PIS screen power panel testing device

Abstract

The utility model relates to the technical field of detection equipment, and discloses a PIS screen power panel testing device, which comprises an input voltage and current measuring module; a PFC circuit voltage measurement module; an on-off driving module; and the voltage output channel comprises a voltage and current measurement module and a voltage output electronic load module. According to the utility model, whether the PFC circuit works normally or not can be judged according to the input voltage and the input current of the power panel and the filter capacitor voltage of the PFC circuit, whether the Power-ON starting pin can be started or shut down normally or not, and the measurement work of the output voltage and the current of the 20V, 3.5 V and 12V voltage output pins and on-load test can be completed, the operation is simple, the test is convenient, and the safety risk is small.

Description

TECHNICAL FIELD

[0001] The utility model relates to test equipment technical field more specifically, the utility model relates to PIS screen power panel testing arrangement. BACKGROUND

[0002] PIS system, also known as passenger information system, is a multimedia integrated information system relying on multimedia network technology, taking computer system as core, allowing passengers to understand train operation information and public media information in time and accurately through media equipment arranged in station hall, platform and train passenger room. PIS system is widely used in platform train arrival countdown display, train site information in carriage, video media advertisement and emergency state information release, including train broadcast, internal display, V screen, carriage monitoring, emergency call equipment, etc.

[0003] At present, 90% of PIS screen brightness is substandard, which produces problems such as low display information picture quality and poor passenger experience. According to equipment performance characteristics, the key points of screen life and brightness reduction are screen backlight tube aging and liquid crystal aging. Therefore, a new type of LED driver backlight is developed according to PIS screen, a batch of new backlight components are made, and testing is carried out after installation. After more than a year of actual testing in stations, batch upgrading is carried out.

[0004] During batch upgrading, LED drive board needs to be replaced, and PIS screen LED backlight driver testing device is designed and made for the convenience of batch production and function testing. During batch upgrading, original PIS screen liquid crystal panel, main control board and original power board are used for circuit technology upgrading and transformation. Therefore, the power board and the main control board need to be cleaned and the power board performance needs to be tested under load. Avoiding faults after assembly, causing repair delay.

[0005] The PIS screen power board that needs to be technically upgraded has multiple different voltage outputs for AC220V input, so the output interface needs to be functionally configured and tested. According to the definition of power board P201 interface after PIS screen technology upgrading, the power board can start after Pin1 (Power-ON) is electrically connected to 3.5V, and the corresponding output voltage is output to GND after the circuit starts. If the output voltage deviation is large, there is no output voltage, the output voltage fluctuates unstably, and the load capacity is insufficient, the power board is abnormal and needs to be repaired. Therefore, the function test and verification of the power board need to be completed. That is, the input voltage and input current of the power board are measured, the filter capacitor voltage of the PFC circuit is measured to determine whether the PFC circuit is working normally, whether the Pin1 (Power-ON) start pin can start or shut down normally, and the output voltage and current of the 20V, 3.5V and 12V voltage output pins are measured and load test is carried out.

[0006] 20V voltage output pin: Pin2 (20V), Pin3 (20V), Pin4 (20V); 3.5V voltage output pin: Pin9 (3.5V), Pin10 (3.5V), Pin11 (3.5V), Pin12 (3.5V);

[0007] 12V voltage output pin: Pin17 (12V), Pin19 (12V), Pin21 (12V).

[0008] In the test circuit built by the prior art, a power resistor is mostly used as an output dummy load to perform output load test, a switch is used to electrically connect the Pin1 (Power-ON) with the 3.5V pin to simulate the start and stop of the power board, and a multimeter is used to manually measure each voltage. This test method is complicated, time-consuming and laborious, and the circuit board has high voltage and large capacitance, so the operation is dangerous. Moreover, it is difficult to simultaneously measure the input voltage and input current of the power board, the filter capacitor voltage of the PFC circuit to determine whether the PFC circuit works normally, whether the Pin1 (Power-ON) start pin can normally start or shut down, and the output voltage and current of the 20V, 3.5V and 12V voltage output pins with load test, etc. Therefore, it is inconvenient for the operator, and thus needs to be improved. Practical new type content

[0009] In order to overcome the shortcomings of the prior art, the utility model provides a PIS screen power board test device, has the advantages such as simple operation, convenient test and small safety risk.

[0010] In order to achieve the above object, the utility model provides the following technical scheme:

[0011] The PIS screen power board test device comprises:

[0012] The input voltage and current measurement module comprises an AC input voltage and current measurement circuit, and the voltage and current of AC 220V input are detected through a voltage transformer, a current transformer and an electric energy metering chip CS5463 to realize parameter measurement of input electrical parameters.

[0013] The PFC circuit voltage measurement module comprises a PFC voltage measurement circuit, and the voltage is divided through a resistance network, then converted into digital quantity through the ADC of a single-chip microcomputer, and then the digital quantity is sent to the MCU through an optical coupler.

[0014] The switch-on and switch-off driving module comprises a switch-on and switch-off driving circuit, and the switch-on and switch-off signals of the power board are simulated and controlled through the contact of a relay.

[0015] The voltage output channel voltage current measurement module comprises a 20V voltage current measurement circuit, a 12V voltage current measurement circuit and a 3.5V voltage current measurement circuit;

[0016] The voltage output electronic load module comprises a 20V electronic load circuit, a 12V electronic load circuit and a 3.5V electronic load circuit, a MOS tube IRF3205 is used as a power tube, a 0.1R alloy resistor is used as a current sampling resistor, and a constant current driving circuit is formed by using an operational amplifier MCP6001.

[0017] As a preferred technical scheme of the utility model, the PFC circuit voltage measurement module further comprises a DC-DC isolation power supply for isolating the voltage of the PIS screen power supply board and supplying power to the PFC voltage measurement circuit.

[0018] As a preferred technical scheme of the utility model, the PFC circuit voltage measurement module further comprises an LDO reference power supply for generating a reference voltage 3.3V to supply power to the single-chip microcomputer in the PFC voltage measurement circuit.

[0019] As a preferred technical scheme of the utility model, the 20V voltage current measurement circuit measures the output voltage of the MCU through resistance voltage division and detection by the ADC, and the current measurement is connected in series with a current sampling resistor at the 20V output end, converts the current into voltage, converts the analog voltage by using an INA193 current sampling chip, and detects by the ADC of the MCU to realize current measurement.

[0020] As a preferred technical scheme of the utility model, the 12V voltage current measurement circuit measures the output voltage of the MCU through resistance voltage division and detection by the ADC, and the current measurement is connected in series with a current sampling resistor at the 12V output end, converts the current into voltage, converts the analog voltage by using an INA193 current sampling chip, and detects by the ADC of the MCU to realize current measurement.

[0021] As a preferred technical scheme of the utility model, the 3.5V voltage current measurement circuit measures the output voltage of the MCU through resistance voltage division and detection by the ADC, and the current measurement is connected in series with a current sampling resistor at the 3.5V output end, converts the current into voltage, converts the analog voltage by using an INA193 current sampling chip, and detects by the ADC of the MCU to realize current measurement.

[0022] As a preferred technical scheme of the utility model, the MCU main control unit comprises an MCU, which is a main controller and completes the control and detection of related functions.

[0023] Compared with the prior art, the utility model has the beneficial effects as follows:

[0024] The utility model discloses a input voltage current measurement module, PFC circuit voltage measurement module, switch on and off drive module, voltage output channel voltage current measurement module and voltage output electronic load module can complete to power panel's input voltage, input current, PFC circuit's filter capacitor voltage judges whether PFC circuit is normal work, power -on start pin whether can normal start or shutdown and 20V, 3.5V and 12V voltage output pin's output voltage and current and take load test's measurement work, simple operation, convenient test, small safety risk. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is the overall block diagram of the utility model.

[0026] Figure 2 It is the MCU circuit diagram of the utility model.

[0027] Figure 3 It is the voltage transformer, current transformer circuit diagram of the utility model.

[0028] Figure 4 It is the electric energy metering chip circuit diagram of the utility model.

[0029] Figure 5 It is the PFC voltage measurement circuit diagram of the utility model.

[0030] Figure 6 It is the DC-DC isolation power supply circuit diagram of the utility model.

[0031] Figure 7 It is the switch on and off drive circuit diagram of the utility model.

[0032] Figure 8 It is the 20V voltage current measurement circuit diagram of the utility model.

[0033] Figure 9 It is the 12V voltage current measurement circuit diagram of the utility model.

[0034] Figure 10 It is the 3.5V voltage current measurement circuit diagram of the utility model.

[0035] Figure 11 It is the 20V electronic load circuit diagram of the utility model.

[0036] Figure 12 It is the 12V electronic load circuit diagram of the utility model.

[0037] Figure 13 It is the 3.5V electronic load circuit diagram of the utility model.

[0038] Figure 14The power circuit diagram of the utility model.

[0039] Figure 15 The display circuit diagram of the utility model.

[0040] Figure 16 The USB interface circuit diagram of the utility model.

[0041] Figure 17 The buzzer circuit diagram of the utility model. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the utility model will be apparently and completely described below with reference to the drawings in the embodiments of the utility model. Apparently, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all the other embodiments obtained by the person skilled in the art without creative labor fall within the protection scope of the utility model.

[0043] Embodiment 1

[0044] As Figures 1 to 13 shown, the utility model provides PIS screen power panel test device, including having:

[0045] MCU main control unit, including MCU, for main controller, the control and detection of relevant function are completed;

[0046] Input voltage current measurement module, including AC input voltage current measurement circuit, through voltage transformer, current transformer and electric energy metering chip CS5463 detects the voltage and current of AC 220V input, realizes the parameter measurement of input electric parameter;

[0047] PFC circuit voltage measurement module, including PFC voltage measurement circuit, through resistance network divides, then through the ADC of singlechip carries out analog-digital conversion and becomes digital quantity, then through photoelectric coupler sends digital quantity to MCU;

[0048] Switching machine drive module, including switching machine drive circuit, through the contact point simulation of relay controls the switching machine signal of power panel;

[0049] Voltage output channel voltage current measurement module, including 20V voltage current measurement circuit, 12V voltage current measurement circuit and 3.5V voltage current measurement circuit;

[0050] Voltage output electronic load module, including 20V electronic load circuit, 12V electronic load circuit and 3.5V electronic load circuit, through MOS tube IRF3205 as power tube, 0.1R alloy resistance as current sampling resistance, uses operational amplifier MCP6001 to constitute constant current drive circuit.

[0051] Among them, reference Figure 3 and Figure 4 The AC input voltage and current measurement circuit uses a voltage transformer and a current transformer, along with the CS5463 energy metering chip, to detect the voltage and current of the 220V AC input, thereby measuring the input electrical parameters. The AC input voltage and current measurement circuit measures the common factors of voltage and current, as well as the frequency and electrical parameters, on the 220V input circuit board. The CS5463 performs energy metering, collecting the input voltage and current through the voltage and current transformers to measure the 220V AC electrical parameters. After measurement, the corresponding values ​​are output and transmitted to the microcontroller.

[0052] Among them, reference Figure 5 and Figure 6 The PFC voltage measurement circuit uses a DC-DC isolated power supply to generate an isolated 5V voltage, which is used to isolate and measure the voltage of the PIS screen power supply board and supply power to the LDO reference power supply. The LDO reference power supply generates a reference voltage of 3.3V to provide a reference reference voltage of 3.3V for the measurement circuit, and supplies power to the single-chip microcomputer in the PFC voltage measurement circuit. The STC8H2K08U single-chip microcomputer is used to realize the ADC conversion to digital quantity. Isolated measurement is because the electricity of the measuring device and the electricity in the power supply board cannot be directly connected and measured, and isolated measurement is required. Direct measurement will affect the power supply board being measured, so the measurement circuit requires isolated power supply and isolated acquisition. In the circuit diagram, the DC-DC isolated power supply supplies power to the measurement circuit, and then generates a collective voltage through the LDO reference power supply circuit, thereby supplying power to the single-chip microcomputer of the measurement circuit. The voltage reference can improve the accuracy of the measurement circuit.

[0053] The voltage measurement circuit uses a resistor network to reduce the voltage and achieve high voltage attenuation and measurement. The serial port isolation communication circuit realizes the digital value converted by the ADC of the PFC voltage measurement circuit and transmits it through an optical coupler for isolated transmission. This achieves the purpose of isolated measurement and transmission and realizes electrical isolation.

[0054] The principle is that the voltage is measured through the voltage measuring circuit, divided by the resistor network, and then converted into digital quantity by the ADC of the microcontroller. After being converted into digital quantity, the digital quantity is sent to the central control unit through the optocoupler.

[0055] Among them, reference Figure 7 The power-on / off drive circuit uses relay contacts to simulate the control of the power board's power-on / off signal. When the relay contacts close, VOUT3.5 and Power-ON are short-circuited, closing the 3.5V and power-on ports, enabling the power-on function.

[0056] Among them, reference Figure 8The 20V voltage and current measurement circuit measures the output voltage to the ADC of the MCU through resistance voltage division, current measurement is carried out on the 20V output end in series with a current sampling resistor, after current is converted into voltage, INA193 current sampling chip is used to convert into analog voltage, detection is carried out through the ADC of the MCU, and current measurement is realized.

[0057] The reference Figure 9 The 12V voltage and current measurement circuit measures the output voltage to the ADC of the MCU through resistance voltage division, current measurement is carried out on the 12V output end in series with a current sampling resistor, after current is converted into voltage, INA193 current sampling chip is used to convert into analog voltage, detection is carried out through the ADC of the MCU, and current measurement is realized.

[0058] The reference Figure 10 The 3.5V voltage and current measurement circuit measures the output voltage to the ADC of the MCU through resistance voltage division, current measurement is carried out on the 3.5V output end in series with a current sampling resistor, after current is converted into voltage, INA193 current sampling chip is used to convert into analog voltage, detection is carried out through the ADC of the MCU, and current measurement is realized.

[0059] The reference Figure 11 The 20V electronic load circuit uses MOS tube IRF3205 as a power tube, 0.1R alloy resistance as a current sampling resistor, uses operational amplifier MCP6001 to constitute a constant current driving circuit, different voltage values are output from the DAC1 of the MCU, thereby realizing load simulation of different constant current values, and thereby realizing the purpose of consuming output power supply.

[0060] The reference Figure 12 The 12V electronic load circuit uses MOS tube IRF3205 as a power tube, 0.1R alloy resistance as a current sampling resistor, uses operational amplifier MCP6001 to constitute a constant current driving circuit. Different voltage values are output from the DAC2 of the MCU, thereby realizing load simulation of different constant current values, and thereby realizing the purpose of consuming output power supply.

[0061] The reference Figure 13 The 3.5V electronic load circuit uses MOS tube IRF3205 as a power tube, 0.1R alloy resistance as a current sampling resistor, uses operational amplifier MCP6001 to constitute a constant current driving circuit. Different voltage values are output from the DAC3 of the MCU, thereby realizing load simulation of different constant current values, and thereby realizing the purpose of consuming output power supply.

[0062] The working principle and use flow of the utility model are as follows:

[0063] According to Figure 1The main block diagram can be seen that in the MCU master unit is a master control, through the MCU master unit can realize the test of each module in turn, such as input voltage current measurement module, which is used to measure the voltage and current of the input power board, that is, to measure the voltage and current of AC 220V, the filter capacitor voltage in the PFC circuit voltage measurement module can judge whether the PFC circuit works normally, through the switch on-off driving module, it can be judged whether the start pin can start normally or shut down, the voltage output channel voltage current measurement module realizes the measurement of the voltage and current of the 20V, 12V, 3.5V output pin voltage and current in the circuit board;

[0064] The overall working principle is to measure the input AC 220V power board voltage and current, as well as the PFC voltage circuit and 20V, 12V, 3.5V voltage and current, and control the 20V, 12V, 3.5V electronic load, so as to realize the input AC voltage and current, PFC voltage, 20V, 12V, 36V voltage and current parameters, and realize the control of the switch-on-off circuit.

[0065] Embodiment 2

[0066] Reference Figure 14 It also includes a power supply circuit module, including a power supply circuit, which is used to input 36V voltage step-down output 5V and 3.3V to power the test device.

[0067] Reference Figure 15 It also includes a display circuit module, including a display circuit, which uses DWINK600 serial screen as a display unit. As a display interface for testing.

[0068] Reference Figure 16 It also includes a USB interface module, including a USB interface circuit, which is a USB to TTL serial circuit and a one-key download circuit, realizing the program firmware download and upgrade function of MCU. Used for communication.

[0069] Reference Figure 17 It also includes a buzzer module, including a buzzer and a buzzer circuit for driving. The buzzer circuit drives the buzzer through a triode, and the buzzer is connected in parallel with a resistor and a light emitting diode. When the buzzer is ringing, the light emitting diode will follow the light. The signal of MCU can drive the triode, thereby driving the buzzer and the indicator light.

[0070] It is to be noted that, in the present document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0071] While the embodiments of the present application have been illustrated and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and alterations can be made therein without departing from the spirit and scope of the application, which is defined by the appended claims and their equivalents.

Claims

1. PIS screen power board testing device, characterized in that, Includes: The input voltage and current measurement module includes an AC input voltage and current measurement circuit, which detects the AC 220V input voltage and current through a voltage transformer, a current transformer, and a power metering chip CS5463 to measure the input electrical parameters. The PFC circuit voltage measurement module includes a PFC voltage measurement circuit, which divides the voltage through a resistor network, converts the analog-to-digital value through the ADC of the microcontroller, and then sends the digital value to the MCU through an optocoupler; The power on / off drive module includes a power on / off drive circuit that simulates the control of the power on / off signal of the power board through the contacts of the relay; Voltage output channel voltage and current measurement module, including 20V voltage and current measurement circuit, 12V voltage and current measurement circuit and 3.5V voltage and current measurement circuit; The voltage output electronic load module includes a 20V electronic load circuit, a 12V electronic load circuit, and a 3.5V electronic load circuit. It uses the MOS tube IRF3205 as a power tube, a 0.1R alloy resistor as a current sampling resistor, and an op amp MCP6001 to form a constant current drive circuit.

2. The PIS screen power board testing device according to claim 1, characterized in that: The PFC circuit voltage measurement module also includes a DC-DC isolation power supply, which is used to isolate and measure the voltage of the PIS screen power supply board and supply power to the PFC voltage measurement circuit.

3. The PIS screen power board testing device according to claim 2, characterized in that: The PFC circuit voltage measurement module also includes an LDO reference power supply, which generates a reference voltage of 3.3V to power the single-chip microcomputer in the PFC voltage measurement circuit.

4. The PIS screen power board testing device according to claim 1, characterized in that: The 20V voltage and current measurement circuit measures the output voltage through resistor voltage division and sends it to the MCU's ADC for detection. The current measurement connects a current sampling resistor in series with the 20V output end, converts the current into voltage, uses the INA193 current sampling chip to convert it into an analog voltage, and detects it through the MCU's ADC to achieve current measurement.

5. The PIS screen power board testing device according to claim 1, characterized in that: The 12V voltage and current measurement circuit measures the output voltage through resistor voltage division and sends it to the MCU's ADC for detection. The current measurement connects a current sampling resistor in series with the 12V output end, converts the current into voltage, uses the INA193 current sampling chip to convert it into an analog voltage, and detects it through the MCU's ADC to achieve current measurement.

6. The PIS screen power board testing device according to claim 1, characterized in that: The 3.5V voltage and current measurement circuit measures the output voltage through resistor voltage division and sends it to the MCU's ADC for detection. The current measurement connects a current sampling resistor in series with the 3.5V output end, converts the current into voltage, uses the INA193 current sampling chip to convert it into an analog voltage, and detects it through the MCU's ADC to achieve current measurement.

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