CN114546016B

CN114546016B - Test equipment

Info

Publication number: CN114546016B
Application number: CN202210442595.0A
Authority: CN
Inventors: 张博佳
Original assignee: Wuhan Jingce Electronic Group Co Ltd; Wuhan Jingli Electronic Technology Co Ltd
Current assignee: Wuhan Jingce Electronic Group Co Ltd; Wuhan Jingli Electronic Technology Co Ltd
Priority date: 2022-04-26
Filing date: 2022-04-26
Publication date: 2022-08-05
Anticipated expiration: 2042-04-26
Also published as: CN114546016A

Abstract

The invention discloses a test device. The test apparatus includes: power module, voltage follower circuit and signal level converting circuit, the input of voltage follower circuit with the output electricity of power module is connected, in order to receive the required VDDIO voltage of equipment to be tested that the power module provided, the output of voltage follower circuit with the voltage input electricity of signal level converting circuit is connected, and the output voltage of voltage follower circuit follows the input the change of VDDIO voltage and change. According to the VDDIO voltage detection circuit, the hardware circuit of the test equipment is improved, and on the premise that the IO channel communication is established between the test equipment and the equipment to be tested, the voltage follower circuit is used for supplying power to the signal level conversion circuit along with the VDDIO voltage, so that the original VDDIO voltage is not consumed, the current, the energy consumption and the like of the equipment to be tested are measured more accurately, and software algorithm correction is not needed.

Description

Test equipment

Technical Field

The application relates to the technical field of testing, in particular to a testing device.

Background

At present, when a test device and a product to be tested are tested, the test product is generally required to be controlled to enter various different working modes, and the same test device is often compatible with various different devices to be tested. The basic requirement for establishing communication between the test device and the device to be tested through the IO channel is that the IO power supply voltages of the test device and the device to be tested are the same, and the IO power supply voltage provided to the device to be tested is also referred to as VDDIO voltage. VDDIO voltage of the equipment to be tested is provided by the measuring equipment, IO pin output of MCU (control chip) in the measuring equipment is usually 3.3V, also be the standard LVCMOS level, but VDDIO voltage that the equipment to be tested can accept is generally less than 3.3V, and VDDIO voltage of each kind of equipment to be tested is often also different, so in order to enable the testing equipment to be compatible with various products, all can built-in signal level conversion circuit in the testing equipment, conveniently switch in the product to be tested after the IO control signal is converted into VDDIO voltage that the equipment to be tested needs.

At present, when various modules or other low-power-consumption products in a mobile phone are detected, the current consumption of an IO module circuit in equipment to be detected can be measured. However, there is a problem that the VDDIO test current is large when measuring this value. The traditional solution of the test equipment for VDDIO test current is that after the product is finished, later stage software calibration is carried out on different products to be tested or auxiliary calibration is carried out by means of other calibration instruments, so that the power consumption of the actually measured current of the test equipment VDDIO is close to 0, the later stage calibration mode needs complex algorithm optimization and nonlinear conditions can occur, for example, when the IO communication rate of the equipment is low, the total VDDIO current after the equipment calibration is almost equal to the current value of the test product, but when the IO communication rate is high, the current consumption of a level conversion circuit is increased, so that the actual VDDIO current of the test product can deviate from the test value of the test equipment, and the judgment of the test result is influenced.

Disclosure of Invention

Aiming at least one defect or improvement requirement in the prior art, the invention provides the test equipment, which can accurately measure the current, the energy consumption and the like of the equipment to be tested on the premise of ensuring that the communication is established between the test equipment and the equipment to be tested through the IO channel, and does not need to carry out software algorithm correction.

To achieve the above object, the present invention provides a test apparatus comprising: power module, voltage follower circuit and signal level converting circuit, the input of voltage follower circuit with the output electricity of power module is connected, in order to receive the required VDDIO voltage of equipment to be tested that the power module provided, the output of voltage follower circuit with the voltage input electricity of signal level converting circuit is connected, and the output voltage of voltage follower circuit follows the input the change of VDDIO voltage and change.

Furthermore, the test equipment also comprises a control module, and a control signal input end of the signal level conversion circuit is electrically connected with the control module.

Further, the signal level conversion circuit converts the standard level control signal input by the control module into a control signal of a level required by the device to be tested based on the output voltage of the voltage follower circuit, and outputs the control signal to the device to be tested.

Further, the voltage follower circuit comprises an operational amplifier and an N-channel MOS transistor, wherein the non-inverting input terminal of the operational amplifier is electrically connected with the output terminal of the power module to receive the VDDIO voltage provided by the power module, the output terminal of the operational amplifier is electrically connected with the gate of the N-channel MOS transistor, the drain of the N-channel MOS transistor is used for inputting the excitation voltage with the preset amplitude, and the source of the N-channel MOS transistor is electrically connected with the inverting input terminal of the operational amplifier.

Further, the voltage follower circuit includes an operational amplifier and an NPN triode, a non-inverting input terminal of the operational amplifier is electrically connected to an output terminal of the power module to receive the VDDIO voltage provided by the power module, an output terminal of the operational amplifier is electrically connected to a base of the triode, a collector of the NPN triode is used to input an excitation voltage with a preset amplitude, and an emitter of the NPN triode is electrically connected to an inverting input terminal of the operational amplifier.

Further, the power module includes a system main power module, a first DC-DC conversion module and a second DC-DC conversion module, the system main power module is configured to provide input voltages to the first DC-DC conversion module and the second DC-DC conversion module, the first DC-DC conversion module is configured to convert a voltage provided by the system main power module into the VDDIO voltage required by the device to be tested, the second DC-DC conversion module is configured to convert a voltage provided by the system main power module into other voltages required by the device to be tested, and the system main power module is further configured to provide an excitation voltage with a preset amplitude to the voltage follower circuit.

Further, the test equipment further comprises an output interface module, and the output interface module is used for providing the output voltages or signals of the first DC-DC conversion module, the second DC-DC conversion module and the signal level conversion circuit to the equipment to be tested.

Furthermore, a connection point exists between the input end of the voltage follower circuit, which receives the VDDIO voltage, and the output end of the power module, and the length of a wire between the connection point and the output interface is smaller than a preset length.

Further, the test equipment includes a plurality of sets of the voltage follower circuits and the signal level conversion circuits.

Further, the first DC-DC conversion module includes a current acquisition circuit.

Generally speaking, compared with the prior art, through the technical scheme of the invention, the hardware circuit of the test equipment is improved, on the premise of ensuring that the communication is established between the test equipment and the equipment to be tested through the IO channel, the VDDIO voltage is not consumed by the signal level conversion circuit, the influence on the measurement of the current, the energy consumption and the like of the equipment to be tested is very small and can be almost ignored, so that the measurement of the current, the energy consumption and the like of the equipment to be tested is more accurate, software algorithm correction is not needed, the product test cost is greatly reduced, the product test efficiency is improved, and the circuit structure is simple and easy to implement.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic circuit structure diagram of a testing apparatus according to an embodiment of the present disclosure;

fig. 2 is a schematic circuit diagram of a testing apparatus according to another embodiment of the present application;

fig. 3 is a schematic circuit diagram of a test apparatus including a circuit acquisition circuit according to another embodiment of the present application;

fig. 4 is a circuit diagram of a voltage follower circuit based on an N-channel MOS transistor according to another embodiment of the present application;

fig. 5 is a circuit diagram of an NPN transistor-based voltage follower circuit according to another embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

The terms "first," "second," "third," and the like in the description and claims of this application and in the above-described drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

As shown in fig. 1, a test apparatus according to an embodiment of the present invention includes: the voltage follower circuit comprises a power module, a voltage follower circuit and a signal level conversion circuit, wherein the input end of the voltage follower circuit is electrically connected with the output end of the power module so as to receive VDDIO voltage required by equipment to be tested, which is provided by the power module, the output end of the voltage follower circuit is electrically connected with the voltage input end of the signal level conversion circuit, and the output voltage of the voltage follower circuit changes along with the change of the input VDDIO voltage.

The voltage follower circuit is characterized in that the output voltage and the input VDDIO voltage can be almost considered to be equal along with the change of the VDDIO voltage, the deviation usually depends on the circuit structure of the voltage follower circuit, such as the offset voltage (offset) between the forward input pin and the reverse input pin of the selected operational amplifier chip (operational amplifier), and also depends on the parameters of the open loop amplification factor of the operational amplifier chip, the phase margin of a feedback loop, the input current of the forward input pin of the chip, and the like. Generally, the difference between the forward input voltage of the voltage follower and the output voltage of the voltage follower is not more than 5uV, and if the performance of the operational amplifier per se is better, the voltage error is about 1uV or less, which can be practically ignored. In addition, from the perspective of an analog circuit, the operational amplifier of the voltage follower is often used as an ideal operational amplifier, that is, when the circuit is in a stable state, the bias voltage =0 (short virtual), the forward input pin current =0 (broken virtual) open loop amplification factor is infinite, the phase margin is extremely large or the feedback speed is extremely fast, so the input voltage of the voltage follower circuit is almost equal to the output voltage. And the principle of extremely small current is basically below 1uA, and the current of VDDIO is hardly consumed, so that the problem that the level conversion circuit consumes the current of VDDIO can be fundamentally solved. The voltage follower circuit is equivalent to copy VDDIO voltage supplied to the equipment to be tested through the follower circuit and then supply the voltage to the signal level conversion circuit for power supply, so that a new power supply is supplied to the signal level conversion circuit, and the original VDDIO voltage supplied to the equipment to be tested is not consumed.

The voltage follower circuit can be implemented in any conventional manner as long as it satisfies the above-described functions.

The signal level conversion circuit can be realized by adopting any conventional signal level conversion chip.

In the signal level conversion circuit equipped in the past, the VDDIO voltage is generally directly connected to the level conversion circuit, and the standard 3.3V control signal of the FPGA or the MCU is directly converted into the control signal corresponding to the VDDIO voltage, so that the power consumption of the VDDIO power supply consumed by the level conversion circuit is calculated into the actual power consumption of the product to be tested, which causes the total power consumption of the VDDIO power supply of the product to be tested to be larger, and further reflects the actual value of the test current.

In the prior art, a solution for VDDIO test current which is larger is to adopt software calibration or perform auxiliary calibration by other calibration instruments to enable the power consumption of the measured current of the test equipment VDDIO to be close to 0, and the later calibration mode needs to perform complex algorithm optimization and possibly generates a nonlinear condition.

This application need not carry out software calibration, but directly improve through the hardware circuit to test equipment, under the prerequisite of establishing communication through the IO passageway between assurance test equipment and the equipment that awaits measuring, can also make signal level converting circuit not consume VDDIO voltage, treat the electric current of equipment that awaits measuring, the influence of measuring such as energy consumption is very little, can ignore almost, consequently make the electric current of treating equipment that awaits measuring, the measurement such as energy consumption is more accurate, and need not to carry out software algorithm and correct, greatly reduced product test cost, product test efficiency has been promoted, and circuit structure is simple to realize easily.

Furthermore, the test equipment also comprises a control module, and a control signal input end of the signal level conversion circuit is electrically connected with the control module. The control module can be an MCU, an FPGA and the like and is used for communication between the test equipment and the equipment to be tested. The device under test may be a module under test, etc. The control signal includes various types of signals transmitted through the IO channel.

Further, the signal level conversion circuit converts the standard level control signal input by the control module into a control signal of a level required by the device to be tested based on the output voltage of the voltage follower circuit, and then outputs the control signal to the device to be tested. The signal level conversion circuit performs level conversion on the control signal output by the control module, so that the IO power supply voltage of the test equipment is the same as that of the equipment to be tested, and the basic requirement of communication establishment of an IO channel is met between the test equipment and the equipment to be tested.

In one example, assuming that the IO voltage of the device to be tested is 1.8V and the IO voltage of the control module of the measurement device is 3.3V, the signal level conversion circuit of the measurement device converts the IO communication voltage of the control module of 3.3V into 1.8V.

As shown in fig. 2, further, the power supply module includes a system main power supply module, a first DC-DC conversion module, i.e., VDDIO power supply DC-DC circuit module in the figure, and a second DC-DC conversion module, i.e., other power supply DC-DC circuit modules in the figure. The system main power supply module is used for respectively providing input voltage for the first DC-DC conversion module and the second DC-DC conversion module. The first DC-DC conversion module is used to convert the voltage provided by the system main power module into VDDIO voltage required by the device under test, which may also be referred to as VDDIO power supply. The second DC-DC conversion module is used for converting the voltage provided by the system main power supply module into other voltages required by the equipment to be tested, and the system main power supply module is also used for providing excitation voltage with a preset amplitude value for the voltage follower circuit. The system main power supply module is also used for supplying power to the control module.

Further, the device comprises an output interface module, wherein the output interface module is used for providing the output voltages or signals of the first DC-DC conversion module, the second DC-DC conversion module and the signal level conversion circuit to the device to be tested.

Furthermore, there is a connection point between the input terminal of the voltage follower circuit receiving the VDDIO voltage and the output terminal of the power module, and the length of the wire between the connection point and the output interface is less than a preset length, for example, 1 cm. The preset length may specifically be determined according to an acceptable maximum error. Due to the line loss, the voltages between the output interface and the connection point between the input terminal of the voltage follower circuit receiving the VDDIO voltage and the output terminal of the power supply module are not completely equal, i.e., there is an error. And determining the maximum acceptable line loss between the connecting point and the output interface according to the acceptable maximum error, and calculating the maximum length of the lead between the connecting point and the output interface, namely the preset length, according to the maximum acceptable line loss, the resistance of the lead in unit length and the current flowing through the lead. The purpose of doing so is to make the VDDIO voltage of the input end of the access voltage follower circuit be close to the output interface of the test equipment as much as possible, thus can guarantee the output voltage of the follower module is equal to the VDDIO voltage of the output interface of the test equipment as much as possible, can guarantee the signal output level of the signal level switching circuit is equal to the VDDIO voltage of the output interface of the test equipment as much as possible at the same time.

Further, the test equipment includes a plurality of sets of voltage follower circuits and signal level conversion circuits. The purpose of the multiple groups of voltage follower circuits and signal level conversion circuits is to enable the test equipment to support multiple different devices to be tested, and one group of voltage follower circuits and signal level conversion circuits provides VDDIO voltage and control signals after level conversion for one device to be tested. If the VDDIO voltages required by several devices to be tested are the same, part or all of the voltage follower circuit and the signal level conversion circuit can be shared.

As shown in fig. 3, further, the first DC-DC conversion module and the second DC-DC conversion module further include a current collecting circuit. The current acquisition circuit can be used for testing the current of the device to be tested. The VDDIO power supply can be provided with a current acquisition circuit.

Two preferred implementations of the voltage follower circuit are described in detail below.

As shown in fig. 4, in one embodiment, the voltage follower circuit includes an operational amplifier and an N-channel MOS transistor, a non-inverting input terminal of the operational amplifier is electrically connected to the output terminal of the power supply module to receive the VDDIO voltage provided by the power supply module, an output terminal of the operational amplifier is electrically connected to a gate of the N-channel MOS transistor, a drain of the N-channel MOS transistor is used to input the excitation voltage with the predetermined amplitude, and a source of the N-channel MOS transistor is electrically connected to an inverting input terminal of the operational amplifier. The excitation voltage with the preset amplitude is larger than the VDDIO voltage of the non-inverting input end of the operational amplifier and smaller than the maximum gate voltage which can be borne by the MOS tube. Specifically, the excitation voltage at the input end of the MOS transistor is actually greater than the voltage of VDDIO by about 1V, so that the output voltage of the voltage follower circuit can reach VDDIO only when the MOS transistor has a certain voltage drop.

After the VDDIO voltage is connected to the operational amplifier, the characteristic that the voltages of the positive input end and the negative input end of the operational amplifier are almost equal in a stable working state is utilized to ensure that the power supply input of the voltage following module is equal to the VDDIO voltage connected to the input end of the operational amplifier. When the VDDIO voltage connected into the operational amplifier changes, the output voltage of the voltage following module changes along with the change of the VDDIO voltage. Because the input impedance of the operational amplifier chip is almost infinite, the current of the positive input end connected to the VDDIO voltage is extremely small and is usually less than 1uA, so the current acquisition of the VDDIO power supply is influenced a little, and the problems of power consumption of the level conversion chip and inaccurate acquisition of the output current of the VDDIO power supply can be fundamentally solved by adding the circuit in the measuring equipment.

In another embodiment, as shown in fig. 5, the N-channel MOS transistor in fig. 4 is replaced by an NPN transistor. The voltage following circuit comprises an operational amplifier and an NPN triode, wherein the non-inverting input end of the operational amplifier is electrically connected with the output end of the power supply module so as to receive VDDIO voltage provided by the power supply module, the output end of the operational amplifier is electrically connected with the base electrode of the triode, the collector electrode of the NPN triode is used for inputting excitation voltage with preset amplitude, and the emitter electrode of the NPN triode is electrically connected with the inverting input end of the operational amplifier.

In another embodiment, the operational amplifier in fig. 4 and 5 can be replaced by a differential circuit.

The above description is merely an exemplary embodiment of the present disclosure, and the scope of the present disclosure should not be limited thereby. That is, all equivalent changes and modifications made in accordance with the teachings of the present disclosure are intended to be included within the scope of the present disclosure. Embodiments of the present disclosure will be readily apparent to those skilled in the art from consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A test apparatus, comprising: the VDDIO voltage detection circuit comprises a power module, a voltage follower circuit, a signal level conversion circuit, a control module and an output interface module, wherein the input end of the voltage follower circuit is electrically connected with the output end of the power module to receive the VDDIO voltage required by equipment to be detected provided by the power module, the output end of the voltage follower circuit is electrically connected with the voltage input end of the signal level conversion circuit, the output voltage of the voltage follower circuit changes along with the change of the VDDIO voltage, the power module comprises a system main power module and a first DC-DC conversion module, the first DC-DC conversion module is used for converting the voltage provided by the system main power module into the VDDIO voltage required by the equipment to be detected,

the control signal input end of the signal level conversion circuit is electrically connected with the control module;

the signal level conversion circuit converts the standard level control signal input by the control module into a control signal of the level required by the equipment to be tested based on the output voltage of the voltage follower circuit and outputs the control signal to the equipment to be tested,

the output interface module is used for providing the output voltage or the signal of the first DC-DC conversion module and the signal level conversion circuit to a device to be tested.

2. The test apparatus of claim 1, wherein the voltage follower circuit comprises an operational amplifier and an N-channel MOS transistor, a non-inverting input of the operational amplifier is electrically connected to an output of the power supply module to receive the VDDIO voltage provided by the power supply module, an output of the operational amplifier is electrically connected to a gate of the N-channel MOS transistor, a drain of the N-channel MOS transistor is used for inputting the excitation voltage of the preset magnitude, and a source of the N-channel MOS transistor is electrically connected to an inverting input of the operational amplifier.

3. The test apparatus as claimed in claim 1, wherein the voltage follower circuit comprises an operational amplifier and an NPN transistor, a non-inverting input terminal of the operational amplifier is electrically connected to the output terminal of the power supply module to receive the VDDIO voltage provided by the power supply module, an output terminal of the operational amplifier is electrically connected to a base of the transistor, a collector of the NPN transistor is used to input the pumping voltage of the predetermined magnitude, and an emitter of the NPN transistor is electrically connected to an inverting input terminal of the operational amplifier.

4. The test device of claim 1, wherein the power module further comprises a second DC-DC conversion module, the system main power module is further configured to provide an input voltage to the second DC-DC conversion module, the second DC-DC conversion module is configured to convert the voltage provided by the system main power module into another voltage required by the device under test, and the system main power module is further configured to provide an excitation voltage with a preset amplitude to the voltage follower circuit.

5. The test device of claim 4, wherein the output interface module is further to provide the output voltage of the second DC-DC conversion module to a device under test.

6. The test device of claim 5, wherein a connection point exists between an input terminal of the voltage follower circuit receiving the VDDIO voltage and an output terminal of the power module, and a length of a wire between the connection point and the output interface is less than a preset length of 1 cm.

7. The test apparatus of claim 1, comprising a plurality of sets of the voltage follower circuits and the signal level shifter circuits.

8. The test apparatus of claim 5, wherein the first DC-DC conversion module includes a current acquisition circuit.