Automatic voltage monitoring core board and voltage monitoring method thereof

Abstract

The invention provides a core board capable of automatically monitoring voltage and a voltage monitoring method thereof, the core board comprises a PMIC power management module and a main control chip, and the core board further comprises a voltage monitoring module for monitoring the input voltage and the output voltage of the PMIC power management module in the core board in real time. According to the voltage monitoring method, voltage monitoring is carried out on the core board. According to the core board and the voltage monitoring method thereof, warning information is sent out when abnormal voltage exists, meanwhile, the EN pin of the PMIC is closed, and the self-protection function is achieved. Maintenance technicians can conveniently locate problems, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to a core board and a voltage monitoring method thereof, in particular to a core board for automatic voltage monitoring and a voltage monitoring method thereof. Background Art

[0002] This section merely provides background information related to the present disclosure and is not necessarily prior art.

[0003] Terminal products such as concentrators, special transformers, and energy controllers in the power industry are mainly used for meter data collection and have high reliability requirements. The core board ADC voltage collection of existing product solutions is mainly used for backup power supply supercapacitors, backup power supply lithium batteries, and RTC clock battery voltage collection. There is no monitoring and protection for the core board's own voltage.

[0004] After inspection, it was found that the main chip, DDR, and EMMC voltages of the faulty products in the above terminal products were abnormal but they were still running; some had a white screen phenomenon; some had repeated SPL restarts; some had EMMC data loss, some had kernel programs running away, some were normal at normal temperatures, but programs running away at high temperatures, and other fault phenomena. Most of these phenomena are related to the key voltage of the core board. The faulty core board currently has the following technical problems:

[0005] 1. Most core boards adopt multi-layer board design, integrating key components such as main control, DDR, eMMC, PMIC, and some 0201 and 0402 small package resistors and capacitors. Key components are mostly packaged in BGA packaging. Mass production is prone to quality problems such as cold soldering and short circuits, making maintenance and troubleshooting more difficult.

[0006] 2. The core board has passed the production test in the factory, and needs to be burned twice before being mounted on the mainboard. After the core board is burned twice and mounted on the mainboard, defective products are still found. It is not easy to distinguish whether it is a problem with the original factory or damage caused during the secondary production process.

[0007] 3. After the whole machine is assembled and tested, it fails after being installed on site and running for a period of time, and it is difficult to analyze the cause.

[0008] Some of the above core board failures are caused by changes in IO port impedance or breakdown damage, some are power supply anomalies, and some are chip anomalies. Generally, they are related to production quality control, production process, component quality, etc. These failures can be monitored through key voltages on the core board, such as several key voltages based on the Wan Gao V8130L terminal core board (ARM7 core): main chip core voltage 1.2V, DDR3L chip voltage 1.35V, EMMC chip voltage 1.8V and 3.3V, peripheral voltage 3.3V, core board input voltage 5V. During the production process, maintenance personnel can locate the cause of the problem based on the printed voltage fault alarm information, improve production efficiency, and reduce the maintenance personnel's fault judgment time. At the operation site, voltage anomalies are warned in advance, and the faulty core board can be located in what time period according to the abnormal alarm log information, which is helpful for FAE to analyze and troubleshoot problems.

[0009] Currently, the existing power terminal core board does not have a voltage self-detection function, and the relevant technical standards do not force monitoring. The ADC sampling function on the core board is used to detect and monitor the peripheral backup power supply, such as lithium battery voltage, backup power supply super capacitor voltage and clock battery voltage, but does not monitor the core board's own voltage.

[0010] In the prior art: "Detection circuit and detection method for confirming the working power supply voltage of MCU", publication number 202010064185.8, proposes a detection circuit and detection method for confirming the working power supply voltage of MCU. However, this technical solution only detects the input voltage of MCU powered by a single power supply, and fails to solve the abnormal voltage problem of the core board based on the PMIC power management module, which has multiple voltages such as the main chip, EMMC, DDR, etc.

[0011] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0012] Purpose of the invention: The technical problem to be solved by the present invention is to provide a core board for automatic voltage monitoring and a voltage monitoring method thereof in view of the deficiencies in the prior art.

[0013] In order to solve the above technical problems, the present invention discloses a core board for automatic voltage monitoring and a voltage monitoring method thereof, including a PMIC power management module and a main control chip. The core board also includes: a voltage monitoring module for real-time monitoring of the input voltage and output voltage of the PMIC power management module in the core board.

[0014] Furthermore, the input voltage and output voltage of the PMIC power management module include:

[0015] Input a 5V voltage to the PMIC power management module;

[0016] The PMIC power management module outputs 1.2V voltage, 1.35V voltage, 1.8V voltage and 3.3V voltage.

[0017] Furthermore, the voltage monitoring module includes:

[0018] The 5-channel ADC sampling circuits respectively monitor the 5V input voltage and 1.2V, 1.35V, 1.8V and 3.3V output voltages of the PMIC power management module in real time.

[0019] Furthermore, the 5-channel ADC sampling circuit uses the ADC sampling module in the core board, or adopts an ADC expansion solution to perform ADC voltage sampling.

[0020] Furthermore, the ADC expansion solution specifically includes:

[0021] The main control chip U1, the first extended ADC conversion chip U2 and the second extended ADC conversion chip U3 are connected via an IIC bus to form an ADC expansion solution.

[0022] Furthermore, the first extended ADC conversion chip U2 and the second extended ADC conversion chip U3 both adopt MS5175 chips.

[0023] Furthermore, the first pin, the second pin, the fourth pin and the fifth pin of the first extended ADC conversion chip U2 receive the sampling power supply network, the sixth pin is connected to the 3.3V power supply and is externally connected to the C12 decoupling capacitor, the seventh pin and the eighth pin are respectively connected to the IIC bus interface and are pulled up to 3.3V voltage through the first resistor R20 and the second resistor R21, and the ninth pin and the tenth pin are respectively pulled down to the ground GND;

[0024] The first pin of the second extended ADC conversion chip U3 receives the sampling power supply network, the sixth pin is connected to the 3.3V power supply and is externally connected to the C12 decoupling capacitor, the seventh pin and the eighth pin are respectively connected to the IIC bus interface and are pulled up to 3.3V voltage through the first resistor R20 and the second resistor R21, the ninth pin is pulled down to the ground GND, and the tenth pin is connected to the 3.3V power supply.

[0025] Furthermore, the power supply network to be sampled is a set of 1.2V voltage, 1.35V voltage, 1.8V voltage, 3.3V voltage and 5V voltage to be detected.

[0026] Furthermore, in the ADC sampling circuit, the ADC sampling circuit for monitoring the 5V voltage also includes a protection circuit, which uses a protection diode D1 for protection.

[0027] The present invention also provides a voltage monitoring method for a core board with automatic voltage monitoring, and the voltage monitoring of the core board includes the following steps:

[0028] Step 1, before power-on, the core board is powered on, and the voltage monitoring module detects the input voltage. If the input voltage is greater than the first input threshold V ovp , overvoltage protection is performed and the output of the PMIC power management module is turned off; if the input voltage is less than the second input threshold V uvp , then undervoltage protection is performed and the output of the PMIC power management module is turned off;

[0029] Step 2: During the SPL startup phase, the UBOOT startup phase, and the Kernel startup phase, the voltage monitoring module monitors the output voltage of the PMIC power management module. If the output voltage reaches the output threshold, the enable EN pin of the PMIC power management module is controlled to turn off the output of the PMIC power management module, and the abnormal voltage value is recorded, and an alarm is issued at the same time;

[0030] Step 3, during the continuous operation stage of the core board, the voltage monitoring module continuously monitors the output voltage of the PMIC power management module. If the output voltage reaches the output threshold, the enable EN pin of the PMIC power management module is controlled to shut down the output of the PMIC power management module, and the abnormal voltage value is recorded, and an alarm is issued at the same time.

[0031] Beneficial effects:

[0032] 1. The core board voltage proposed in the present invention is automatically monitored, and an alarm message is issued if there is an abnormal voltage, and the PMICEN pin is closed at the same time to realize the self-protection function.

[0033] 2. When the core board proposed by the present invention is produced, the startup information is used to check which voltage is the fault point, which facilitates the maintenance technicians to locate the problem and improves production efficiency.

[0034] 3 The core board proposed by the present invention can continuously run the prototype on site, and issue an alarm message when a voltage failure occurs, and save it in the log at the same time. The operation and maintenance personnel can query at which link the problem occurs according to the log. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0036] Figure 1 This is a schematic diagram of the core board power supply topology.

[0037] Figure 2 This is a schematic diagram of the core board power supply voltage ADC voltage sampling circuit.

[0038] Figure 3 This is a schematic diagram of the ADC expansion solution.

[0039] Figure 4 This is a schematic diagram of the core board voltage automatic detection process.

[0040] Figure 5 Schematic diagram of ADC sampling threshold range. DETAILED DESCRIPTION

[0041] The overall design idea of ​​the present invention is as follows: In the power industry, terminal products such as concentrators, special transformers, and energy controllers are mainly used for meter data collection, and high reliability is required. The core board ADC voltage collection of existing product solutions is mainly used for backup power supply supercapacitors, backup power supply lithium batteries, and RTC clock battery voltage collection. There is no monitoring and protection for the core board's own voltage.

[0042] Some faulty products are found to have abnormal voltages of the main chip, DDR, and EMMC but are still running; some have white screen phenomenon; some have repeated restarts of SPL; some have EMMC data loss, some have kernel programs running away, some are normal at normal temperature, and high temperature programs running away, etc. These phenomena are mostly related to the key voltage of the core board. The core board of the present invention has its own voltage monitoring function, which can monitor its own voltage operation status in real time.

[0043] The voltage anomaly of the core board changes slowly, and an early warning can be issued. The voltage anomaly does not suddenly change at the beginning. For example, the EMMC power supply adopts the PMIC BUCK circuit. If the FB voltage divider resistor is poorly soldered or the parallel capacitor is slightly damaged and not detected in the factory, the product will be hung on site. Over time, the output voltage may change beyond the threshold range. The present invention has a voltage self-monitoring function that can issue an early warning to detect problems in time.

[0044] The problem of the product may be introduced during the production process or in subsequent applications, and needs to be traced back to analyze the link where the problem occurred. The present invention monitors the voltage anomaly information in real time and saves it in the log, which is convenient for subsequent problem analysis and tracing.

[0045] According to the above ideas, the overall design of the present invention is as follows:

[0046] 1) The core board is equipped with multiple voltage sampling circuits to realize abnormal voltage monitoring of key devices such as main control, DDR, EMMC, and peripherals.

[0047] 2) When the core board exceeds the abnormal threshold, it will issue an alarm message and shut down the PMIC to achieve its own protection function.

[0048] 3) Voltage monitoring is divided into three stages, and the purpose or use of monitoring in each stage is different. In the first stage, overvoltage and undervoltage protection are realized through PMIC + voltage monitoring chip. In the second stage, abnormal voltage alarm is realized through ADC interrupt, which is convenient for production maintenance and troubleshooting. The third stage is used for on-site prototype fault monitoring. Abnormal voltage is saved in the operation log, which is convenient for tracing the faulty machine to find out which link has the problem.

[0049] 4) The ADC sampling circuit is implemented through a voltage divider resistor. A protection diode is added to the ADC sampling of the PMIC input 5V voltage to prevent the lower voltage divider resistor from being damaged and exceeding the operating voltage range of the ADC circuit.

[0050] The specific technical solutions of the present invention are as follows:

[0051] 1. Core board power supply topology:

[0052] like Figure 1 As shown, the core boards of terminal products such as concentrators, special transformers, and energy controllers in the power industry generally include PMIC power management chips, main control chips, EMMC chips, DDR chips, and some peripheral circuits, such as ESAM, FLASH, etc. Figure 1 It is the core board power supply topology. The power supply adopts PMIC chip. The 5V input end has a voltage detection chip to provide low voltage protection. The output end outputs 1.2V, 1.35V, 1.8V, and 3.3V at the same time, which are respectively used for main control, EMMC, DDR, and peripheral power supply.

[0053] 2. Core board power ADC sampling circuit:

[0054] like Figure 2 As shown, the core board power supply voltage monitoring is implemented by using the ADC channel in the chip for voltage sampling. For example, in one embodiment, the V8130L chip of a core board uses the ARM Cortex-A7 core architecture with 8-channel ADC sampling. The following 5-channel ADC is used to collect the PMIC input voltage of 5V and the output voltages of 1.2V, 1.35V, 1.8V, and 3.3V respectively.

[0055] The core board referred to in the present invention refers to the core board used in the power collection terminal, which generally has peripherals such as pmic, main control, ddr, emmc, etc. ADC sampling belongs to the basic application, and the ADC channel varies according to the selected chip resources.

[0056] If the ADC sampling channels in the core board chip are not enough, an expansion chip solution can be adopted to expand the ADC sampling to IIC. In one embodiment, the ADC expansion solution that can be adopted is as follows: Figure 3As shown, use the 4-channel single-ended input channel ADC sampling conversion chip MS5175. If 4 channels are not enough, you can choose 2 expansion chips. Through ASEL0, ASEL0 address chip select read ADC sampling data. The solution is as follows Figure 3 As shown:

[0057] U1 is the main control chip, U2 and U3 are extended ADC conversion chips, which are connected through the IIC bus. U2MS5175PIN1,2,4,5 pins are connected to the ADC sampling power supply network, PIN6 is a 3.3V power supply, an external C12 decoupling capacitor, PIN7,8 are IIC bus interfaces pulled up to 3.3V through R20, R21 resistors, and PIN9,10 chip select pins are pulled down to GND. Similarly, U3 PIN1 is connected to the sampling power supply network, PIN6 is a 3.3V power supply, an external C13 decoupling capacitor, PIN7,8 are IIC bus interfaces pulled up to 3.3V through R20, R21 resistors, PIN9 chip select is pulled down to GND, and PIN10 chip select pin is connected to 3.3V.

[0058] The 5V input voltage ADC voltage divider resistor is used to prevent the lower voltage divider resistor from being cold-soldered, causing the sampling voltage to exceed the ADC sampling voltage range and damage the chip. A D1 protection circuit is added.

[0059] The 5.0V power supply obtains the sampling signal ADC5.0 through the resistor voltage divider R1 and R2, C1 is the filter capacitor, and D1 is the protection diode. If the voltage divider resistor R5 is poorly soldered, if there is no D1 protection diode, the ADC5.0 sampling voltage will be pulled to 5V, resulting in the sampling voltage exceeding the chip ADC operating voltage range. Since one of the cathodes of the D1 double protection diode is connected to 3.3V, the ADC5.0 voltage is clamped at about 3.8V using the diode voltage clamping characteristics. If there is a negative voltage in ADC5.0, because one of the anodes of the D1 double protection diode is connected to GND, the ADC5.0 sampling voltage will also be clamped at about -0.5V, thereby limiting the sampling voltage to between -0.5V and 3.8V, achieving a protective effect.

[0060] 3. Flow chart of the detection method, such as Figure 4 As shown:

[0061] The core board voltage automatic detection process includes three stages: 1. The stage before power-on startup; 2. The SPL, UBOOT, and Kernel startup stages; 3. The system startup app continuous operation stage.

[0062] Voltage anomalies are monitored at each stage. In the first stage, undervoltage and overvoltage protection are realized through dual protection of PMIC + voltage detection chip. In the second stage, the SPL, UBOOT, and Kernel startup stages, the ADC sampling circuit is used to configure the ADC register to set the voltage monitoring threshold, and the ADC interrupt voltage monitoring is started. When the monitoring threshold is exceeded, the alarm voltage is printed and output, and then the PMICEN pin is controlled to turn off the power. The third stage is the continuous operation stage after the system is started. When an abnormal voltage occurs, the alarm voltage is printed and saved to the log file, and then the PMIC EN pin is controlled to turn off the power.

[0063] 4. ADC voltage sampling threshold

[0064] Each ADC sampling has a sampling threshold range, such as the core 1.2V voltage, setting Figure 5 As shown, when the threshold protection range is exceeded, an alarm message is issued. According to the extreme working voltage range given in the chip data sheet, set the upper and lower thresholds. When setting, you can reserve some margins according to the commissioning situation. For example, the upper threshold Vovp of the main control V8130L 1.2V voltage is set to 1.3V, and the lower threshold Vuvp is 1.1V; the upper threshold Vovp of the DDR3L 1.35V voltage is set to 1.45V, and the lower threshold Vuvp is 1.3V; the upper threshold Vovp of the EMMC 1.8V voltage is set to 1.90V, and the lower threshold Vuvp is 1.7V; the upper threshold Vovp of the 3.3V voltage is set to 3.6V, and the lower threshold Vuvp is 2.7V.

[0065] In a specific implementation, the present application provides a computer storage medium and a corresponding data processing unit, wherein the computer storage medium can store a computer program, and when the computer program is executed by the data processing unit, the invention content of a core board for automatic voltage monitoring and a voltage monitoring method thereof provided by the present invention and some or all of the steps in each embodiment can be executed. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0066] Those skilled in the art can clearly understand that the technical solutions in the embodiments of the present invention can be implemented by means of computer programs and their corresponding general hardware platforms. Based on such an understanding, the technical solutions in the embodiments of the present invention can be essentially or partly contributed to the prior art in the form of computer programs, i.e., software products, which can be stored in a storage medium and include several instructions for enabling a device including a data processing unit (which can be a personal computer, a server, a single-chip microcomputer, an MCU or a network device, etc.) to execute the methods described in various embodiments of the present invention or certain parts of the embodiments.

[0067] The present invention provides a core board for automatic voltage monitoring and a method for voltage monitoring thereof. There are many methods and approaches to implement the technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A core board for automatic voltage monitoring, including a PMIC power management module and a main control chip, characterized in that: The core board includes: a voltage monitoring module, which monitors the input voltage and output voltage of the PMIC power management module in the core board in real time.

2. A core board for automatic voltage monitoring according to claim 1, characterized in that: The input voltage and output voltage of the PMIC power management module include: Input a 5V voltage to the PMIC power management module; The PMIC power management module outputs 1.2V voltage, 1.35V voltage, 1.8V voltage and 3.3V voltage.

3. A core board for automatic voltage monitoring according to claim 2, characterized in that: The voltage monitoring module comprises: The 5-channel ADC sampling circuits respectively monitor the 5V input voltage, and 1.2V, 1.35V, 1.8V and 3.3V output voltages of the PMIC power management module in real time.

4. A core board for automatic voltage monitoring according to claim 3, characterized in that: The 5-channel ADC sampling circuit uses the ADC sampling module in the core board, or adopts an ADC expansion solution to perform ADC voltage sampling.

5. A core board for automatic voltage monitoring according to claim 4, characterized in that: The ADC expansion solution specifically includes: The main control chip U1, the first extended ADC conversion chip U2 and the second extended ADC conversion chip U3 are connected via an IIC bus to form an ADC expansion solution.

6. A core board for automatic voltage monitoring according to claim 5, characterized in that: The first extended ADC conversion chip U2 and the second extended ADC conversion chip U3 both adopt MS5175 chips.

7. A core board for automatic voltage monitoring according to claim 6, characterized in that: The first pin, the second pin, the fourth pin and the fifth pin of the first extended ADC conversion chip U2 receive the sampling power supply network, the sixth pin is connected to the 3.3V power supply and is externally connected to the C12 decoupling capacitor, the seventh pin and the eighth pin are respectively connected to the IIC bus interface and are pulled up to 3.3V voltage through the first resistor R20 and the second resistor R21, and the ninth pin and the tenth pin are respectively pulled down to the ground GND; The first pin of the second extended ADC conversion chip U3 receives the sampling power supply network, the sixth pin is connected to the 3.3V power supply and is externally connected to the C12 decoupling capacitor, the seventh pin and the eighth pin are respectively connected to the IIC bus interface and are pulled up to 3.3V voltage through the first resistor R20 and the second resistor R21, the ninth pin is pulled down to the ground GND, and the tenth pin is connected to the 3.3V power supply.

8. A core board for automatic voltage monitoring according to claim 7, characterized in that: The power supply network to be sampled is a collection of 1.2V voltage, 1.35V voltage, 1.8V voltage, 3.3V voltage and 5V voltage to be detected.

9. A core board for automatic voltage monitoring according to claim 8, characterized in that: In the ADC sampling circuit, the ADC sampling circuit for monitoring the 5V voltage also includes a protection circuit, which uses a protection diode D1 for protection.

10. A voltage monitoring method for a core board with automatic voltage monitoring, characterized in that: The voltage monitoring of the core board described in claims 1 to 9 comprises the following steps: Step 1, before power-on, the core board is powered on, and the voltage monitoring module detects the input voltage. If the input voltage is greater than the first input threshold V ovp , overvoltage protection is performed and the output of the PMIC power management module is turned off; if the input voltage is less than the second input threshold V uvp , then undervoltage protection is performed and the output of the PMIC power management module is turned off; Step 2: During the SPL startup phase, the UBOOT startup phase, and the Kernel startup phase, the voltage monitoring module monitors the output voltage of the PMIC power management module. If the output voltage reaches the output threshold, the enable EN pin of the PMIC power management module is controlled to turn off the output of the PMIC power management module, and the abnormal voltage value is recorded, and an alarm is issued at the same time; Step 3, during the continuous operation stage of the core board, the voltage monitoring module continuously monitors the output voltage of the PMIC power management module. If the output voltage reaches the output threshold, the enable EN pin of the PMIC power management module is controlled to shut down the output of the PMIC power management module, and the abnormal voltage value is recorded, and an alarm is issued at the same time.

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