Micro controller embedded voltage reference and temperature sensor testing device

Abstract

According to the testing device for the embedded voltage reference and temperature sensor of the microcontroller, a PC is used for sending a control word to a lower computer through a UART port, the lower computer receives the control word and then collects the voltage reference of the microcontroller of a set station through a digital multimeter, the temperature sensor is started to conduct temperature collection, and the temperature sensor is started to conduct temperature measurement. A voltage reference collected by the digital multimeter is uploaded to the PC through the USB port, a temperature sampling value is uploaded to the PC through the UART port by the lower computer and is distinguished, printed and stored on the PC, and automatic testing of the embedded voltage reference and the temperature sensor of the microcontroller is achieved. While automation is realized, the test device and method also consider the mass production condition, and the lower computer controls the microcontroller to realize erasing and programming of a self-test program; the simultaneous measurement number of the microcontroller is increased through variable address and multi-station hardware design; and through independent design of the lower computer and the microcontroller, the requirements of the embedded voltage reference of the microcontroller and the full-temperature-zone online test of the temperature sensor are met.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit testing, and in particular to a full-temperature-range online testing device for a microcontroller embedded voltage reference and a temperature sensor. Background Art

[0002] A microcontroller is an integrated circuit used to control other parts of an electronic system. It integrates a microprocessor unit, memory, peripherals, etc. Voltage reference and temperature sensor are important peripherals of the microcontroller. The change of their characteristics with temperature is an important factor affecting the working condition of the electronic system. It is necessary to conduct full-temperature zone testing to evaluate their temperature characteristics. At present, a heat flow hood is used to ensure the temperature conditions, and a digital multimeter is used for embedded voltage reference. The sampling value of the temperature sensor is directly output to the microcontroller port. The temperature control time for each temperature point is at least 5 minutes, and only one circuit can be measured for power at a time. After entering the batch production stage, a device is needed to conduct online testing of the embedded voltage reference and temperature sensor in the full temperature zone under set temperature conditions. Summary of the invention

[0003] Based on the characteristics of requiring a stable temperature environment and high test efficiency when conducting batch online testing of microcontroller embedded voltage reference and temperature sensor over the full temperature range, a microcontroller embedded voltage reference and temperature sensor testing device is provided to complete the online evaluation of the microcontroller embedded voltage reference and temperature sensor over the full temperature range.

[0004] The present invention adopts the following technical scheme: a microcontroller embedded voltage reference and temperature sensor testing device, comprising a PC, a lower computer, a multi-way selection unit, a test board connected in sequence, and a digital multimeter connected to the multi-way selection unit and the PC;

[0005] The PC is used to send a control word to the lower computer, read the test result of the reference voltage from the digital multimeter, and distinguish, store and display the reference voltage obtained from the digital multimeter and the temperature value obtained from the lower computer;

[0006] The lower computer is used to receive the PC control word, control the multi-channel selection unit to select the test board station, write, verify and erase the microcontroller self-test program, and collect and transmit the test results of the temperature value;

[0007] The multi-channel selection unit is used to control the connection between the lower computer port and each microcontroller station on the test board, and to control the connection between the digital multimeter and each microcontroller station on the test board;

[0008] The test board is used to establish a hardware environment for a multi-station microcontroller and independently works in the full temperature range required by the temperature performance of the microcontroller.

[0009] The lower computer includes a microprocessor, a USB to serial port chip, and an indicator light; the microprocessor is connected to the test board through a UART interface and is connected to the PC through a USB to serial port chip; the indicator light is used to display the current working status of the microcontroller;

[0010] The microprocessor is used to receive the control word sent by the PC, identify the control instruction, control the multi-way selection unit, and set the station microcontroller to execute the preset function;

[0011] The USB to serial port chip is used for transmission of control words and temperature test results between the microprocessor and the PC.

[0012] The indicator light is used to display the working status of the microprocessor erasing, programming and collecting.

[0013] The multi-channel selection unit includes two 16-channel analog switches, the first 16-channel analog switch is used to switch the reference voltage of the output setting station microcontroller to the digital multimeter, and the second 16-channel analog switch is used to switch the output of the lower computer microprocessor to the microcontroller of the setting station for erasing and programming operations;

[0014] The first 16-way analog switch has independent channels connected to the reference voltage outputs of the microcontrollers of the test board, a common terminal connected to the positive voltage input terminal of the digital multimeter, and a control terminal and an enable terminal connected to the IO port of the microprocessor;

[0015] The second 16-way analog switch has independent channels connected to the programming port data terminals of each microcontroller of the test board, and the common terminal, control terminal and enable terminal are connected to the IO port of the microprocessor of the lower computer.

[0016] The test board includes 16 stations of microcontrollers, each station has a reserved test socket for placing and replacing the microcontroller to be tested, and the pins of the test socket correspond one to one with the pins of the microcontroller to be tested;

[0017] Each station microcontroller has a C2 protocol communication interface, which is used as a programming port data terminal and connected to the IO port of the lower computer microprocessor through the second 16-way analog switch for erasing and programming;

[0018] Each station microcontroller is connected to the lower computer microprocessor through a UART interface to transmit the temperature test result; each station microcontroller reserves a resistor at the same pin position for setting the station.

[0019] Use the two USB interfaces of the PC, the two UART interfaces of the lower microprocessor, and the UART interface of the microcontroller at each station of the test board;

[0020] The first USB interface of the PC is connected to the first UART interface of the microprocessor of the lower computer through a USB-to-serial port chip for sending control words;

[0021] The second USB interface of the PC is connected to the digital multimeter and is used to save the reference voltage measurement result;

[0022] The second UART interface of the lower computer microprocessor is connected to the UART interface of each station microcontroller.

[0023] The lower computer and the multi-channel selection unit, as well as the multi-channel selection unit and the test board are connected by wires. The multi-channel selection unit and the test board are placed in a temperature environment of -55℃ to 125℃, and the PC and the lower computer work in a normal temperature environment.

[0024] The test method of the microcontroller embedded voltage reference and temperature sensor test device is to erase and program the microcontroller, including the following steps:

[0025] 1) The PC sends an erase instruction of a set station on the test board to the lower computer through the first USB interface;

[0026] 2) The lower computer performs instruction parsing and connects the common terminal to the programming port data terminal of the microcontroller of the setting station through the enable terminal and the control terminal of the second 16-way analog switch;

[0027] 3) The microprocessor of the lower computer erases the microcontroller of the setting station according to the C2 protocol;

[0028] 4) The microprocessor of the lower computer programs the setting station microcontroller according to the C2 protocol and downloads the self-test program into the Flash of the setting station microcontroller;

[0029] 5) Return to step 1) until all 16-bit microcontrollers have completed erasing and programming.

[0030] The self-test program is a program executed by the microcontroller on the test board after it is powered on, including starting the voltage reference and outputting it, reading the station setting status, receiving the control word sent by the lower computer to match the setting station, starting the embedded temperature sensor and uploading the temperature sampling value to the lower computer;

[0031] Each station microcontroller reserves a resistor at the same pin position, and the station is set by software through a self-test program to achieve a unified self-test program code for each station.

[0032] Performing a voltage benchmark test on a set station includes the following steps:

[0033] (1) The PC sends a voltage reference test instruction for a set station on the test board to the lower computer through the first USB interface;

[0034] (2) The lower computer performs instruction parsing, and connects the common terminal to the voltage reference output terminal of the setting station microcontroller through the enable terminal and the control terminal of the first 16-way analog switch, so that the voltage reference output terminal of the setting station is connected to the digital multimeter.

[0035] (3) The PC reads the measurement value of the digital multimeter through the second USB interface, and performs identification, storage and display;

[0036] (4) Return to step (2) until all 16-position microcontrollers have completed the voltage benchmark test.

[0037] Performing a temperature sensor test on a set station includes the following steps:

[0038] ① The PC sends a voltage reference test instruction for a set station on the test board to the lower computer through the first USB interface;

[0039] ② The lower computer parses the instruction and matches the setting station. After the matching is successful, the microcontroller of the setting station starts the temperature sensor and sends the temperature sampling value to the microprocessor of the lower computer through the second UART interface, and then uploads it to the PC through the USB to serial port chip;

[0040] ③The PC determines, stores and displays the temperature sampling values.

[0041] ④ Return to step ① until all 16-bit microcontrollers have completed the voltage benchmark test.

[0042] The present invention has the following beneficial effects and advantages:

[0043] 1. The present invention can realize batch online testing of microcontroller embedded voltage reference and temperature sensor in the whole temperature range, thereby improving the testing efficiency while ensuring the temperature environment.

[0044] 2. The present invention adopts a three-level control method of a PC, a slave computer, and a test board to achieve erasing, programming, voltage reference, and sampling of a temperature sensor of a microcontroller to be tested. The test board, the PC, and the slave computer can operate under different temperature conditions and can be widely used in electrical testing of integrated circuits at specific temperatures.

[0045] 3. The present invention uses hardware to set the microcontroller station to be tested, and through software identification, it can ensure that the self-test program code of each station is unified, thereby improving the convenience of operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 Schematic diagram of the test device for the voltage reference and temperature sensor embedded in the microcontroller;

[0047] Figure 2Flowchart for online testing of the microcontroller's embedded voltage reference and temperature sensor over the entire temperature range. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0049] A microcontroller embedded voltage reference and temperature sensor testing device is provided, comprising:

[0050] PC, microprocessor, 16-way analog switch, test socket, DC regulated power supply, digital multimeter and other parts. The PC is used as the general control part to control the test process, identify and store the test results; the microprocessor is responsible for communicating with the PC, selecting the station of the microcontroller under test, controlling the 16-way analog switch to erase, program, switch the voltage reference of the microcontroller under test, and identify and store the sampling values ​​of the voltage reference and temperature sensor; the DC regulated power supply provides stable power supply for the microcontroller and the entire test device, and the digital multimeter is used to sample the voltage reference. The lower computer is connected to the multi-way selection unit and the test board through high-temperature wires. The multi-way selection unit and the test board are placed in a temperature environment of -55℃ to 125℃, and the PC and the lower computer work in a normal temperature environment. Among them, the high-temperature wire adopts a silver-plated wire that can withstand -80℃ to 250℃.

[0051] Preferably, a USB interface of the PC is connected to a UART interface of the microprocessor via a USB-to-serial port chip for sending control words; a USB interface of the PC is connected to a digital multimeter for storing reference voltage measurement results.

[0052] As a preferred embodiment, the microprocessor is a 32-bit MCU with an online debugging function and a 2-way UART peripheral module for debugging and controlling the test device. The 1-way UART interface of the microprocessor is connected to the USB interface of the PC through a USB-to-serial port chip, and the 1-way UART interface is connected to the UART interface of each station microcontroller.

[0053] Preferably, the 16-way analog switch is model ADG1606. Two 16-way analog switches are used to output the reference voltage of the microcontroller of the setting station to the digital multimeter, and perform erasing and programming operations on the microcontroller of the setting station; the independent channels of the first 16-way analog switch are respectively connected to the reference voltage output of each microcontroller of the test board, the common end is connected to the positive voltage input end of the digital multimeter, and the control end and the enable end are connected to the IO port of the microprocessor. The independent channels of the second 16-way analog switch are respectively connected to the data end of the programming port of each microcontroller of the test board, and the common end, the control end and the enable end are connected to the IO port of the microprocessor. Among them, the control end is an independent end that controls 16 channels. When a certain control end is connected to the common end, the path corresponding to the control end is connected; the enable end is used to control whether the current analog switch is working.

[0054] Preferably, the selected test socket can repeatedly load the microcontroller under test, and the temperature range of the test socket is -55℃~125℃, which meets the requirements of full temperature zone testing. The lead-out terminals of the test socket correspond one-to-one with the lead-out terminals of the microcontroller under test. There are 16 test sockets on the test board, corresponding to 16 workstations. The 4 IO terminals at the same pin position of each microcontroller under test are connected to pull-up or pull-down resistors for setting the workstation, the UART ports are connected in parallel to the UART ports of the microprocessor, the voltage reference distribution is connected to the independent channels of the first 16-way analog switch, and the programming port data terminals are respectively connected to the independent channels of the second 16-way analog switch.

[0055] Specifically, the PC, as the overall control component of the entire test device, writes control codes for the digital multimeter and microprocessor based on the VC environment, selects the microprocessor to execute the test content by sending control words, and evaluates and stores the test results.

[0056] like Figure 1 , Figure 2 As shown, the present invention includes a PC, a microprocessor (STM32F103VCT6), a 16-way analog switch (ADG1606), a current-regulated power supply (N6705B), a digital multimeter (Keysight 34470) and the like.

[0057] The microcontroller under test is C8051F500, which is an embedded microcontroller with an internal voltage reference and temperature sensor. The voltage reference output value is 2.5V, the temperature drift coefficient is 33ppm / ℃, the temperature sensor has an operating range of -55℃ to 125℃, and the temperature slope is 3.33mV / ℃. All of them are temperature sensitive components.

[0058] Before testing, run the VC code on the PC, place the sample, wear an anti-static wristband, power on the control DC power supply, observe whether the indicator light of the lower computer is on, and make preparations before testing.

[0059] Erasing the microcontroller: Under normal temperature conditions, the PC sends an erase command for the setting position on the test board to the lower computer via USB; the lower computer interprets the command and connects the common end to the programming port data end of the setting position microcontroller through the enable end and control end of the second 16-way analog switch. The microprocessor of the lower computer erases the setting position microcontroller according to the C2 protocol.

[0060] Programming the microcontroller: Under normal temperature conditions, the PC sends the programming instructions for the setting position on the test board to the lower computer via USB; the lower computer parses the instructions and connects the common end to the programming port data end of the setting position microcontroller through the enable end and control end of the second 16-way analog switch. The microprocessor of the lower computer programs the setting position microcontroller according to the C2 protocol and downloads the self-test program to the Flash of the setting position microcontroller. Repeat the above steps until all 16-position microcontrollers are erased.

[0061] The self-test program is a program executed after the microcontroller on the test board is powered on, including starting the voltage reference and outputting it, reading the station setting status, receiving the control word sent by the lower computer to match the setting station, starting the embedded temperature sensor and uploading the temperature sampling value to the lower computer. Each station microcontroller reserves a resistor at the same pin position, and the station is set to 0000B~1111B by hardware. The station is set by reading the port status through the self-test program, which can realize the unification of the self-test program code for each station.

[0062] Voltage reference test: The PC sends the voltage reference test command of the set station on the test board to the lower computer via USB; the lower computer parses the command and connects the common end to the voltage reference output of the microcontroller of the set station through the enable end and control end of the first 16-way analog switch, that is, the voltage reference output of the set station is connected to the digital multimeter. The PC reads the measurement value of the digital multimeter through the USB port, and distinguishes, stores and displays it. Repeat the above steps until all 16-station microcontrollers have completed the voltage reference test. When executing the above steps, the multi-way selection unit and the test board are placed in a temperature environment of -55℃ to 125℃, and the PC and the lower computer work in a normal temperature environment.

[0063] The temperature sensor test includes the following steps: the PC sends the voltage reference test instruction of the set station on the test board to the lower computer through USB; the lower computer parses the instruction and matches the set station. After the match is successful, the microcontroller of the set station starts the temperature sensor and sends the temperature sampling value to the microprocessor of the lower computer through the UART interface, and then uploads it to the PC through the USB to serial port chip. The PC determines, stores and displays the temperature sampling value. Repeat the above steps until all 16-station microcontrollers have completed the voltage reference test. When executing the above steps, the multi-way selection unit and the test board are placed in a temperature environment of -55℃ to 125℃, and the PC and the lower computer work in a normal temperature environment.

Claims

1. A microcontroller embedded voltage reference and temperature sensor test device, characterized in that: It includes a PC, a lower computer, a multi-channel selection unit, a test board connected in sequence, and a digital multimeter connected to the multi-channel selection unit and the PC; The PC is used to send a control word to the lower computer, read the test result of the reference voltage from the digital multimeter, and distinguish, store and display the reference voltage obtained from the digital multimeter and the temperature value obtained from the lower computer; The lower computer is used to receive the PC control word, control the multi-channel selection unit to select the test board station, write, verify and erase the microcontroller self-test program, and collect and transmit the test results of the temperature value; The multi-channel selection unit is used to control the connection between the lower computer port and each microcontroller station on the test board, and to control the connection between the digital multimeter and each microcontroller station on the test board; The test board is used to establish a hardware environment for a multi-station microcontroller and independently works in the full temperature range required by the temperature performance of the microcontroller.

2. The microcontroller embedded voltage reference and temperature sensor testing device according to claim 1, characterized in that: The lower computer includes a microprocessor, a USB to serial port chip, and an indicator light; the microprocessor is connected to the test board through a UART interface and is connected to the PC through a USB to serial port chip; the indicator light is used to display the current working status of the microcontroller; The microprocessor is used to receive the control word sent by the PC, identify the control instruction, control the multi-way selection unit, and set the station microcontroller to execute the preset function; The USB to serial port chip is used for transmission of control words and temperature test results between the microprocessor and the PC. The indicator light is used to display the working status of the microprocessor erasing, programming and collecting.

3. A microcontroller embedded voltage reference and temperature sensor testing device according to claim 1, characterized in that: The multi-channel selection unit includes two 16-channel analog switches, the first 16-channel analog switch is used to switch the reference voltage of the output setting station microcontroller to the digital multimeter, and the second 16-channel analog switch is used to switch the output of the lower computer microprocessor to the microcontroller of the setting station for erasing and programming operations; The first 16-way analog switch has independent channels connected to the reference voltage outputs of the microcontrollers of the test board, a common terminal connected to the positive voltage input terminal of the digital multimeter, and a control terminal and an enable terminal connected to the IO port of the microprocessor; The second 16-way analog switch has independent channels connected to the programming port data terminals of each microcontroller of the test board, and the common terminal, control terminal and enable terminal are connected to the IO port of the microprocessor of the lower computer.

4. The microcontroller embedded voltage reference and temperature sensor testing device according to claim 1, characterized in that: The test board includes 16 stations of microcontrollers, each station has a reserved test socket for placing and replacing the microcontroller to be tested, and the pins of the test socket correspond one to one with the pins of the microcontroller to be tested; Each station microcontroller has a C2 protocol communication interface, which is used as a programming port data terminal and connected to the IO port of the lower computer microprocessor through the second 16-way analog switch for erasing and programming; Each station microcontroller is connected to the lower computer microprocessor through a UART interface to transmit the temperature test result; each station microcontroller reserves a resistor at the same pin position for setting the station.

5. The microcontroller embedded voltage reference and temperature sensor testing device according to claim 1, characterized in that: Use the two USB interfaces of the PC, the two UART interfaces of the lower microprocessor, and the UART interface of the microcontroller at each station of the test board; The first USB interface of the PC is connected to the first UART interface of the microprocessor of the lower computer through a USB-to-serial port chip for sending control words; The second USB interface of the PC is connected to the digital multimeter to store the reference voltage measurement result; the second UART interface of the lower computer microprocessor is connected to the UART interface of each station microcontroller.

6. The microcontroller embedded voltage reference and temperature sensor testing device according to claim 1, characterized in that: The lower computer and the multi-channel selection unit, as well as the multi-channel selection unit and the test board are connected by wires. The multi-channel selection unit and the test board are placed in a temperature environment of -55℃ to 125℃, and the PC and the lower computer work in a normal temperature environment.

7. The test method of the microcontroller embedded voltage reference and temperature sensor test device according to claim 1, characterized in that: Erasing and programming the microcontroller includes the following steps: 1) The PC sends an erase instruction of a set station on the test board to the lower computer through the first USB interface; 2) The lower computer performs instruction parsing and connects the common terminal to the programming port data terminal of the microcontroller of the setting station through the enable terminal and the control terminal of the second 16-way analog switch; 3) The microprocessor of the lower computer erases the microcontroller of the setting station according to the C2 protocol; 4) The microprocessor of the lower computer programs the setting station microcontroller according to the C2 protocol and downloads the self-test program into the Flash of the setting station microcontroller; 5) Return to step 1) until all 16-bit microcontrollers have completed erasing and programming.

8. The test method of the microcontroller embedded voltage reference and temperature sensor test device according to claim 7, characterized in that: The self-test program is a program executed by the microcontroller on the test board after it is powered on, including starting the voltage reference and outputting it, reading the station setting status, receiving the control word sent by the lower computer to match the setting station, starting the embedded temperature sensor and uploading the temperature sampling value to the lower computer; Each station microcontroller reserves a resistor at the same pin position, and the station is set by software through a self-test program to achieve a unified self-test program code for each station.

9. The test method of the microcontroller embedded voltage reference and temperature sensor test device according to claim 7, characterized in that: Performing a voltage benchmark test on a set station includes the following steps: (1) The PC sends a voltage reference test instruction for a set station on the test board to the lower computer through the first USB interface; (2) The lower computer performs instruction parsing, and connects the common terminal to the voltage reference output terminal of the setting station microcontroller through the enable terminal and the control terminal of the first 16-way analog switch, so that the voltage reference output terminal of the setting station is connected to the digital multimeter. (3) The PC reads the measurement value of the digital multimeter through the second USB interface, and performs identification, storage and display; (4) Return to step (2) until all 16-position microcontrollers have completed the voltage benchmark test.

10. The test method of the microcontroller embedded voltage reference and temperature sensor test device according to claim 7, characterized in that: Performing a temperature sensor test on a set station includes the following steps: ① The PC sends a voltage reference test instruction for a set station on the test board to the lower computer through the first USB interface; ② The lower computer parses the instruction and matches the setting station. After the matching is successful, the microcontroller of the setting station starts the temperature sensor and sends the temperature sampling value to the microprocessor of the lower computer through the second UART interface, and then uploads it to the PC through the USB to serial port chip; ③The PC determines, stores and displays the temperature sampling values. ④ Return to step ① until all 16-bit microcontrollers have completed the voltage benchmark test.

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