Measuring device and measuring method

Abstract

Simplify the circuit. [Solution] The measuring device includes a selection unit that selects a terminal of the device to be measured and outputs the current of the selected terminal, a current detection unit that detects the current output from the selection unit, a first power supply unit that applies either a predetermined test voltage or a reference voltage to the high-potential side power supply terminal of the device to be measured, a second power supply unit that applies either a predetermined test voltage or a reference voltage to the low-potential side power supply terminal of the device to be measured, and a third power supply unit that applies either a predetermined test voltage or a reference voltage to the input terminal connected to the output of the selection unit of the current detection unit. The current detection unit detects an outflow leakage current, which is the leakage current flowing out from the terminal selected by the selection unit, an outflow correction current to correct the outflow leakage current, an inflow leakage current, which is the leakage current flowing into the terminal selected by the selection unit, and an inflow correction current to correct the inflow leakage current.

Description

Technical Field

[0001] The present disclosure relates to a measuring device and a measuring method.

Background Art

[0002] Measurement devices for measuring the leakage current (leakage current) of the terminals of a device for product inspection and the like are used. In such a measurement device, when measuring a minute leakage current, a device has been proposed that measures the leakage current of the measurement target while correcting the leakage current of its own measurement circuit (see, for example, Patent Document 1).

[0003] In this measurement device, a voltage corresponding to the leakage current of the pre-stage amplifier corresponding to the measurement circuit is held as a reference voltage and subtracted from the measurement result of the terminal current of the target device, thereby correcting the measured leakage current.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the above prior art, there is a problem that the circuit becomes complicated when applied to a device having a plurality of terminals.

[0006] Therefore, the present disclosure proposes a measuring device and a measuring method with a simplified circuit.

Means for Solving the Problems

[0007] The measuring device of the present disclosure includes: a selection unit that selects terminals of the device under test and outputs the current of the selected terminals; a current detection unit that detects the current output from the selection unit; a first power supply unit that applies either a predetermined test voltage or a reference voltage to the high-potential side power supply terminal of the device under test; a second power supply unit that applies either the predetermined test voltage or the reference voltage to the low-potential side power supply terminal of the device under test; and a third power supply unit that applies either the predetermined test voltage or the reference voltage to an input terminal connected to the output of the selection unit of the current detection unit. The current detection unit detects: an outflow leakage current which is the leakage current flowing out from the terminal selected by the selection unit; an outflow correction current for correcting the outflow leakage current; and a leakage current flowing into the terminal selected by the selection unit. The measuring device detects the incoming leakage current and the incoming correction current used to correct the incoming leakage current. The first power supply unit applies a predetermined test voltage when measuring the outgoing leakage current, the incoming leakage current, and the incoming correction current, and applies a reference voltage when measuring the outgoing correction current. The second power supply unit applies a predetermined test voltage when measuring the incoming correction current, and applies a reference voltage when measuring the outgoing leakage current, the outgoing correction current, and the incoming leakage current. The third power supply unit applies a reference voltage when measuring the outgoing leakage current and the outgoing correction current, and applies a predetermined test voltage when measuring the incoming leakage current and the incoming correction current. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows an example configuration of a measuring device according to the first embodiment of this disclosure. [Figure 2] This figure shows an example configuration of a third power supply unit according to the first embodiment of this disclosure. [Figure 3] This figure shows an example of a combination of test voltages according to the first embodiment of this disclosure. [Figure 4A] This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 4B]This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 4C] This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 4D] This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 5] This figure shows an example of a combination of test voltages according to the first embodiment of this disclosure. [Figure 6A] This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 6B] This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 6C] This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 6D] This figure shows an example of leakage current according to the first embodiment of this disclosure. [Figure 7] This figure shows an example of the processing procedure for the measurement process according to the first embodiment of this disclosure. [Figure 8] This figure shows an example of the processing procedure for detecting leakage current according to the first embodiment of this disclosure. [Figure 9] This figure shows an example of the processing procedure for the outflow correction current detection process according to the first embodiment of this disclosure. [Figure 10] This figure shows an example of the processing procedure for detecting inflow leakage current according to the first embodiment of this disclosure. [Figure 11] This figure shows an example of the processing procedure for the inflow correction current detection process according to the first embodiment of this disclosure. [Figure 12] This figure shows an example of the processing procedure for the measurement process according to the first embodiment of this disclosure. [Figure 13] This figure shows an example of the processing procedure for detecting leakage current according to the first embodiment of this disclosure. [Figure 14] This figure shows an example of the processing procedure for detecting inflow leakage current according to the first embodiment of this disclosure. [Figure 15]It is a diagram showing an example of a processing procedure for detecting an inflow correction current according to a first embodiment of the present disclosure. [Figure 16] It is a diagram showing a configuration example of a measuring device according to a second embodiment of the present disclosure. [Figure 17] It is a diagram showing a configuration example of a measuring device according to a third embodiment of the present disclosure. [Figure 18] It is a diagram showing a configuration example of a measuring device according to a fourth embodiment of the present disclosure.

Modes for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present disclosure will be described in detail based on the drawings. The description will be made in the following order. In each of the following embodiments, the same parts will be denoted by the same reference numerals, and redundant descriptions will be omitted. 1. First Embodiment 2. Second Embodiment 3. Third Embodiment 4. Fourth Embodiment

[0010] (1. First Embodiment) [Configuration of Measuring Device] FIG. 1 is a diagram showing a configuration example of a measuring device according to a first embodiment of the present disclosure. This figure is a circuit diagram showing a configuration example of the measuring device 10. The measuring device 10 is a device that measures the leakage current of the terminals of the device under measurement. The device under measurement 80 is shown in this figure. The measuring device 10 measures the leakage current of the terminals of the device under measurement 80 while supplying power to the device under measurement 80, and outputs the measurement result.

[0011] The device under measurement 80 includes an output terminal 83 that outputs a signal and an input terminal 85 to which a signal is input. The measuring device 10 measures the leakage current of these output terminal 83 and input terminal 85. Further, the device under measurement 80 includes a high-potential side power supply terminal 81 and a low-potential side power supply terminal 82 that are terminals to which power is supplied. The high-potential side power supply terminal 81 is connected to the power supply line Vdd. Also, the low-potential side power supply terminal 82 is connected to the power supply line Vss.

[0012] An output circuit is connected to output terminal 83. The output circuit in the figure consists of MOS transistors 89 and 90 and diodes 92 and 93. MOS transistors 89 and 90 constitute a complementary output circuit. Diodes 92 and 93 are protection diodes. A p-channel MOS transistor can be used for MOS transistor 89. An n-channel MOS transistor can be used for MOS transistor 90. The source of MOS transistor 89 is connected to the power line Vdd, and its drain is connected to output node 96. The source of MOS transistor 90 is connected to the power line Vss, and its drain is connected to output node 96. A drive circuit (not shown) is connected to the gates of MOS transistors 89 and 90. The cathode of diode 92 is connected to the power line Vdd, and its anode is connected to output node 96. The anode of diode 93 is connected to the power line Vss, and its cathode is connected to output node 96. Output node 96 is connected to output terminal 83.

[0013] An input circuit is connected to input terminal 85. The input circuit in the figure consists of a MOS transistor 91 and diodes 94 and 95. Diodes 94 and 95 are protection diodes. The drain of MOS transistor 91 is connected to the power line Vdd, and the source is connected to the power line Vss. A load can be connected to either the drain or the source of MOS transistor 91. The gate of MOS transistor 91 is connected to input node 97. The cathode of diode 94 is connected to the power line Vdd, and the anode is connected to input node 97. The anode of diode 95 is connected to the power line Vss, and the cathode is connected to input node 97. Input node 97 is connected to input terminal 85. An amplified signal of the input signal is generated at the drain of MOS transistor 91. Note that the configuration of the input circuit is not limited to this example. For example, a p-channel MOS transistor can be used instead of MOS transistor 91.

[0014] The measuring device 10 comprises a selection unit 20, a selection control unit 39, a current detection unit 40, a first power supply unit 50, a second power supply unit 51, a third power supply unit 52, a correction unit 60, and a control unit 70.

[0015] The selection unit 20 selects the terminals of the device under test 80. This selection unit 20 outputs the current of the selected terminal. The selection unit 20 in the figure shows an example of selecting two terminals (output terminal 83 and input terminal 85). The selection unit 20 includes input terminals 21 and 22 and output terminal 23. The power line Vddm and a common line are also connected to the selection unit 20. The circuit's reference voltage is applied to the common line. The selection unit 20 is composed of a selector 31 and diodes 24 to 29. Diodes 24 to 29 are protection diodes. For example, a 1.8V power supply is supplied to the power line Vddm.

[0016] The cathode of diode 24 is connected to the power line Vddm, and its anode is connected to input node 32. The anode of diode 25 is connected to the common line, and its cathode is connected to input node 32. The cathode of diode 26 is connected to the power line Vddm, and its anode is connected to input node 33. The anode of diode 27 is connected to the common line, and its cathode is connected to input node 33. Input node 32 is connected to input terminal 21 and input terminal (A input) of selector 31. Input node 33 is connected to input terminal 22 and input terminal (B input) of selector 31. The cathode of diode 28 is connected to the power line Vddm, and its anode is connected to output node 34. The anode of diode 29 is connected to the common line, and its cathode is connected to output node 34. Output node 34 is connected to output terminal and output terminal 23 of selector 31.

[0017] The selector 31 selects either input A or input B based on the control of the selection control unit 39.

[0018] The output terminal 83 of the device under test 80 and the input terminal 21 of the selection unit 20 are connected by wiring 13. Additionally, the input terminal 85 of the device under test 80 and the input terminal 22 of the selection unit 20 are connected by wiring 14.

[0019] The current detection unit 40 detects the current output from the selection unit 20. This current detection unit 40 can be configured using an ammeter. As shown in the figure, the current detection unit 40 is equipped with input terminals 41 and 42. The current detection unit 40 detects the current flowing between these input terminals. Input terminal 41 of the current detection unit 40 is connected to the output terminal 23 of the selection unit 20 via wiring OUT, and input terminal 42 is connected to the third power supply unit 52. The current detection unit 40 detects the current by measuring the current flowing through wiring OUT, converts it into a digital signal, and outputs it. The current detection unit 40 in the figure outputs the detected current to the correction unit 60.

[0020] As described later, the current detection unit 40 detects the outflow leakage current, which is the leakage current flowing out from the terminal selected by the selection unit 20. The current detection unit 40 also detects the outflow correction current to correct this outflow leakage current. The current detection unit 40 also detects the inflow leakage current, which is the leakage current flowing into the terminal selected by the selection unit 20. The current detection unit 40 also detects the inflow correction current to correct this inflow leakage current.

[0021] The first power supply unit 50 applies either a predetermined test voltage or a reference voltage to the high-potential side power supply terminal 81 of the device under test 80. The first power supply unit 50 can be configured, for example, as a DC power supply circuit. As will be described later, the first power supply unit 50 applies a predetermined test voltage when measuring the outflow leakage current, inflow leakage current, and inflow correction current. The first power supply unit 50 also applies a reference voltage when measuring the outflow correction current.

[0022] The second power supply unit 51 applies either a predetermined test voltage or a reference voltage to the low-potential side power supply terminal 82 of the device under test 80. The second power supply unit 51 can be configured, for example, by a DC power supply circuit. As will be described later, the second power supply unit 51 applies a predetermined test voltage when measuring the above-mentioned inflow correction current. The second power supply unit 51 also applies a reference voltage when measuring the outflow leakage current, outflow correction current, and inflow leakage current.

[0023] The third power supply unit 52 applies either a predetermined test voltage or a reference voltage to the input terminal 41 connected to the wiring OUT of the current detection unit 40. The third power supply unit 52 in the figure applies a voltage to the input terminal 42 side of the current detection unit 40 that takes into account the voltage drop due to the internal resistance of the current detection unit 40, thereby making the voltage at the input terminal 41 connected to the wiring OUT the test voltage or reference voltage. This cancels the offset voltage at the input terminal of the current detection unit 40. The third power supply unit 52 applies the reference voltage when measuring the outflow leakage current and outflow correction current described above. The third power supply unit 52 also applies a predetermined test voltage when measuring the inflow leakage current and inflow correction current. Details of the configuration of the third power supply unit 52 will be described later.

[0024] The correction unit 60 corrects the outflow leakage current based on the outflow correction current and corrects the inflow leakage current based on the inflow correction current. The correction unit 60 can correct the outflow leakage current by subtracting the outflow correction current from the outflow leakage current. The correction unit 60 can also correct the inflow leakage current by subtracting the inflow correction current from the inflow leakage current. The correction unit 60 outputs the corrected outflow leakage current and inflow leakage current to an external device.

[0025] The control unit 70 controls the entire measuring device 10. The control unit 70 controls the applied voltage to the first power supply unit 50. The control unit 70 also controls the applied voltage to the second power supply unit 51. The control unit 70 also controls the applied voltage to the third power supply unit 52. The control unit 70 also controls the current detection of the current detection unit 40.

[0026] Furthermore, the device under measurement 80, the selection unit 20, and the selection control unit 39 can be arranged on the same circuit board 12. Also, the circuit board 12 can be installed inside the constant temperature chamber 11. This reduces the number of wires leading out from the constant temperature chamber 11.

[0027] Figure 2 is a diagram showing an example configuration of a third power supply unit according to the first embodiment of the present disclosure. The same figure is a circuit diagram showing an example configuration of the third power supply unit 52. The third power supply unit 52 in the figure comprises a constant voltage circuit 53 and an operational amplifier 54. The constant voltage circuit 53 is a circuit that outputs a predetermined test voltage. This constant voltage circuit 53 generates a test voltage based on the control of the control unit 70 and supplies it to the non-inverting input terminal of the operational amplifier 54. The constant voltage circuit 53 can be configured, for example, by a DC power supply circuit. The operational amplifier 54 is controlled so that the voltage at wiring OUT and the test voltage supplied by the constant voltage circuit 53 are equal. The inverting input terminal of the operational amplifier 54 is connected to wiring OUT, and the output terminal of the operational amplifier 54 is connected to the input terminal 42 of the current detection unit 40.

[0028] Generally, the ammeter constituting the current detection unit 40 has internal resistance. This internal resistance is, for example, a shunt resistor. When input current flows through this shunt resistor, an offset voltage appears at wiring OUT. When a potential difference is generated between wiring OUT and the power line Vdd or power line Vss due to this offset voltage, a bias voltage is applied to protection diodes other than the one being measured, causing leakage current to flow. This interferes with the measurement of leakage current at the terminals of the device under test 80. Therefore, as a measure to prevent the generation of unnecessary offset voltage, a voltage-controlled voltage source as shown in the figure is applied to the third power supply unit 52, and by outputting a compensation voltage, the offset voltage generated in the current detection unit 40 can be canceled.

[0029] [Measurement of leakage current at input terminals] First, we will explain how to measure the leakage current at the input terminal 85 of the device under test 80. The leakage current is measured in four stages: Test 1 to Test 4. In Test 1, the outflow leakage current is measured. In Test 2, the outflow correction current is measured. In Test 3, the inflow leakage current is measured. In Test 4, the inflow correction current is measured.

[0030] Figure 3 shows an example of a combination of test voltages according to the first embodiment of this disclosure. The figure shows the test voltages, etc., when measuring the leakage current of the input terminal 85. In the figure, "Test" represents Test1-Test4. "Vdd" represents the test voltage applied by the first power supply unit 50 to the high-potential side power terminal 81 of the device under test 80. "Vss" represents the voltage applied by the second power supply unit 51 to the low-potential side power terminal 82 of the device under test 80. "OUT" represents the voltage applied by the third power supply unit 52 to the input terminal of the current detection unit 40. The test voltages in the figure correspond to the power supply voltage (1.8V) of the device under test 80. Also, 0V in the figure corresponds to the reference voltage.

[0031] In Test 1, the first power supply unit 50 applies 1.8V to the high-potential side power terminal 81 of the device under test 80. The second power supply unit 51 applies 0V to the low-potential side power terminal 82 of the device under test 80. The third power supply unit 52 applies 0V to the input terminal of the current detection unit 40.

[0032] In Test 2, the first power supply unit 50 applies 0V to the high-potential side power supply terminal 81 of the device under test 80. The second power supply unit 51 applies 0V to the low-potential side power supply terminal 82 of the device under test 80. The third power supply unit 52 applies 0V to the input terminal of the current detection unit 40.

[0033] In Test 3, the first power supply unit 50 applies 1.8V to the high-potential side power terminal 81 of the device under test 80. The second power supply unit 51 applies 0V to the low-potential side power terminal 82 of the device under test 80. The third power supply unit 52 applies 1.8V to the input terminal of the current detection unit 40.

[0034] In Test 4, the first power supply unit 50 applies 1.8V to the high-potential side power terminal 81 of the device under test 80. The second power supply unit 51 applies 1.8V to the low-potential side power terminal 82 of the device under test 80. The third power supply unit 52 applies 1.8V to the input terminal of the current detection unit 40.

[0035] [Leakage current] Figures 4A-4D show an example of leakage current according to the first embodiment of this disclosure. These figures represent the leakage current in Test1-Test4.

[0036] Figure 4A shows the leakage current in Test 1. As mentioned above, 1.8V is applied to the high-potential power supply terminal 81, 0V is applied to the low-potential power supply terminal 82, and 0V is applied to the wiring OUT. In this state, leakage current flows through the device under test 80 and also through the selection unit 20. The arrows in the figure represent the leakage current. A leakage current IDL1 flows from the device under test 80 to the input terminal 85. This is mainly due to the leakage current of diode 94. A leakage current IML1 flows from the input node 33 of the selection unit 20. This is mainly due to diode 26. A leakage current IML2 flows from the output terminal 23 of the selection unit 20. This is mainly due to diode 28. The total current IDL1 + IML1 + IML2 flows through the wiring OUT. The current detection unit 40 detects this current as a leakage current.

[0037] Figure 4B shows the leakage current in Test 2. As described above, 0V is applied to the high-potential power supply terminal 81, 0V is applied to the low-potential power supply terminal 82, and 0V is applied to the wiring OUT. In this state, leakage current (IML1 and IML2) flows only to the selection unit 20. The current IML1 + IML2 flows to the wiring OUT. The current detection unit 40 detects this current as the leakage correction current.

[0038] Figure 4C shows the leakage current in Test 3. As mentioned above, 1.8V is applied to the high-potential power supply terminal 81, 0V is applied to the low-potential power supply terminal 82, and 1.8V is applied to the wiring OUT. In this state, leakage current flows through the device under test 80 and the selection unit 20. A leakage current IDL2 flows into the device under test 80 at the input terminal 85. This is mainly due to the leakage current of diode 95. A leakage current IML3 flows through the input node 33 of the selection unit 20. This is mainly due to diode 27. A leakage current IML4 flows through the output terminal 23 of the selection unit 20. This is mainly due to diode 29. The currents -IDL2-IML3-IML4 flow through the wiring OUT. The current detection unit 40 detects this current as an inflowing leakage current.

[0039] Figure 4D shows the leakage current in Test 4. As mentioned above, 1.8V is applied to the high-potential power supply terminal 81, 1.8V is applied to the low-potential power supply terminal 82, and 1.8V is applied to the wiring OUT. In this state, leakage current (IML3 and IML4) flows only to the selection unit 20. A current of -IML3-IML4 flows to the wiring OUT. The current detection unit 40 detects this current as the inflow correction current.

[0040] The outflow correction current is the leakage current caused by the selection unit 20 and corresponds to the error included in the outflow leakage current. The outflow leakage current can be corrected by subtracting the outflow correction current from the outflow leakage current. Similarly, the inflow correction current is the leakage current caused by the selection unit 20 and corresponds to the error included in the inflow leakage current. The inflow leakage current can be corrected by subtracting the inflow correction current from the inflow leakage current. The correction unit 60 described above performs the correction in this manner.

[0041] [Measurement of leakage current at output terminals] Next, we will explain how to measure the leakage current at the output terminal 83 of the device under test 80. Similar to the measurement of the leakage current at the input terminal 85, Test1 measures the outflow leakage current, Test2 measures the outflow correction current, Test3 measures the inflow leakage current, and Test4 measures the inflow correction current.

[0042] Figure 5 shows an example of a test voltage combination according to the first embodiment of this disclosure. The figure shows the test voltage when measuring the leakage current at the output terminal 83. The test voltage in the figure is a voltage lower than the power supply voltage of the device under test 80. Under normal operating conditions of the device under test 80, some signal is output from the output terminal 83, which interferes with the measurement of the leakage current. Therefore, a voltage sufficiently lower than the power supply voltage of the device under test 80 is applied to prevent signal output from the output terminal 83. In the figure, a test voltage of 0.1V is applied.

[0043] In Test 1, the first power supply unit 50 applies 0.1V to the high-potential side power supply terminal 81 of the device under test 80. The second power supply unit 51 applies 0V to the low-potential side power supply terminal 82 of the device under test 80. The third power supply unit 52 applies 0V to the input terminal of the current detection unit 40.

[0044] In Test 2, the first power supply unit 50 applies 0V to the high-potential side power supply terminal 81 of the device under test 80. The second power supply unit 51 applies 0V to the low-potential side power supply terminal 82 of the device under test 80. The third power supply unit 52 applies 0V to the input terminal of the current detection unit 40.

[0045] In Test 3, the first power supply unit 50 applies 0.1V to the high-potential side power supply terminal 81 of the device under test 80. The second power supply unit 51 applies 0V to the low-potential side power supply terminal 82 of the device under test 80. The third power supply unit 52 applies 0.1V to the input terminal of the current detection unit 40.

[0046] In Test 4, the first power supply unit 50 applies 0.1V to the high-potential side power supply terminal 81 of the device under test 80. The second power supply unit 51 applies 0.1V to the low-potential side power supply terminal 82 of the device under test 80. The third power supply unit 52 applies 0.1V to the input terminal of the current detection unit 40.

[0047] [Leakage current] Figures 6A-6D show an example of leakage current according to the first embodiment of this disclosure. These figures represent the leakage current in Test1-Test4.

[0048] Figure 6A shows the leakage current in Test 1. As mentioned above, 0.1V is applied to the high-potential power supply terminal 81, 0V is applied to the low-potential power supply terminal 82, and 0V is applied to the wiring OUT. In this state, leakage current flows through the device under test 80 and the selection unit 20. Leakage current IDL1 flows through the input terminal 85 of the device under test 80. Leakage current IML1 flows through the input node 32 of the selection unit 20. Leakage current IML2 flows through the output terminal 23 of the selection unit 20. The current IDL1 + IML1 + IML2 flows through the wiring OUT. The current detection unit 40 detects this current as a leakage current.

[0049] Figure 6B shows the leakage current in Test 2. As described above, 0V is applied to the high-potential power supply terminal 81, 0V is applied to the low-potential power supply terminal 82, and 0V is applied to the wiring OUT. In this state, leakage current (IML1 and IML2) flows only to the selection unit 20. The current IML1 + IML2 flows to the wiring OUT. The current detection unit 40 detects this current as the leakage correction current.

[0050] Figure 6C shows the leakage current in Test 3. As mentioned above, 0.1V is applied to the high-potential power supply terminal 81, 0V is applied to the low-potential power supply terminal 82, and 0.1V is applied to the wiring OUT. In this state, leakage current flows through the device under test 80 and the selection unit 20. Leakage current IDL2 flows through the input terminal 85 of the device under test 80. Leakage currents IML1 and IML3 flow through the input node 32 of the selection unit 20. Leakage currents IML2 and IML4 flow through the output terminal 23 of the selection unit 20. Therefore, a current of -IDL2+IML1+IML2-IML3-IML4 flows through the wiring OUT. The current detection unit 40 detects this current as inflow leakage current.

[0051] Figure 6D shows the leakage current in Test 4. As mentioned above, 0.1V is applied to the high-potential power supply terminal 81, 0.1V is applied to the low-potential power supply terminal 82, and 0.1V is applied to the wiring OUT. In this state, leakage current (IML1-IML4) flows only through the selection unit 20. Current IML1+IML2-IML3-IML4 flows through the wiring OUT. The current detection unit 40 detects this current as the inflow correction current.

[0052] Similar to the measurement of leakage current at input terminal 85, the outflow leakage current can be corrected by subtracting the outflow correction current from the outflow leakage current. Similarly, the inflow leakage current can be corrected by subtracting the inflow correction current from the inflow leakage current. The correction unit 60 described above performs the correction in this manner.

[0053] [Measurement process for leakage current at input terminals] Figure 7 is a diagram showing an example of the processing procedure for the measurement process according to the first embodiment of this disclosure. The same figure is a flowchart showing an example of the measurement process for leakage current at the input terminal in the measuring device 10.

[0054] First, the selection control unit 39 causes the selection unit 20 to select the input terminal (input terminal 85) of the device under test 80 (step S101). Next, the outflow leakage current detection process (1) (step S110) is performed to obtain the outflow leakage current of the input terminal. Next, the outflow correction current detection process (step S120) is performed to obtain the outflow correction current of the input terminal. Next, the correction unit 60 corrects the outflow leakage current based on the outflow correction current (step S102). Next, the inflow leakage current detection process (1) (step S130) is performed to obtain the inflow leakage current of the input terminal. Next, the inflow correction current detection process (1) (step S140) is performed to obtain the inflow correction current of the input terminal. Next, the correction unit 60 corrects the inflow leakage current based on the inflow correction current (step S103).

[0055] [Leakage current detection process] Figure 8 is a diagram showing an example of the processing procedure for detecting leakage current flowing out according to the first embodiment of this disclosure. This figure is a flowchart showing an example of the process in step S110 in Figure 7. First, the first power supply unit 50 applies a power supply voltage (1.8V) to the high-potential side power supply terminal 81 of the device under test 80 (step S111). Next, the second power supply unit 51 applies a reference voltage (0V) to the low-potential side power supply terminal 82 of the device under test 80 (step S112). Next, the third power supply unit 52 applies a reference voltage to the input terminal of the current detection unit 40 (step S113). Next, the current detection unit 40 detects the leakage current flowing out (step S114). After that, the process returns to the original state.

[0056] [Current flow correction detection process] Figure 9 is a diagram showing an example of the processing procedure for the outflow correction current detection process according to the first embodiment of this disclosure. This figure is a flowchart showing an example of the process in step S120 in Figure 7. First, the first power supply unit 50 applies a reference voltage to the high-potential side power supply terminal 81 of the device under test 80 (step S121). Next, the second power supply unit 51 applies a reference voltage to the low-potential side power supply terminal 82 of the device under test 80 (step S122). Next, the third power supply unit 52 applies a reference voltage to the input terminal of the current detection unit 40 (step S123). Next, the current detection unit 40 detects the outflow correction current (step S124). After that, the process returns to the original state.

[0057] [Inflow leakage current detection process] Figure 10 is a diagram showing an example of the processing procedure for inflow leakage current detection processing according to the first embodiment of this disclosure. The same figure is a flowchart showing an example of the processing in step S130 in Figure 7. First, the first power supply unit 50 applies a power supply voltage to the high-potential side power supply terminal 81 of the device under test 80 (step S131). Next, the second power supply unit 51 applies a reference voltage to the low-potential side power supply terminal 82 of the device under test 80 (step S132). Next, the third power supply unit 52 applies a power supply voltage to the input terminal of the current detection unit 40 (step S133). Next, the current detection unit 40 detects the inflow leakage current (step S134). After that, the process returns to the original state.

[0058] [Current inflow correction detection process] Figure 11 is a diagram showing an example of the processing procedure for the inflow correction current detection process according to the first embodiment of this disclosure. The same figure is a flowchart showing an example of the process in step S140 in Figure 7. First, the first power supply unit 50 applies a power supply voltage to the high-potential side power supply terminal 81 of the device under test 80 (step S141). Next, the second power supply unit 51 applies a power supply voltage to the low-potential side power supply terminal 82 of the device under test 80 (step S142). Next, the third power supply unit 52 applies a power supply voltage to the input terminal of the current detection unit 40 (step S143). Next, the current detection unit 40 detects the inflow correction current (step S144). After that, the process returns to the original state.

[0059] [Measurement process for leakage current at output terminals] Figure 12 is a diagram showing an example of the processing procedure for the measurement process according to the first embodiment of this disclosure. The same figure is a flowchart showing an example of the measurement process for leakage current at the output terminal of the measuring device 10.

[0060] First, the selection control unit 39 causes the selection unit 20 to select the output terminal (output terminal 83) of the device under test 80 (step S151). Next, the outflow leakage current detection process (2) (step S160) is performed to obtain the outflow leakage current of the output terminal. Next, the outflow correction current detection process (step S120) is performed to obtain the outflow correction current of the output terminal. Next, the correction unit 60 corrects the outflow leakage current based on the outflow correction current (step S152). Next, the inflow leakage current detection process (2) (step S180) is performed to obtain the inflow leakage current of the output terminal. Next, the inflow correction current detection process (2) (step S190) is performed to obtain the inflow correction current of the output terminal. Next, the correction unit 60 corrects the inflow leakage current based on the inflow correction current (step S153).

[0061] [Leakage current detection process] Figure 13 is a diagram showing an example of the processing procedure for detecting leakage current flowing out according to the first embodiment of this disclosure. The same figure is a flowchart showing an example of the process in step S160 in Figure 12. First, the first power supply unit 50 applies a test voltage (0.1V) to the high-potential side power supply terminal 81 of the device under test 80 (step S161). Next, the second power supply unit 51 applies a reference voltage to the low-potential side power supply terminal 82 of the device under test 80 (step S162). Next, the third power supply unit 52 applies a reference voltage to the input terminal of the current detection unit 40 (step S163). Next, the current detection unit 40 detects the leakage current flowing out (step S164). After that, the process returns to the original state.

[0062] [Inflow leakage current detection process] Figure 14 is a diagram showing an example of the processing procedure for inflow leakage current detection processing according to the first embodiment of this disclosure. The same figure is a flowchart showing an example of the processing in step S180 in Figure 12. First, the first power supply unit 50 applies a test voltage to the high-potential side power supply terminal 81 of the device under test 80 (step S181). Next, the second power supply unit 51 applies a reference voltage to the low-potential side power supply terminal 82 of the device under test 80 (step S182). Next, the third power supply unit 52 applies a test voltage to the input terminal of the current detection unit 40 (step S183). Next, the current detection unit 40 detects the inflow leakage current (step S184). After that, the process returns to the original state.

[0063] [Current inflow correction detection process] Figure 15 is a diagram showing an example of the processing procedure for the inflow correction current detection process according to the first embodiment of this disclosure. The same figure is a flowchart showing an example of the process in step S190 in Figure 12. First, the first power supply unit 50 applies a test voltage to the high-potential side power supply terminal 81 of the device under test 80 (step S191). Next, the second power supply unit 51 applies a test voltage to the low-potential side power supply terminal 82 of the device under test 80 (step S192). Next, the third power supply unit 52 applies a test voltage to the input terminal of the current detection unit 40 (step S193). Next, the current detection unit 40 detects the inflow correction current (step S194). After that, the process returns to the original state.

[0064] Thus, in the first embodiment of the present disclosure, the measuring device 10 measures the leakage current while the selection unit 20 selects the terminals of the device to be measured 80, and corrects the error based on the leakage current of the selection unit 20. This makes it possible to simplify the measuring device 10.

[0065] (2. Second Embodiment) The measuring device 10 of the first embodiment described above measured the leakage current of the input terminal 85 and output terminal 83 of the device under test 80. In contrast, the measuring device 10 of the second embodiment of this disclosure differs from the first embodiment described above in that it measures the leakage current of the input and output terminals of the device under test 80.

[0066] [Configuration of the measuring device] Figure 16 is a diagram showing an example configuration of a measuring device according to the second embodiment of this disclosure. Similar to Figure 1, this figure is a circuit diagram showing an example configuration of the measuring device 10. Note that in this figure, descriptions other than the device to be measured 80 and the selection unit 20 have been omitted.

[0067] The device under test 80 in the figure is equipped with an input / output terminal 86. This input / output terminal 86 is a terminal that performs both signal input and signal output. The output node 96 connected to the input / output terminal 86 is connected to the input circuit and output circuit described in Figure 1.

[0068] The input terminal 21 of the selection unit 20 in the figure is connected to the input / output terminal 86 of the device under test 80. Leakage current can be measured using the method shown in Figures 5 to 6A-6D. Alternatively, the same process as the leakage current measurement process in Figure 7 can be applied.

[0069] The configuration of the measuring device 10 other than that described above is the same as that of the measuring device 10 in the first embodiment of this disclosure, so a description will be omitted.

[0070] Thus, the measuring device 10 of the second embodiment of this disclosure can detect leakage current at the input / output terminals 86 of the device under measurement 80.

[0071] (3. Third Embodiment) The measuring device 10 of the first embodiment described above used a two-input selection unit 20. In contrast, the measuring device 10 of the third embodiment of this disclosure differs from the first embodiment described above in that it uses a selection unit 20 with three or more inputs.

[0072] [Configuration of the measuring device] Figure 17 is a diagram showing an example configuration of a measuring device according to the third embodiment of this disclosure. Similar to Figure 1, this figure is a circuit diagram showing an example configuration of the measuring device 10. Note that in this figure, descriptions other than the device to be measured 80 and the selection unit 20 have been omitted. The measuring device 10 in this figure differs from the measuring device 10 in Figure 1 in that the device to be measured 80 is equipped with input terminals 85a and 85b and output terminals 83a and 83b, and the selection unit 20 is equipped with four input terminals (input terminals 21a, 21b, 22a and 22b).

[0073] The selection unit 20 includes selectors 31a, 31b, and 31c. Input terminal 21a of the selection unit 20 is connected to output terminal 83a of the device under test 80. Input terminal 22a of the selection unit 20 is connected to input terminal 85a of the device under test 80. Input terminal 21b of the selection unit 20 is connected to output terminal 83b of the device under test 80. Input terminal 22b of the selection unit 20 is connected to input terminal 85b of the device under test 80.

[0074] The input terminals 21a and 22a of the selection unit 20 are connected to the selector 31a. The input terminals 21b and 22b of the selection unit 20 are connected to the selector 31b. The output terminals of selector 31a and selector 31b are connected to the inputs of selector 31c, respectively.

[0075] The configuration of the measuring device 10 other than that described above is the same as that of the measuring device 10 in the first embodiment of this disclosure, so a description will be omitted.

[0076] Thus, the measuring device 10 of the third embodiment of this disclosure uses a selection unit 20 that combines multiple selectors. This makes it possible to accommodate a device to be measured 80 having a large number of terminals.

[0077] (4. Fourth Embodiment) The measuring device 10 of the third embodiment described above used a selection unit 20 having multiple selectors. In contrast, the measuring device 10 of the fourth embodiment of this disclosure differs from the third embodiment described above in that it includes multiple selection units 20.

[0078] [Configuration of the measuring device] Figure 18 is a diagram showing an example configuration of a measuring device according to the fourth embodiment of this disclosure. Similar to Figure 17, this figure is a circuit diagram representing an example configuration of the measuring device 10. The measuring device 10 in this figure differs from the measuring device 10 in Figure 17 in that it comprises a plurality of selection units 20.

[0079] The measuring device 10 in the figure comprises selection units 20a, 20b, and 20c. Selection unit 20a comprises input terminals 21a and 22a. These input terminals 21a and 22a are connected to the output terminals 83a and 85a of the device under test 80, respectively. Selection unit 20b comprises input terminals 21b and 22b. These input terminals 21b and 22b are connected to the output terminals 83b and 85b of the device under test 80, respectively. The output terminals of selection unit 20a and selection unit 20b are connected to the inputs of selection unit 20c, respectively.

[0080] In the measuring device 10 shown in the figure, the number of selection units 20 increases, and therefore the leakage current caused by the selection units 20 also increases. However, by applying the methods shown in Figures 3 and 4A-4D and Figures 5 and 6A-6D, the accuracy of leakage current detection can be improved.

[0081] The configuration of the measuring device 10 other than that described above is the same as that of the measuring device 10 in the third embodiment of this disclosure, so a description will be omitted.

[0082] Thus, the measuring device 10 of the fourth embodiment of this disclosure uses a plurality of selection units 20. This makes it possible to accommodate a device to be measured 80 having a large number of terminals.

[0083] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.

[0084] Some examples of the combinations of technical features that will be disclosed are listed below. (1) A selection unit that selects a terminal of the device under test and outputs the current from the selected terminal, A current detection unit for detecting the current output from the selection unit, A first power supply unit that applies either a predetermined test voltage or a reference voltage to the high-potential side power supply terminal of the device under test, A second power supply unit that applies either the predetermined test voltage or the reference voltage to the low-potential power supply terminal of the device under test, A third power supply unit that applies either the predetermined test voltage or the reference voltage to the input terminal connected to the output of the selection unit of the current detection unit. It has, The current detection unit detects an outflow leakage current, which is the leakage current flowing out from the terminal selected by the selection unit; an outflow correction current for correcting the outflow leakage current; an inflow leakage current, which is the leakage current flowing into the terminal selected by the selection unit; and an inflow correction current for correcting the inflow leakage current. The first power supply unit applies the predetermined test voltage when measuring the outflow leakage current, the inflow leakage current, and the inflow correction current, and applies the reference voltage when measuring the outflow correction current. The second power supply unit applies the predetermined test voltage when measuring the inflow correction current, and applies the reference voltage when measuring the outflow leakage current, the outflow correction current, and the inflow leakage current. The third power supply unit applies the reference voltage when measuring the outflow leakage current and the outflow correction current, and applies the predetermined test voltage when measuring the inflow leakage current and the inflow correction current. Measuring device. (2) The measuring device according to (1), further comprising a correction unit that corrects the outflow leakage current based on the outflow correction current and corrects the inflow leakage current based on the inflow correction current. (3) The measuring device according to (2), wherein the correction unit corrects the outflow leakage current by subtracting the outflow correction current from the outflow leakage current and corrects the inflow leakage current by subtracting the inflow correction current from the inflow leakage current. (4) The first power supply unit applies the test voltage, which is a voltage corresponding to the power supply voltage of the device under test, when the selection unit selects the input terminal of the device under test. The second power supply unit applies the test voltage, which is a voltage corresponding to the power supply voltage of the device under test, when the selection unit selects the input terminal of the device under test. The third power supply unit applies the test voltage, which is a voltage corresponding to the power supply voltage of the device under test, when the selection unit selects the input terminal of the device under test. A measuring device as described in any of (1) to (3) above. (5) The first power supply unit applies a test voltage that is less than the power supply voltage of the device under test when the selection unit selects the output terminal of the device under test. The second power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the output terminal of the device under test. The third power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the output terminal of the device under test. A measuring device as described in any of (1) to (3) above. (6) The first power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the input / output terminals of the device under test. The second power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the input / output terminals of the device under test. The third power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the input / output terminals of the device under test. A measuring device as described in any of (1) to (3) above. (7) The selection unit is a measuring device according to any one of (1) to (6) above, which is arranged on the same substrate as the instrument to be measured. (8) The selection unit is a measuring device according to any one of (1) to (7) above, which is placed in the same constant temperature bath as the instrument to be measured. (9) The measuring device according to any one of (1) to (8), further comprising a control unit for controlling the current detection unit, the first power supply unit, the second power supply unit, and the third power supply unit. (10) A measuring device comprising: a selection unit that selects a terminal of the device under test and outputs a current from the selected terminal; a current detection unit that detects the current output from the selection unit; a first power supply unit that applies either a predetermined test voltage or a reference voltage to the high-potential side power supply terminal of the device under test; a second power supply unit that applies either the predetermined test voltage or the reference voltage to the low-potential side power supply terminal of the device under test; and a third power supply unit that applies either the predetermined test voltage or the reference voltage to an input terminal connected to the output of the selection unit of the current detection unit, The system detects the outflow leakage current, which is the leakage current flowing out from the terminal selected by the selection unit, To detect a leakage current for correcting the aforementioned leakage current, The system detects the inflow leakage current, which is a leakage current flowing into the terminal selected by the selection unit, To detect an inflow correction current for correcting the aforementioned inflow leakage current, When measuring the outflow leakage current, the inflow leakage current, and the inflow correction current, the predetermined test voltage is applied to the high-potential side power supply terminal of the device under test, When measuring the aforementioned flow correction current, the reference voltage is applied to the high-potential side power supply terminal of the device under test, When measuring the inflow correction current, the predetermined test voltage is applied to the low-potential side power supply terminal of the device under test, When measuring the outflow leakage current, the outflow correction current, and the inflow leakage current, the reference voltage is applied to the low-potential side power supply terminal of the device under test, When measuring the aforementioned leakage current and the leakage correction current, the reference voltage is applied to the input terminal connected to the output of the selection unit of the current detection unit, When measuring the inflow leakage current and the inflow correction current, the predetermined test voltage is applied to the input terminal connected to the output of the selection unit of the current detection unit. A measurement method that includes [details omitted]. [Explanation of Symbols]

[0085] 10 Measuring device 11 Temperature bath 12 circuit boards 20, 20a, 20b, 20c Selection section 39 Selection Control Unit 40 Current detection unit 50 First power supply unit 51 Second power supply unit 52 Third power supply unit 60 Correction section 70 Control Unit 80 Equipment under test 81 High potential side power supply terminal 82 Low potential side power supply terminal 83, 83a, 83b output terminals 41, 42, 85, 85a, 85b Input terminals

Claims

1. A selection unit that selects a terminal of the device under test and outputs the current from the selected terminal, A current detection unit for detecting the current output from the selection unit, A first power supply unit that applies either a predetermined test voltage or a reference voltage to the high-potential side power supply terminal of the device under test, A second power supply unit that applies either the predetermined test voltage or the reference voltage to the low-potential side power supply terminal of the device under test, A third power supply unit that applies either the predetermined test voltage or the reference voltage to the input terminal connected to the output of the selection unit of the current detection unit. It has, The current detection unit detects an outflow leakage current, which is the leakage current flowing out from the terminal selected by the selection unit; an outflow correction current for correcting the outflow leakage current; an inflow leakage current, which is the leakage current flowing into the terminal selected by the selection unit; and an inflow correction current for correcting the inflow leakage current. The first power supply unit applies the predetermined test voltage when measuring the outflow leakage current, the inflow leakage current, and the inflow correction current, and applies the reference voltage when measuring the outflow correction current. The second power supply unit applies the predetermined test voltage when measuring the inflow correction current, and applies the reference voltage when measuring the outflow leakage current, the outflow correction current, and the inflow leakage current. The third power supply unit applies the reference voltage when measuring the outflow leakage current and the outflow correction current, and applies the predetermined test voltage when measuring the inflow leakage current and the inflow correction current. Measuring device.

2. The measuring device according to claim 1, further comprising a correction unit that corrects the outflow leakage current based on the outflow correction current and corrects the inflow leakage current based on the inflow correction current.

3. The measuring device according to claim 2, wherein the correction unit corrects the outflow leakage current by subtracting the outflow correction current from the outflow leakage current and corrects the inflow leakage current by subtracting the inflow correction current from the inflow leakage current.

4. The first power supply unit applies the test voltage, which is a voltage corresponding to the power supply voltage of the device under test, when the selection unit selects the input terminal of the device under test. The second power supply unit applies the test voltage, which is a voltage corresponding to the power supply voltage of the device under test, when the selection unit selects the input terminal of the device under test. The third power supply unit applies the test voltage, which is a voltage corresponding to the power supply voltage of the device under test, when the selection unit selects the input terminal of the device under test. A measuring device according to any one of claims 1 to 3.

5. The first power supply unit applies a test voltage that is less than the power supply voltage of the device under test when the selection unit selects the output terminal of the device under test. The second power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the output terminal of the device under test. The third power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the output terminal of the device under test. A measuring device according to any one of claims 1 to 3.

6. The first power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the input / output terminals of the device under test. The second power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the input / output terminals of the device under test. The third power supply unit applies the test voltage, which is less than the power supply voltage of the device under test, when the selection unit selects the input / output terminals of the device under test. A measuring device according to any one of claims 1 to 3.

7. The measuring device according to any one of claims 1 to 3, wherein the selection unit is arranged on the same substrate as the instrument to be measured.

8. The measuring device according to any one of claims 1 to 3, wherein the selection unit is arranged in the same constant temperature bath as the instrument to be measured.

9. The measuring device according to any one of claims 1 to 3, further comprising a control unit for controlling the current detection unit, the first power supply unit, the second power supply unit, and the third power supply unit.

10. A measuring device comprising: a selection unit that selects a terminal of the device under test and outputs the current of the selected terminal; a current detection unit that detects the current output from the selection unit; a first power supply unit that applies either a predetermined test voltage or a reference voltage to the high-potential side power supply terminal of the device under test; a second power supply unit that applies either the predetermined test voltage or the reference voltage to the low-potential side power supply terminal of the device under test; and a third power supply unit that applies either the predetermined test voltage or the reference voltage to the input terminal connected to the output of the selection unit of the current detection unit, The system detects the outflow leakage current, which is the leakage current flowing out from the terminal selected by the selection unit, To detect a leakage current for correcting the aforementioned leakage current, The system detects the inflow leakage current, which is a leakage current flowing into the terminal selected by the selection unit, To detect an inflow correction current for correcting the aforementioned inflow leakage current, When measuring the outflow leakage current, the inflow leakage current, and the inflow correction current, the predetermined test voltage is applied to the high-potential side power supply terminal of the device under test, When measuring the aforementioned flow correction current, the reference voltage is applied to the high-potential side power supply terminal of the device under test, When measuring the inflow correction current, the predetermined test voltage is applied to the low-potential side power supply terminal of the device under test, When measuring the outflow leakage current, the outflow correction current, and the inflow leakage current, the reference voltage is applied to the low-potential side power supply terminal of the device under test. When measuring the aforementioned leakage current and the leakage correction current, the reference voltage is applied to the input terminal connected to the output of the selection unit of the current detection unit, When measuring the inflow leakage current and the inflow correction current, the predetermined test voltage is applied to the input terminal connected to the output of the selection unit of the current detection unit. Measurement methods including

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