Device and method for measuring board-level chip leakage current using line impedance

Abstract

The present invention provides a device and method for measuring board-level chip leakage current using line impedance, which has a simple structure, low cost, is easy to integrate, and can accurately measure leakage current. The device of the present invention includes an electronic load module (2), a voltage amplification module (3), and a voltage measurement module (4). The method of the present invention includes the following steps: setting two measurement points in the product to be measured (1); the electronic load module applies a load current from point B and records it as I1, and simultaneously measures the voltage between measurement points A and B and records it as V1; then the electronic load module applies a load current from point B and records it as I2, and simultaneously measures the voltage between measurement points A and B and records it as V2; using the relationship between voltage, current, and resistance, the two measured current and voltage values are input into a resistance calculation formula to calculate the leakage current. The present invention can be applied to the measurement field.

Description

Technical Field

[0001] The present invention relates to the field of measurement, and in particular to a device and method for measuring leakage current of a board-level chip using line impedance. Background Art

[0002] In today's era of rapid advancements in electronic technology and the continuous innovation and evolution of electronic products, users are increasingly demanding the battery life of electronic products, but battery capacity is far from keeping up with user needs. Therefore, it is particularly important to accurately measure and control the power consumption of various components on circuit boards.

[0003] Leakage current exists in some pins of the chip, which may affect the accurate measurement of the current of a certain power consumption circuit. The leakage current cannot be ignored in the measurement of this part of the current. Therefore, some means must be used to accurately measure the size of the leakage current to ensure accurate calculation of the power consumption of the power consumption circuit.

[0004] Currently, leakage current testing often relies on instruments such as leakage testers, DMMs (digital multimeters), and SMUs (source measure units). These instruments can detect component leakage, but they are expensive, bulky, and difficult to integrate, making them challenging to scale in large-scale production. Furthermore, complex board-level circuits are often constrained by test conditions, making it difficult to measure certain leakage currents. These instruments are unable to address these specific leakage current testing challenges. This challenge is increasingly encountered during testing. To address this issue, a simple, low-cost, easily integrated device that can accurately measure leakage current is urgently needed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology and provide a device and method for measuring board-level chip leakage current using line impedance, which has a simple structure, low cost, easy integration and can accurately measure leakage current. The measurement method has simple steps, convenient operation, and does not require high-intensity labor from staff.

[0006] The technical solution adopted by the device for measuring board-level chip leakage current using line impedance of the present invention is as follows: the device includes an electronic load module that provides load current to the power supply of the product to be tested,

[0007] a voltage amplifying module that amplifies the voltage value measured between two measuring points set on the product to be tested and sends a signal to the voltage measuring module, and

[0008] a voltage measuring module that receives the signal from the voltage amplifying module and measures the voltage value between two measuring points set on the product to be tested,

[0009] The input end of the electronic load module is connected to a measuring point provided on the product to be tested, and the measuring point is connected to the negative input pole of the voltage amplification module.

[0010] Furthermore, the electronic load module includes a DC power supply, an operational amplifier comparator, a current limiting resistor, a power MOS tube and a sampling resistor. The positive electrode of the DC power supply is connected to the positive input electrode of the operational amplifier comparator, the output electrode of the operational amplifier comparator is connected to one end of the current limiting resistor, the other end of the current limiting resistor is connected to the gate of the power MOS tube, the source of the power MOS tube is connected to one end of the sampling resistor, the other end of the sampling resistor is grounded, the connection point between the source of the power MOS tube and the sampling resistor is connected to the negative input electrode of the operational amplifier comparator, and the drain of the power MOS tube is connected to a measurement point set on the product to be tested.

[0011] Furthermore, the voltage amplification module includes an operational amplifier, the positive and negative input electrodes of the operational amplifier are respectively connected to two measurement points set on the product to be tested, and the output electrode of the operational amplifier is connected to the voltage measurement module.

[0012] The voltage measurement module is an ADC module.

[0013] The method for measuring the leakage current of a board-level chip using the above-mentioned device for measuring the leakage current of a board-level chip using line impedance includes the following steps:

[0014] Step a. Set two measurement points within the product under test: Assume the product under test is equipped with a power supply, a power consumption circuit, and an integrated circuit. The power supply is connected to the power consumption circuit and the integrated circuit. The connection point between the power consumption circuit and the integrated circuit is used as measurement point B. A point on the path between the connection point between the power consumption circuit and the integrated circuit and the power supply is used as another measurement point A. Let the line impedance between measurement points A and B be Rs, and let the leakage current flowing through the integrated circuit be Ib.

[0015] Step b. Use the electronic load module to apply a load current from point B and record it as I1. At the same time, use the voltage measurement module to measure the voltage between measurement points A and B and record it as V1, and obtain the following equation 1:

[0016] Rs=V1 / (I1+Ib)…………Equation 1;

[0017] Step c. Use the electronic load module to apply a load current from point B and record it as I2. At the same time, use the voltage measurement module to measure the voltage between measurement points A and B and record it as V2, and obtain the following equation 2:

[0018] Rs=V2 / (I2+Ib)…………Equation 2;

[0019] Step d. Combine Equation 1 obtained in Step b with Equation 2 obtained in Step c, and finally calculate the leakage current Ib as:

[0020] Ib=(V1*I2-V2*I1) / (V2-V1).

[0021] The beneficial effects of the present invention are as follows: Unlike the traditional direct measurement method using expensive instruments, the present invention uses the line impedance of the PCB in combination with an electronic load module and a voltage measurement module to measure the leakage current of the chip. The electronic load module applies the load current twice to the point to be measured, and then obtains two voltage values through the voltage measurement module. The leakage current of the product to be measured can be accurately calculated using the resistance calculation formula. The entire device has a simple structure, which greatly reduces costs compared to traditional expensive instruments. It is also easier to integrate into various systems, improving integration and compatibility. This solves the problem that general instruments find it difficult to measure board-level leakage current in special scenarios. The method of the present invention is simple, easy to transplant, and highly integrated. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a simplified structural block diagram of the device of the present invention;

[0023] Figure 2 It is a simple circuit diagram inside the product to be tested;

[0024] Figure 3 1 is a simplified circuit schematic diagram of the electronic load module. DETAILED DESCRIPTION

[0025] Specific embodiments of the present invention are as follows.

[0026] The device for measuring board-level chip leakage current using line impedance of the present invention includes an electronic load module 2 for providing load current to the power supply of the product to be tested 1.

[0027] a voltage amplifying module 3 for amplifying the voltage value measured between two measuring points set on the product to be measured 1 and sending a signal to the voltage measuring module 4; and

[0028] The voltage measuring module 4 receives the signal from the voltage amplifying module 3 and measures the voltage value between two measuring points set on the product to be tested 1. The input end of the electronic load module 2 is connected to a measuring point set on the product to be tested 1, and the measuring point is connected to the negative input terminal of the voltage amplifying module 3.

[0029] The electronic load module 2 comprises a DC power supply 21, an operational amplifier comparator 22, a current-limiting resistor 23, a power MOS transistor 24, and a sampling resistor 25. The positive electrode of the DC power supply 21 is connected to the positive input of the operational amplifier comparator 22, the output of the operational amplifier comparator 22 is connected to one end of the current-limiting resistor 23, the other end of the current-limiting resistor 23 is connected to the gate of the power MOS transistor 24, the source of the power MOS transistor 24 is connected to one end of the sampling resistor 25, the other end of the sampling resistor 25 is grounded, the connection point between the source of the power MOS transistor 24 and the sampling resistor 25 is connected to the negative input of the operational amplifier comparator 22, and the drain of the power MOS transistor 24 is connected to a measurement point on the product under test 1. The voltage of the DC power supply 21 is 0-5V; the device model of the operational amplifier comparator 22 is OPA2196; and the device model of the power MOS transistor 24 is IRF1018ESPbF. In the present invention, the current of the electronic load module is denoted as Id. The electronic load module 2 provides load current to the power supply of the product under test 1 as follows: The op amp comparator 22, power MOSFET 24, and sampling resistor 25 form a negative feedback loop, adjusting the impedance of the power MOSFET 24 to ensure that the voltages at the non-inverting and inverting inputs of the op amp comparator 22 are equal. Assuming the DC power supply 21 voltage is Vx, according to the op amp virtual short circuit principle, the voltage at the inverting input of the op amp comparator 22 must also be equal to Vx. This means that the voltage across the sampling resistor 25 is also Vx, resulting in current Id = Vx / R.

[0030] The voltage amplification module 3 includes an operational amplifier 31. The positive and negative input terminals of the operational amplifier 31 are respectively connected to two measurement points provided on the product under test 1. The output terminal of the operational amplifier 31 is connected to the voltage measurement module 4. The device model of the operational amplifier 31 is ina826. The voltage measurement module 4 is an ADC module. The device model of the ADC is AD7172-2.

[0031] The method steps of the present invention are as follows.

[0032] Step a. Figure 1As shown, the power supply inside the device under test (DUT) 1 needs to read the current Is of the power consumption circuit. However, a portion of the current Ib leaks into the integrated circuit, preventing the power supply from accurately detecting Is. Therefore, the method of the present invention is used to calculate Ib to obtain Is. Two measurement points are set within DUT 1: Assume that DUT 1 is equipped with a power supply, a power consumption circuit, and an integrated circuit. The power supply is connected to the power consumption circuit and the integrated circuit. The connection point between the power consumption circuit and the integrated circuit is taken as measurement point B. A point in the path between the connection point between the power consumption circuit and the integrated circuit and the power supply is taken as another measurement point A. Let the line impedance between measurement points A and B be Rs, the voltage between the two test points be Vab, and the leakage current flowing through the integrated circuit be Ib.

[0033] Step b. Use the electronic load module 2 to apply a load current from point B and record it as I1. At the same time, the voltage between the A and B measurement points is measured by the voltage measurement module 4 and recorded as V1, and the following equation 1 is obtained:

[0034] Rs=V1 / (I1+Ib)…………Equation 1.

[0035] Step c. Then, the electronic load module 2 applies a load current from point B and records it as I2. At the same time, the voltage between the A and B measurement points is measured by the voltage measurement module 4 and recorded as V2. The following equation 2 is obtained:

[0036] Rs=V2 / (I2+Ib)…………Equation 2.

[0037] Step d. Combine Equation 1 obtained in Step b with Equation 2 obtained in Step c, and finally calculate the leakage current Ib as:

[0038] Ib=(V1*I2-V2*I1) / (V2-V1).

[0039] The device of the present invention has a simple structure, low cost, and is easy to integrate. It uses the front-end pin leakage current measurement method for chip current to accurately measure leakage current at the microampere level. In addition, the present invention has a simple principle and is easy to transplant and mass produce.

Claims

1. A method for measuring board-level chip leakage current using a device for measuring board-level chip leakage current using line impedance, characterized in that: The device includes An electronic load module (2) that provides load current to the power supply of the product under test (1), a voltage amplifying module (3) for amplifying a voltage value measured between two measuring points set on a product to be measured (1) and sending a signal to a voltage measuring module (4); and a voltage measuring module (4) that receives a signal from the voltage amplifying module (3) and measures a voltage value between two measuring points set on the product to be tested (1), The input end of the electronic load module (2) is connected to a measurement point provided on the product to be tested (1), and the measurement point is connected to the negative input terminal of the voltage amplification module (3); the method for measuring the leakage current of the board-level chip comprises the following steps: Step a. Set two measurement points in the product to be tested (1): Assume that a power supply, a power consumption circuit and an integrated circuit are provided in the product to be tested (1), the power supply is connected to the power consumption circuit and the integrated circuit, the connection point between the power consumption circuit and the integrated circuit is taken as a measurement point B, and a point on the path between the connection point between the power consumption circuit and the integrated circuit and the power supply is taken as another measurement point A, the line impedance between the measurement point A and the measurement point B is set to Rs, and the leakage current flowing through the integrated circuit is set to Ib; Step b. Use the electronic load module (2) to apply a load current from point B and record it as I1. At the same time, use the voltage measurement module (4) to measure the voltage between the AB measurement points and record it as V1, and obtain the following equation 1: Rs=V1 / (I1+Ib)…………Equation 1; Step c. Use the electronic load module (2) to apply a load current from point B and record it as I2. At the same time, use the voltage measurement module (4) to measure the voltage between the AB measurement points and record it as V2, and obtain the following equation 2: Rs=V2 / (I2+Ib)…………Equation 2; Step d. Combine Equation 1 obtained in Step b with Equation 2 obtained in Step c, and finally calculate the leakage current Ib as: Ib=(V1*I2-V2*I1) / (V2-V1).

2. The method for measuring board-level chip leakage current by using a device for measuring board-level chip leakage current using line impedance according to claim 1, characterized in that: The electronic load module (2) comprises a DC power supply (21), an operational amplifier comparator (22), a current limiting resistor (23), a power MOS tube (24) and a sampling resistor (25), wherein the positive electrode of the DC power supply (21) is connected to the positive input electrode of the operational amplifier comparator (22), the output electrode of the operational amplifier comparator (22) is connected to one end of the current limiting resistor (23), the other end of the current limiting resistor (23) is connected to the gate of the power MOS tube (24), the source electrode of the power MOS tube (24) is connected to one end of the sampling resistor (25), the other end of the sampling resistor (25) is grounded, the connection point between the source electrode of the power MOS tube (24) and the sampling resistor (25) is connected to the negative input electrode of the operational amplifier comparator (22), and the drain electrode of the power MOS tube (24) is connected to a measurement point set on the product to be tested (1).

3. The method for measuring board-level chip leakage current by using a device for measuring board-level chip leakage current using line impedance according to claim 1, characterized in that: The voltage amplification module (3) includes an operational amplifier (31), wherein the positive and negative input electrodes of the operational amplifier (31) are respectively connected to two measurement points provided on the product to be measured (1), and the output electrode of the operational amplifier (31) is connected to the voltage measurement module (4).

4. The method for measuring board-level chip leakage current by using a device for measuring board-level chip leakage current using line impedance according to claim 3, characterized in that: The voltage measurement module (4) is an ADC module.

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