically connected to the gate of the transistor, one of the source and the drain of the transistor is directly electrically connected to the second contact of the measuring resistor, and the other of the drain and the source of the transistor is directly electrically connected to the output terminal of the object to be measured; and a feedback circuit, the feedback circuit being electrically connected to the fourth contact of the measuring resistor, the feedback circuit being electrically connected to the reference circuit, The third contact of the measuring resistor is directly electrically connected to the input terminal of the object to be measured, and the first contact of the measuring resistor is electrically connected to the feedback circuit.

2. The electronic load device according to claim 1, wherein a load current value passing through the second connection point of the measuring resistor is determined based on a voltage difference across the measuring resistor and a resistance value of the measuring resistor.

3. The electronic load device according to claim 2, wherein a first current value passing through the first contact of the measuring resistor is smaller than the load current value.

4. The electronic load device according to claim 1, wherein the first contact of the measuring resistor is electrically connected to the reference circuit via a first solder joint, the second contact of the measuring resistor is electrically connected to the transistor via a second solder joint, the third contact of the measuring resistor is electrically connected to the feedback circuit via a third solder joint, and the fourth contact of the measuring resistor is electrically connected to the feedback circuit via a fourth solder joint. 5 . The electronic load device according to claim 4 , wherein a resistance temperature coefficient of the measuring resistor is smaller than resistance temperature coefficients of the first solder joint, the second solder joint, the third solder joint, and the fourth solder joint.

6. The electronic load device according to claim 1, wherein the reference circuit comprises a first inverting closed-loop amplifier and a second inverting closed-loop amplifier, the first inverting closed-loop amplifier and the second inverting closed-loop amplifier are connected in series, the reference power supply is electrically connected to the input terminal of the first inverting closed-loop amplifier, the feedback circuit is electrically connected to the input terminal of the second inverting closed-loop amplifier, and the reference power supply is electrically connected to the first contact of the measuring resistor via the reference circuit.

7. The electronic load device according to claim 1, wherein the feedback circuit comprises a first operational amplifier, the first contact of the measuring resistor is electrically connected to a first input terminal of the first operational amplifier, and the fourth contact of the measuring resistor is electrically connected to a second input terminal of the first operational amplifier.

8. The electronic load device according to claim 1, wherein the feedback circuit comprises a first analog-to-digital converter, a first input terminal and a second input terminal of the first analog-to-digital converter are electrically connected to the first contact and the fourth contact of the measuring resistor, and a first output terminal of the first analog-to-digital converter is electrically connected to the reference circuit via a digital control circuit.

9. The electronic load device according to claim 8, wherein the first output of the digital control circuit and the reference power supply are electrically connected to the reference circuit via an operational amplifier.

10. The electronic load apparatus of claim 1, wherein the reference circuit is configured to control a voltage applied to the gate of the transistor based on the feedback circuit. 11 . The electronic load device according to claim 1 , wherein the first contact and the second contact of the measuring resistor are homogeneous, and the third contact and the fourth contact of the measuring resistor are homogeneous.

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