CN211375012U - A test equipment and server for input current - Google Patents

Abstract

The utility model discloses a testing device and a server for inputting current. The testing device comprises: a shunt resistor and a power supply; a first end of the shunt resistor is connected to the power supply; a second end of the shunt resistor is connected to the power supply The input end of the object to be tested; use an electric meter to measure the measurement voltage across the shunt resistor, and use Ohm's law to obtain the input current of the object to be tested according to the measurement voltage and the shunt resistance. A shunt resistor is used to form the path between the power supply and the object to be tested, and the potential difference across the shunt resistor, that is, the voltage, is measured by an ammeter. Since the resistance of the shunt resistor is known, using Ohm's law, the voltage is equal to the resistance multiplied by the current. , the current passing through the shunt resistor can be obtained, which is the input current of the DUT. Since the efficiency of the power supply is closely related to the input current, the efficiency of the power supply will only be more accurate if the input current is measured accurately.

Description

A test equipment and server for input current

technical field

The utility model relates to the technical field of electrical parameter measurement, in particular to an input current testing device and a server.

Background technique

At present, for the server motherboard, the design of the power supply is very important. When designing the power supply, it is necessary to measure the parameters of the power supply to determine whether the power supply design is correct and the quality is good, so as to meet the customer's requirements and avoid over-design.

Among them, power efficiency is the most important part of power supply design. The higher the power efficiency, the lower the power consumption, and the lower the power consumption, the more power saving. The parameters required for power supply efficiency include the output voltage, output current, input voltage, and input current of the power supply. Among them, the input current is relatively difficult to obtain accurately, therefore, the accuracy of the power efficiency is directly affected.

At present, the method of measuring the input current is to disconnect the input power path of the circuit, additionally provide the voltage and current through the DC source, connect the DC load to the output end of the DC source, and obtain the input current through the DC Power Supply Source meter. , or use the current probe (Current Probe) to obtain the input current, and obtain the power efficiency from the input current.

However, after disconnecting the input power path, additional stranded wire must be used to connect the path to use the current probe. In this way, the additional multi-core stranded wires are not easily soldered to the circuit board manually, and also cause additional impedance. Therefore, the current method often causes measurement difficulties, which is time-consuming and labor-intensive.

Utility model content

In order to solve the above technical problems existing in the prior art, the present invention provides an input current test equipment and a server, which can accurately obtain the input current of the power supply, thereby accurately obtaining the efficiency of the power supply, saving time and effort.

The present application provides an input current testing device, comprising: a shunt resistor and a power supply; a first end of the shunt resistor is connected to the power supply;

The second end of the shunt resistor is connected to the input end of the object to be tested;

The two contacts of the electric meter are respectively connected to the two ends of the shunt resistor, the measured voltage across the two ends of the shunt resistor is obtained, and the input current of the object to be tested is obtained according to the measured voltage and the shunt resistor.

Preferably, there are multiple shunt resistors, and the resistance values of the shunt resistors are different from each other; each of the shunt resistors corresponds to a controllable switch tube; the test equipment further includes: a multi-channel switch; The switch includes a static contact and a plurality of moving contacts;

The first end of each shunt resistor is connected to the power supply, the second end of each shunt resistor is connected to the first end of the corresponding controllable switch tube, and the third end of all the controllable switch tubes Both ends are connected to the input end of the object to be tested;

The control end of each controllable switch tube is respectively connected to a movable contact of the multi-way switch; the static contact of the multi-way switch is connected to the power supply.

Preferably, it also includes: a pull-up resistor;

The static contact is connected to the power source through the pull-up resistor.

Preferably, the controllable switch tube is an NMOS tube.

Preferably, the shunt resistors include the following four: a first shunt resistor, a second shunt resistor, a third shunt resistor and a fourth shunt resistor; the NMOS transistors include the following four: a first NMOS transistor, a second NMOS transistor , the third NMOS tube and the fourth NMOS tube;

The second end of the first shunt resistor is connected to the drain of the first NMOS transistor, and the source of the first NMOS transistor is connected to the input end of the object to be tested;

The second end of the second shunt resistor is connected to the drain of the second NMOS transistor, and the source of the second NMOS transistor is connected to the input end of the object to be tested;

The second end of the third shunt resistor is connected to the drain of the third NMOS transistor, and the source of the third NMOS transistor is connected to the input end of the object to be tested;

The second end of the fourth shunt resistor is connected to the drain of the fourth NMOS transistor, and the source of the fourth NMOS transistor is connected to the input end of the DUT.

Preferably, the resistance value of the first shunt resistor is 10 milliohms, the resistance value of the second shunt resistor is 5 milliohms, the resistance value of the third shunt resistor is 2 milliohms, and the resistance value of the fourth shunt resistor is 1 milliohms.

Preferably, the object to be tested is a power supply on a server motherboard.

The application also provides a server, including: a main board and the test equipment;

The test equipment is used to measure the input current of the power supply on the main board.

Compared with the prior art, the present invention has at least the following advantages:

The test equipment includes: a shunt resistor and a power supply; the first end of the shunt resistor is connected to the power supply; the second end of the shunt resistor is connected to the input end of the object to be tested; the shunt resistor is measured by an ammeter For the measurement voltage at both ends, use Ohm's law to obtain the input current of the object to be tested according to the measurement voltage and the shunt resistance.

A shunt resistor is used to form the path between the power supply and the object to be tested, and the potential difference across the shunt resistor, that is, the voltage, is measured by an ammeter. Since the resistance of the shunt resistor is known, using Ohm's law, the voltage is equal to the resistance multiplied by the current. , the current passing through the shunt resistor can be obtained, which is the input current of the DUT. Since the efficiency of the power supply is closely related to the input current, the efficiency of the power supply will be more accurate only when the input current is accurately measured.

Description of drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments described in this application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

Fig. 1 is the schematic diagram of measuring input current;

FIG. 2 is a schematic diagram of a test equipment for input current provided by the application;

3 is a schematic diagram of another input current testing equipment provided by the application;

FIG. 4 is a schematic diagram of a shunt resistance module provided by the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

Referring to Figure 1, the figure is a schematic diagram of measuring the input current.

The adjustable power supply 100 in FIG. 1 provides input current for the DUT 200 , where the DUT is a power module on the server motherboard, but not a primary power supply, but an intermediate power module. Therefore, the input current of this intermediate power module needs to be measured because the efficiency of the power module is directly related to the input current. The input current is not easy to obtain in practice. The efficiency of the power module depends on the input power and output power, and the input power depends on the input voltage and input current, and the output power depends on the output voltage and output current, among which the input current has the greatest impact on the power efficiency. How to accurately obtain the input current of the power module is introduced in the embodiment of this application. The object to be tested in this application refers to the power supply to be tested.

In the present application, the path of the input power supply is disconnected, and a shunt resistor is used to realize the current path. For details, please refer to FIG. 2 , which is a schematic diagram of an input current testing device provided by the present application.

The input current test equipment provided in this embodiment includes: a shunt resistor 300 and a power supply 100;

The first end of the shunt resistor 300 is connected to the power supply 100;

The second end of the shunt resistor 300 is connected to the input end of the object to be tested 200;

The measured voltage across the shunt resistance 300 is measured by the ammeter 400 , and the input current of the DUT 200 is obtained according to the measured voltage and the shunt resistance by using Ohm's law.

For example, the object under test 200 can be a power supply module in a server. During normal operation, the output voltage of the previous stage power supply of the power supply module is 12V, that is, the input voltage of the object under test 200 is 12V, and the input current of the object under test 200 is measured. At the time, the power supply 100 is used to provide the DUT 200 with a voltage of 12V, and the input current of the DUT 200 is measured.

In this embodiment, the shunt resistor 300 is used to optimize the accuracy of measuring the input current. The shunt resistor 300 can be selected according to the accuracy of the input current to be measured, for example, 10 milliohms, 5 milliohms, 2 milliohms or 1 milliohm can be selected. Among them, the accuracy of the input current measured corresponding to 10 milliohms is 10 times that of the input current corresponding to 1 milliohm.

The above is only a specific description, and those skilled in the art may actually need to set a specific resistance value of the shunt resistor, which is not specifically limited in this embodiment.

Among them, a multimeter (Multmeter) can be used as the electric meter.

The test equipment for input current provided in this embodiment uses a shunt resistor to form a path between the power supply and the object to be tested, and measures the potential difference between the two ends of the shunt resistor, that is, the voltage, through an ammeter. Since the resistance of the shunt resistor is known, so , using Ohm's law, the voltage is equal to the resistance multiplied by the current, and the current through the shunt resistance can be obtained, which is the input current of the object to be tested. Since the efficiency of the power supply is closely related to the input current, the efficiency of the power supply will be more accurate only when the input current is accurately measured.

The following introduces a test equipment that can include shunt resistors with various measurement accuracy, which can be switched according to the needs of the measurement accuracy, so as to obtain the input current corresponding to the accuracy requirements.

Referring to FIG. 3 , which is a schematic diagram of another input current testing device provided by the present application.

Referring to FIG. 4 , this figure is a schematic diagram of a shunt resistance module including various measurement precisions provided by the present application.

The test equipment provided in this embodiment is described below with reference to FIG. 3 and FIG. 4 . The shunt resistance module includes four shunt resistors with different resistance values as an example. It can be understood that if more kinds of measurements need to be obtained If the accuracy is higher, a larger number of shunt resistors with different resistance values can be set. The principle is the same and will not be repeated here.

There are multiple shunt resistors, and the resistance values of the shunt resistors are different; each of the shunt resistors corresponds to a controllable switch tube; the test equipment further includes: a multi-channel switch; the multi-channel switch includes a Static contacts and multiple moving contacts;

The first end of each shunt resistor is connected to the power supply, the second end of each shunt resistor is connected to the first end of the corresponding controllable switch tube, and the third end of all the controllable switch tubes Both ends are connected to the input end of the object to be tested;

The control end of each controllable switch tube is respectively connected to a movable contact of the multi-way switch; the static contact of the multi-way switch is connected to the power supply.

In addition, the test equipment provided in this embodiment may further include: a pull-up resistor;

The static contact is connected to the power source through the pull-up resistor.

In the embodiment of the present application, the controllable switch tube may be an NMOS tube, or may be other switch tubes that can implement the same principle.

The following is an example of including four shunt resistors and the controllable switch tube is an NMOS tube.

The shunt resistors include the following four: a first shunt resistor R1, a second shunt resistor R2, a third shunt resistor R3 and a fourth shunt resistor R4; the NMOS transistors include the following four: a first NMOS transistor N1, a second shunt resistor NMOS transistor N2, third NMOS transistor and fourth NMOS transistor N4;

The second end of the first shunt resistor R1 is connected to the drain of the first NN3MOS transistor N1, and the source of the first NMOS transistor N1 is connected to the input end of the DUT;

The second end of the second shunt resistor R2 is connected to the drain of the second NMOS transistor N2, and the source of the second NMOS transistor N2 is connected to the input end of the DUT;

The second end of the third shunt resistor R3 is connected to the drain of the third NMOS transistor N3, and the source of the third NMOS transistor N3 is connected to the input end of the DUT;

The second end of the fourth shunt resistor R4 is connected to the drain of the fourth NMOS transistor N4, and the source of the fourth NMOS transistor N4 is connected to the input end of the DUT.

In order to achieve four different measurement accuracies of the input current, the resistance value of the first shunt resistor R1 is 10 milliohms, the resistance value of the second shunt resistor R2 is 5 milliohms, and the resistance value of the third shunt resistor R3 is 5 milliohms. 2 milliohms and the resistance of the fourth shunt resistor R4 is 1 milliohm.

The working principle is described below in conjunction with Figure 3 and Figure 4 .

For example, when the static contact of the multiplexer S1 is connected to the first moving contact, N1 is turned on, and N2-N4 are all turned off. At this time, R1 is connected between the power supply 100 and the DUT 200 , the voltage across R1 is obtained by using the ammeter 400 , and the input current of the DUT 200 can be obtained by using the measured voltage and R1 . Similarly, when the static contact of the multi-way switch S1 is connected to the fourth moving contact, N4 is turned on, correspondingly, R4 is connected between the power supply 100 and the DUT 200. voltage, the input current of the DUT 200 can be obtained by using the measured voltage and R4.

Since the resistance values of R1 and R4 are different, the resistance value of R1 is 10 times the resistance value of R4. Therefore, the measurement accuracy of the corresponding input current when N1 is turned on is 10 times that of the corresponding input current when N4 is turned on. .

For the switching of the multi-way switch S1, the movable contact can be switched manually, or can be switched automatically through external control, which is not specifically limited in the embodiment of the present application.

In the test equipment provided by the embodiments of the present application, by setting a plurality of shunt resistors with different resistance values, they can be switched as needed, so that input currents with different precision requirements can be obtained. When the precision of the input current is high, the precise power efficiency can be obtained, which allows a more precise power supply to be set for the server.

Based on the input current testing equipment provided by the above embodiments, the embodiments of the present application further provide an input current testing method, which will be described in detail below.

The method for testing input current provided in this embodiment is applied to a testing device, where the testing device includes: a shunt resistor and an electricity meter; each of the shunt resistors has a different resistance value; the first end of the shunt resistor is connected to a power supply The second end of the shunt resistor is connected to the input end of the object to be tested; the method includes the following steps:

Use an electric meter to measure the measured voltage across the shunt resistor;

The input current of the object to be tested is obtained according to the measurement voltage and the shunt resistance using Ohm's law.

In the method provided in this embodiment, a shunt resistor is used to form the path between the power supply and the DUT, and the potential difference between the two ends of the shunt resistor, that is, the voltage, is measured by an ammeter. Since the resistance value of the shunt resistor is known, Ohm's law is used. , the voltage is equal to the resistance multiplied by the current, and the current through the shunt resistance can be obtained, which is the input current of the DUT. Since the efficiency of the power supply is closely related to the input current, the efficiency of the power supply will be more accurate only when the input current is accurately measured.

Based on the testing equipment and testing method for input current provided by the above embodiments, an embodiment of the present application further provides a server, which will be described in detail below.

The server provided by the embodiment of the present application includes: a main board and the test equipment;

The test equipment is used to measure the input current of the power supply on the main board.

Because the application speed of the server is getting higher and higher, the power supply it needs is also increasing. The larger the power supply, the more important the conversion efficiency of the power supply is. It is necessary to choose a high-efficiency power supply. First of all, it is necessary to accurately measure the precise power efficiency value before designing the power supply. The efficiency of the power supply often takes a lot of time to confirm whether the measurement is correct because the measurement error is only about 1%. The solution for accurately measuring the input current proposed by the utility model can save time and labor.

It should be understood that, in this application, "at least one (item)" refers to one or more, and "a plurality" refers to two or more. "And/or" is used to describe the relationship between related objects, indicating that there can be three kinds of relationships, for example, "A and/or B" can mean: only A, only B, and both A and B exist , where A and B can be singular or plural. The character "/" generally indicates that the associated objects are an "or" relationship. "At least one item(s) below" or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (a) of a, b or c, can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c" ", where a, b, c can be single or multiple.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art, without departing from the scope of the technical solution of the present invention, can utilize the methods and technical contents disclosed above to make many possible changes and modifications to the technical solution of the present invention, or be modified to equivalent changes. Equivalent Example. Therefore, without departing from the content of the technical solution of the present invention, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims (8)

1. A testing device for input current, comprising: a shunt resistor and a power supply; the first end of the shunt resistor is connected to the power supply; The second end of the shunt resistor is connected to the input end of the object to be tested; The two contacts of the electric meter are respectively connected to the two ends of the shunt resistor, the measured voltage across the two ends of the shunt resistor is obtained, and the input current of the object to be tested is obtained according to the measured voltage and the shunt resistor. 2 . The testing device according to claim 1 , wherein there are multiple shunt resistors, and the resistance values of the shunt resistors are different from each other; each of the shunt resistors corresponds to a controllable switch; the The test equipment also includes: a multi-way switch; the multi-way switch includes a static contact and a plurality of moving contacts; The first end of each shunt resistor is connected to the power supply, the second end of each shunt resistor is connected to the first end of the corresponding controllable switch tube, and the third end of all the controllable switch tubes Both ends are connected to the input end of the object to be tested; The control end of each controllable switch tube is respectively connected to a movable contact of the multi-way switch; the static contact of the multi-way switch is connected to the power supply. 3. The test equipment according to claim 2, further comprising: a pull-up resistor; The static contact is connected to the power source through the pull-up resistor. 4. The test equipment according to claim 2 or 3, wherein the controllable switch tube is an NMOS tube. 5. The test device according to claim 4, wherein the shunt resistor comprises the following four: a first shunt resistor, a second shunt resistor, a third shunt resistor and a fourth shunt resistor; the NMOS transistor comprises The following four: the first NMOS tube, the second NMOS tube, the third NMOS tube and the fourth NMOS tube; The second end of the first shunt resistor is connected to the drain of the first NMOS transistor, and the source of the first NMOS transistor is connected to the input end of the object to be tested; The second end of the second shunt resistor is connected to the drain of the second NMOS transistor, and the source of the second NMOS transistor is connected to the input end of the object to be tested; The second end of the third shunt resistor is connected to the drain of the third NMOS transistor, and the source of the third NMOS transistor is connected to the input end of the object to be tested; The second end of the fourth shunt resistor is connected to the drain of the fourth NMOS transistor, and the source of the fourth NMOS transistor is connected to the input end of the DUT. 6 . The test device according to claim 5 , wherein the resistance value of the first shunt resistor is 10 milliohms, the resistance value of the second shunt resistor is 5 milliohms, and the resistance value of the third shunt resistor is 5 milliohms. 7 . The resistance of 2 milliohms and the fourth shunt resistor is 1 milliohm. 7. The test equipment according to claim 2 or 3, wherein the object to be tested is a power supply on a server motherboard. 8. A server, characterized in that, comprising: a mainboard and the test equipment according to any one of claims 1-7; The test equipment is used to measure the input current of the power supply on the main board.

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