CN113933638A - Test equipment of fingerprint image module - Google Patents
Test equipment of fingerprint image module Download PDFInfo
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- CN113933638A CN113933638A CN202111281913.1A CN202111281913A CN113933638A CN 113933638 A CN113933638 A CN 113933638A CN 202111281913 A CN202111281913 A CN 202111281913A CN 113933638 A CN113933638 A CN 113933638A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/52—Testing for short-circuits, leakage current or ground faults
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/54—Testing for continuity
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F13/38—Information transfer, e.g. on bus
- G06F13/42—Bus transfer protocol, e.g. handshake; Synchronisation
- G06F13/4282—Bus transfer protocol, e.g. handshake; Synchronisation on a serial bus, e.g. I2C bus, SPI bus
Abstract
The invention discloses a testing device of a fingerprint image module, which comprises: the sensor interface is in communication connection with the switch circuit module and is used for connecting the fingerprint image module to be tested; the switching circuit module is respectively in communication connection with the DC function testing module and the image function testing module; the main controller module is in communication connection with the DC function testing module, the image function testing module and the switch circuit module respectively; the USB communication module is in communication connection with the main controller module and is used for connecting an external computer; and the power supply module is electrically connected with the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module respectively and can supply power for the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module. The testing equipment can conveniently and efficiently test the DC function and the image function of the fingerprint image module to obtain an accurate test result.
Description
Technical Field
The invention relates to the field of test equipment, in particular to test equipment for a fingerprint image module.
Background
The application of fingerprint module is more and more general, all is provided with the fingerprint module in common cell-phone, computer, intelligent wrist-watch and the intelligent lock in the life. Need test before leaving the factory after the fingerprint module production, conventional image module Interface is MIPI or DVP, and fingerprint module Interface is SPI (Serial Peripheral Interface, namely Serial Peripheral Interface) Interface, consequently conventional image module test equipment is not applicable to the test of fingerprint image module, the test equipment that can general test fingerprint image module does not exist in the existing market, most producer test fingerprint image module all utilizes the test equipment of customization, there is the poor problem of commonality, and, the test equipment of current image module is mostly Serial test, still there is the problem of test efficiency low.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
The invention aims to provide test equipment for a fingerprint image module, which can efficiently and accurately carry out DC (direct current) function test and image function test on the fingerprint image module, and further solve the technical problems in the prior art.
The purpose of the invention is realized by the following technical scheme:
the embodiment of the invention provides a test device of a fingerprint image module, which comprises:
the device comprises a sensor interface, a switch circuit module, a DC function test module, an image function test module, a main controller module, a USB communication module and a power supply module; wherein the content of the first and second substances,
the sensor interface is in communication connection with the switch circuit module and is used for connecting a fingerprint image module to be tested;
the switching circuit module is respectively in communication connection with the DC function testing module and the image function testing module;
the main controller module is in communication connection with the DC function testing module, the image function testing module and the switch circuit module respectively;
the USB communication module is in communication connection with the main controller module and is used for connecting an external computer;
the power module is electrically connected with the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module respectively and can supply power for the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module.
Compared with the prior art, the test equipment for the fingerprint image module provided by the invention has the beneficial effects that:
through setting up DC function test module and image function test module to with DC function test module and image function test module through switch circuit module and sensor interface connection, can carry out DC function test and image function test respectively to fingerprint image module with the switch switching mode, cooperate the main control unit module through the computer that USB communication module connects, convenient, the efficient reachs accurate test result.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.
Fig. 1 is a block diagram of an overall structure of a test apparatus according to an embodiment of the present invention;
FIG. 2 is a circuit diagram of a power module of a testing apparatus according to an embodiment of the present invention;
FIG. 3 is a circuit diagram of a USB3320 power supply circuit of a testing apparatus according to an embodiment of the present invention;
FIG. 4 is a circuit diagram of a signal PIN switch of the testing device according to the embodiment of the present invention;
FIG. 5 is a circuit diagram of an open short circuit current source of the test equipment according to an embodiment of the present invention;
FIG. 6 is a circuit diagram of a power supply operating current test of the test equipment according to an embodiment of the present invention;
FIG. 7 is a circuit diagram of a USB communication module of a testing apparatus according to an embodiment of the present invention;
fig. 8 is a schematic test flow diagram of the test equipment according to the embodiment of the present invention.
Detailed Description
The technical scheme in the embodiment of the invention is clearly and completely described below by combining the specific content of the invention; it is to be understood that the described embodiments are merely exemplary of the invention, and are not intended to limit the invention to the particular forms disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.
The terms that may be used herein are first described as follows:
the term "and/or" means that either or both can be achieved, for example, X and/or Y means that both cases include "X" or "Y" as well as three cases including "X and Y".
The terms "comprising," "including," "containing," "having," or other similar terms of meaning should be construed as non-exclusive inclusions. For example: including a feature (e.g., material, component, ingredient, carrier, formulation, material, dimension, part, component, mechanism, device, process, procedure, method, reaction condition, processing condition, parameter, algorithm, signal, data, product, or article of manufacture), is to be construed as including not only the particular feature explicitly listed but also other features not explicitly listed as such which are known in the art.
The term "consisting of … …" is meant to exclude any technical feature elements not explicitly listed. If used in a claim, the term shall render the claim closed except for the inclusion of the technical features that are expressly listed except for the conventional impurities associated therewith. If the term occurs in only one clause of the claims, it is defined only to the elements explicitly recited in that clause, and elements recited in other clauses are not excluded from the overall claims.
Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "secured," etc., are to be construed broadly, as for example: can be fixedly connected, can also be detachably connected or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms herein can be understood by those of ordinary skill in the art as appropriate.
The terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like are used in an orientation or positional relationship that is indicated based on the orientation or positional relationship shown in the drawings for ease of description and simplicity of description only, and are not intended to imply or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting herein.
The following describes the testing equipment of the fingerprint image module provided by the invention in detail. Details which are not described in detail in the embodiments of the invention belong to the prior art which is known to the person skilled in the art. Those not specifically mentioned in the examples of the present invention were carried out according to the conventional conditions in the art or conditions suggested by the manufacturer. The reagents or instruments used in the examples of the present invention are not specified by manufacturers, and are all conventional products available by commercial purchase.
As shown in fig. 1, an embodiment of the present invention provides a testing apparatus for a fingerprint image module, including:
the device comprises a sensor interface, a switch circuit module, a DC function test module, an image function test module, a main controller module, a USB communication module and a power supply module; wherein the content of the first and second substances,
the sensor interface is in communication connection with the switch circuit module and is used for connecting a fingerprint image module to be tested;
the switching circuit module is respectively in communication connection with the DC function testing module and the image function testing module;
the main controller module is in communication connection with the DC function testing module, the image function testing module and the switch circuit module respectively;
the USB communication module is in communication connection with the main controller module and is used for connecting an external computer;
the power module is electrically connected with the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module respectively and can supply power for the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module.
Preferably, the sensor interface is an SPI interface.
In the above test apparatus, the image function test module includes:
the device comprises an image acquisition circuit, a light source controller, a light source and a light source collector; wherein the content of the first and second substances,
the image acquisition circuit is connected between the switch circuit module and the main controller module;
the main controller module is in communication connection with the light source through the light source controller;
the light source is in communication connection with the main controller module through the light source collector.
In the test equipment, the image acquisition circuit adopts a one-way voltage level converter chip which can configure the level of a port and has inconsistent MOSI and MISO directions of communication pins;
the light source collector adopts a light source collecting circuit which is composed of a photoelectric conversion diode, a current amplifier and an analog-to-digital converter. Preferably, the unidirectional voltage level translator chip used employs an SN74AUP1T34 chip.
In the above test apparatus, the DC function test module includes:
the open-short circuit test circuit is formed by connecting a current source chip and an operational amplifier circuit and can output a current of plus or minus 100 uA;
and a current sampling module circuit which is composed of a high-side and low-side bidirectional current monitor chip (such as an INA226AIDGSR chip) with an I2C communication interface and can test quiescent current, working current, current of a configuration power supply terminal and monitor power. Preferably, the INA226AIDGSR chip is a product of TI corporation.
In the test equipment, the switch circuit module adopts a switch circuit formed by four-channel single-pole single-throw switch chips. Preferably, the four-channel single-pole single-throw switch chip is an ADG611YRUZ four-channel single-pole single-throw switch chip of AD company.
In the test equipment, the power supply module adopts a voltage stabilizer circuit which is composed of a power supply circuit chip and can output 3 paths of adjustable voltage. Preferably, the power circuit chip is a TPS7A7001 chip of TI company.
In the test equipment, the USB communication module adopts a USB communication circuit formed by a USB3320C chip.
In summary, the test equipment of the embodiment of the invention is provided with the DC function test module and the image function test module which are connected through the switch circuit module, and can respectively test the DC function and the image function of the fingerprint image module in a switch switching manner by matching with the main controller module, so as to obtain accurate results of the DC function test (including an open short circuit test, a static working current test and a working current test) and the image function test, and has the advantages of convenience in test and high test efficiency.
In order to more clearly show the technical solutions and the technical effects provided by the present invention, the following describes in detail a testing apparatus of a fingerprint image module provided by an embodiment of the present invention with specific embodiments.
Examples
The testing equipment is mainly used for DC functional testing and image functional testing of the fingerprint image module, wherein the DC functional testing comprises open-short circuit testing, static working current testing and working current testing; the test apparatus is constituted as shown in fig. 1, and includes: the device comprises a sensor interface, a switch circuit module, a DC function test module, an image function test module, a main controller module, a USB communication module and a power supply module;
the sensor interface is respectively connected with the DC function testing module and the image function testing module through the switch circuit module;
the DC function testing module and the image function testing module are both connected with the main controller module;
the main control module is connected with the USB communication module and is connected with an external computer through the USB communication module;
the power supply module is electrically connected with the switch circuit module, the DC function testing module, the main controller module and the USB communication module respectively and supplies power to the switch circuit module, the DC function testing module, the main controller module and the USB communication module.
In the above test equipment, the circuit of the power module is specifically configured as shown in fig. 2, and is a voltage regulator circuit formed by a power chip, the type of the power chip used by the power module is a TPS7a7001 chip of TI corporation, the chip is a high-performance, positive voltage, Low Drop Out (LDO) voltage regulator, and the output voltage can be set by using an external voltage divider, so as to achieve the purpose of regulating the voltage output.
In the test equipment, the USB communication module adopts a USB communication circuit consisting of a USB3320C chip, and the specific circuit constitution is as shown in FIG. 3, the USB3320C chip needs 3.3V and 1.8V external power supply, so that LD3985M18R power supply chips of ST company are adopted for power supply. The USB3320C chip is an ultra-low noise linear regulator.
In the above test equipment, the switch module circuit may specifically adopt a single signal switch circuit as shown in fig. 4, and the switching of the DC function test and the image function test performed by the test equipment on the tested fingerprint image module can be realized by the single signal switch circuit, preferably, the switch circuit type selection chip is a four-channel single-pole single-throw switch ADG611YRUZ chip of AD company.
In the above test apparatus, the DC function test module adopts a DC function test circuit, including: an open-short circuit test circuit and a current measurement circuit; the open-short circuit test circuit is characterized in that a circuit of the open-short circuit test circuit is shown in fig. 5, the circuit provides a FIMV mode according to an IC open-short circuit test principle, a REF200AU of a current source chip model TI company is selected, and a circuit for outputting a positive current and a negative current of 100uA is constructed through an operational amplifier;
the circuit structure of the current measuring circuit is as shown in fig. 6, the function of testing quiescent current and working current can be realized, a current and power monitor is configured at a power supply end, a specific sampling chip is an INA226AIDGSR chip of TI company, the chip has a high-side and low-side measuring, bidirectional current and power monitor, and an I2C communication interface, and the chip can directly read the current value (in amperes), and has the characteristic of high efficiency.
In the above test equipment, the specific circuit of the USB communication module is shown in fig. 7, a USB3320 chip is used to form the USB communication circuit, the input end is 8bit data, the chip is provided with a 24M clock input, the output end is provided with an ESD protection chip ECMF02, the output end interface is a relatively firm USB-B port, and the USB communication module can be used in cooperation with a chip of a main controller module supporting USB full-speed/high-speed transmission.
In the above test apparatus, the image function test module includes: the device comprises an image acquisition circuit, a light source controller, a light source and a light source collector; wherein the content of the first and second substances,
the image acquisition circuit can realize that the port level can be configured the function to and main communication pin MOSI and MISO direction are inconsistent, can satisfy the fingerprint image module that adopts the testing of SPI interface like this, the inconsistent problem of different module configuration port levels specifically chooses for use one-way voltage level converter, mainly considers the communication direction, and the specific type selection of chip is SN74AUP1T 34.
The light source controller adopts a communication mode as a serial port.
The light source collector uses a photoelectric conversion diode of Hamamatsu photon company, the specific model is SI0625, a high-precision current amplifier is used for voltage conversion, and a 16-bit low-power consumption ADC is used for sampling.
In the above test equipment, system software including two parts can be used, one part is control firmware for controlling the main controller module, and mainly completes logic control of the bottom layer functional module, and the other part is application at the computer end and algorithm test at the integrated image end. The specific test flow is shown in fig. 8, and includes the following steps: the method comprises the steps of equipment identification, initialization configuration, light source controller reset, OS test, static current test, working current test, image function test, test result display, test data generation, test completion and the like. It is to be noted that any control software or the like capable of realizing the above-mentioned function control, test control, result output and data recording can be used as the system software of the above-mentioned test apparatus.
In summary, the test equipment of the embodiment of the invention has at least the following advantages: the fingerprint image module can be conveniently and efficiently tested, and an accurate test result is obtained.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims. The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
Claims (10)
1. The utility model provides a test equipment of fingerprint image module which characterized in that includes:
the device comprises a sensor interface, a switch circuit module, a DC function test module, an image function test module, a main controller module, a USB communication module and a power supply module; wherein the content of the first and second substances,
the sensor interface is in communication connection with the switch circuit module and is used for connecting a fingerprint image module to be tested;
the switching circuit module is respectively in communication connection with the DC function testing module and the image function testing module;
the main controller module is in communication connection with the DC function testing module, the image function testing module and the switch circuit module respectively;
the USB communication module is in communication connection with the main controller module and is used for connecting an external computer;
the power module is electrically connected with the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module respectively and can supply power for the sensor interface, the switch circuit module, the DC function testing module, the main controller module and the USB communication module.
2. The apparatus for testing the fingerprint image module of claim 1, wherein the image function testing module comprises:
the device comprises an image acquisition circuit, a light source controller, a light source and a light source collector; wherein the content of the first and second substances,
the image acquisition circuit is connected between the switch circuit module and the main controller module;
the main controller module is in communication connection with the light source through the light source controller;
the light source is in communication connection with the main controller module through the light source collector.
3. The apparatus for testing fingerprint image module of claim 2, wherein said image acquisition circuit employs a unidirectional voltage level translator chip capable of configuring port levels and having non-uniform orientation of communication pins MOSI and MISO;
the light source collector adopts a light source collecting circuit which is composed of a photoelectric conversion diode, a current amplifier and an analog-to-digital converter.
4. The apparatus for testing fingerprint image module of claim 3 wherein said one-way voltage level converter chip is SN74AUP1T34 chip.
5. The testing apparatus of the fingerprint image module of any one of claims 1 to 4, wherein the DC function testing module comprises:
the open-short circuit test circuit is formed by connecting a current source chip and an operational amplifier circuit and can output a current of plus or minus 100 uA;
and a current sampling module circuit which is composed of a high-side and a low-side bidirectional current monitor chip with an I2C communication interface and can test quiescent current, working current, current of a configuration power supply terminal and monitor power.
6. The apparatus for testing the fingerprint image module of any one of claims 1 to 4, wherein the switch circuit module employs a switch circuit formed by a four-channel single-pole single-throw switch chip.
7. The apparatus for testing fingerprint image module of claim 6 wherein said four-channel single-pole single-throw switch chip is ADG611YRUZ four-channel single-pole single-throw switch chip from AD.
8. The fingerprint image module testing device of any one of claims 1 to 4, wherein the power supply module adopts a voltage regulator circuit which is composed of a power supply circuit chip and can output 3 adjustable voltages.
9. The apparatus for testing fingerprint image module of claim 8, wherein the power circuit chip is TPS7A7001 chip of TI company.
10. The fingerprint image module testing device of any one of claims 1 to 4, wherein the USB communication module adopts a USB communication circuit formed by a USB3320C chip.
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| CN202111281913.1A CN113933638A (en) | 2021-11-01 | 2021-11-01 | Test equipment of fingerprint image module |
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| CN202111281913.1A CN113933638A (en) | 2021-11-01 | 2021-11-01 | Test equipment of fingerprint image module |
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| CN111175637A (en) * | 2020-01-09 | 2020-05-19 | 深圳市正宇兴电子有限公司 | Optical SOC chip testing method and system based on function test |
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| CN201600404U (en) * | 2009-11-18 | 2010-10-06 | 深圳市度信科技有限公司 | Multifunctional camera test plate |
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