Simple method for judging performance difference of GND integration and separation of different modules in circuit board

Abstract

The invention discloses a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board. The method comprises the steps of S1, experiment preparation; a substrate processing and testing tool; the method comprises the following steps of S1, performing GND integration setting and testing, S2, performing GND separation setting and testing, S4, performing performance difference analysis, performing power supply stability analysis, comparing measurement data of power supply node voltage fluctuation under GND integration and GND separation conditions, comprehensively considering actual application requirements and performance requirements of a circuit board, and judging which mode of GND integration or separation is more suitable for the circuit board. The switching of the GND connection modes of the whole substrate is realized by changing the GND layer in the test, the substrate is firstly subjected to circuit design according to the independent mode of each GND, then on the basis, each independent GND of the second layer is integrated into a whole to realize the integration of the GND, solder resists with different colors are selected, the substrates with different GND connection modes are distinguished, and the test efficiency is improved. Therefore, the cost of the circuit board can be effectively controlled in the processing process of the circuit board.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit boards, and in particular to a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board. Background Art

[0002] In modern electronic circuit design, circuit boards usually contain multiple modules with different functions, and each module requires reasonable grounding to ensure its normal operation. There are two main ways of GND: integration and separation. GND integration connects the grounds of multiple modules together to form a unified ground plane, while GND separation enables each module to have an independent ground connection. In theory, the GND of each module of the substrate should be independent of each other, but due to practical limitations, such as the limited conductivity of some GNDs due to small size, it is better to integrate the GNDs together. However, it is difficult to distinguish which is better during the design stage. It is most intuitive to make a physical substrate for comparison. These two grounding methods have completely different effects on the performance of the circuit board, such as signal integrity, noise suppression, electromagnetic compatibility, and power distribution.

[0003] However, in the field of electronic circuit design, there is currently a lack of a simple, effective and accurate method to determine whether GND integration or separation can better optimize circuit performance in a specific circuit board design. Traditional evaluation methods often require complex test equipment, lengthy test processes, and professional technicians to operate and analyze data, which not only consumes a lot of time and cost, but may also lead to inaccurate evaluation results due to the complexity and uncertainty of test conditions. Therefore, this solution provides a simple method to determine the performance difference of GND integration and separation of different modules in a circuit board. Summary of the invention

[0004] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art, and to provide a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board. In the test, by changing the GND layer, the GND connection mode of the entire substrate is switched. The substrate is first designed according to the independent circuit mode of each GND, and then on this basis, the GND integration can be achieved by integrating the independent GNDs of the second layer into a whole. Different colors of solder resists are selected to distinguish substrates with different GND connection modes. Because only one layer of mold is different, effective control of the cost of circuit boards in processing is achieved.

[0005] The present invention also provides a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board, comprising the following steps: S1, experimental preparation; substrate processing: defining the experimental substrate as a four-layer substrate with double-sided mounted components, making ten-layer molds respectively, and setting the second layer as the GND layer, so as to change the GND layer in subsequent experiments and perform data comparison on the GND connection of the entire substrate; test tool: testing it through an oscilloscope, a multimeter, a spectrum analyzer, and a signal generator in the data comparison to obtain various test values;

[0006] S2, GND integration setting and testing. The circuit board is first designed according to the independent way of each GND. Then, on this basis, the independent GNDs of the second layer are integrated into a whole, and the connection is ensured to be firm and the conductivity is good. The circuit board is powered on and the experimental values ​​are recorded.

[0007] S3, GND separation setting and testing, separate the GND of different modules on the integrated substrate so that each module has an independent ground connection, repeat the power-on test operation in S2, and record the experimental data to compare the test results;

[0008] S4. Performance difference analysis: Through power supply stability analysis, compare the measured data of power supply node voltage fluctuation in the two cases of GND integration and separation. Through signal integrity analysis, observe the waveform parameters of the signal during transmission. Through noise level analysis, compare the noise power spectrum density under the two grounding methods. Finally, through comprehensive evaluation, based on the above analysis results of power supply stability, signal integrity and noise level, comprehensively consider the actual application needs and performance requirements of the circuit board, and judge whether GND integration or separation is more suitable for the circuit board.

[0009] According to the present invention, a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board is provided. The experimental substrate should include at least two modules with different functions and interrelated with each other, such as a digital signal processing module, an analog signal amplification module, and a power management module.

[0010] According to a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board provided by the present invention, when connecting the GND layer, different colors of solder resist are selected to facilitate distinguishing substrates with different GND connection methods.

[0011] According to the present invention, a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board is provided. The test tool oscilloscope has sufficient bandwidth and sampling rate, and can accurately measure the time domain waveforms of various signals on the circuit board. An oscilloscope with a bandwidth of 3-5 times or more of the operating frequency of the circuit board is selected to ensure that the rapidly changing part of the signal can be clearly captured, and the bandwidth is defined to be between 100MHz-500MHz.

[0012] According to a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board provided by the present invention, the frequency range of the test tool spectrum analyzer should cover the entire frequency band of the circuit board, and have sufficient resolution bandwidth RBW and video bandwidth VBW setting flexibility to accurately measure the signal strength and noise level at different frequencies, wherein the RBW can be set within the range of 1kHz-100kHz, and the VBW is appropriately adjusted as needed.

[0013] According to the present invention, a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board is provided. The test tool multimeter has the functions of measuring DC voltage, DC current, AC voltage and resistance. A multimeter with an accuracy of ±0.5%+digit or more is selected to ensure the accuracy of the measurement results.

[0014] According to the present invention, a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board is provided. The GND integration setting and test measures the 5V output of the power module, and the power supply voltage fluctuation peak is 50mV. An oscilloscope is used to observe the waveforms of the input signal and the output signal of the audio amplifier, and it is found that the signal distortion is small. The total harmonic distortion is calculated to be 0.5%. A spectrum analyzer is used to measure the noise level in the audio frequency band of 20Hz-100kHz, and the average noise power spectral density in the audio signal bandwidth is -60dBm / Hz.

[0015] According to the present invention, a simple method for judging the performance difference between GND integration and separation of different modules in a circuit board is provided. The GND separation setting and testing is to separate the GND of each module, repeat the test, the power supply voltage fluctuation peak becomes 80mV, the THD of the audio amplifier becomes 0.8%, and the average noise power spectrum density in the audio frequency band is -55dBm / Hz. The performance difference analysis shows that in terms of power supply stability, the voltage fluctuation is smaller and the performance is better when GND is integrated. For the audio signal quality, THD is used as a measurement indicator, and the distortion is smaller when GND is integrated, which means that the integration method is conducive to maintaining the purity of the audio signal. From the perspective of noise level, the noise in the audio frequency band is lower when GND is integrated.

[0016] Compared with the prior art, the present invention provides a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board. In the test, the GND layer is changed to switch the GND connection mode of the entire substrate. The substrate is first designed with circuits in an independent manner according to each GND. Then, on this basis, the GND integration can be achieved by integrating the independent GNDs of the second layer into a whole. Different colors of solder resists are selected to distinguish substrates with different GND connection modes. Since only one layer of mold is different, effective control of the cost of the circuit board during processing is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention is further described below in conjunction with the accompanying drawings and embodiments;

[0018] Figure 1 A flowchart of a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to the present invention;

[0019] Figure 2 A schematic diagram of a GND system for determining GND integration and separation circuits of different modules in a circuit board according to the present invention;

[0020] Figure 3 It is a schematic diagram of the GND layer in judging the GND integration and separation of different modules in a circuit board according to the present invention. DETAILED DESCRIPTION

[0021] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0022] Reference Figure 1-3 The embodiment of the present invention provides a simple method for judging the performance difference of GND integration and separation of different modules in a circuit board, characterized by:

[0023] Embodiment 1:

[0024] Experimental preparation: Select a circuit board for digital signal processing, which includes a central processing unit CPU module, a digital signal processor DSP module, a storage module and a communication interface module, etc. Prepare an oscilloscope with a set bandwidth of 200MHz, a multimeter, a spectrum analyzer with a frequency range of 1MHz-10GHz, and a signal generator that generates a variety of digital signal waveforms with a frequency range of 1kHz-1 GHz.

[0025] GND integration setup and test: Use jumpers to connect the GND of all modules together. After power on, use a multimeter to measure the voltage of the main power node to be 3.3V. Use an oscilloscope to observe the voltage fluctuation of the power node. The maximum voltage is 3.35V and the minimum voltage is 3.25V over a period of time. The peak value of the voltage fluctuation is calculated to be 100mV. Use a signal generator to input a square wave signal with a frequency of 100MHz and an amplitude of 1V to the CPU module, and observe the signal waveform at the receiving end of the DSP module through an oscilloscope. The measured signal rise time is 5ns, the fall time is 5ns, the overshoot is 100mV, and the undershoot is 80mV. Use a spectrum analyzer to measure the noise power spectral density of the circuit board in the frequency range of 1MHz-100MHz. The average noise power spectral density in the main signal bandwidth of 10MHz-50MHz is -80dBm / Hz.

[0026] GND separation setting and test: Separate the GND of each module through a pluggable connector. Power on again and perform the same test. At this time, the peak voltage fluctuation of the power node is measured to be 80mV, the signal rise time is 4ns, the fall time is 4ns, the overshoot is 80mV, the undershoot is 60mV, and the average noise power spectrum density within the main signal bandwidth is -75dBm / Hz.

[0027] Performance difference analysis: From the perspective of power supply stability, the voltage fluctuation is smaller when GND is separated, indicating that the separation method is better than the integration method in terms of power supply stability. For signal integrity, the rise time and fall time of the signal are shorter when GND is separated, and the overshoot and undershoot are also smaller, indicating that the separation method is more conducive to accurate signal transmission. In terms of noise level, the noise power spectrum density is lower when GND is separated, indicating that it has a better noise suppression effect. Taking all factors into consideration, for this digital signal processing circuit board, the GND separation method performs better in terms of power supply stability, signal integrity and noise suppression, so it is recommended to use the GND separation grounding method in actual design.

[0028] Embodiment 2:

[0029] Experimental preparation: Select an analog audio circuit board, including an audio amplifier module, an audio filter module, a power management module, etc. Prepare appropriate test instruments, an oscilloscope with a bandwidth of 150MHz, and a spectrum analyzer with a frequency range of 20Hz-100kHz.

[0030] GND integration setting and test: integrate the module GND. After power on, the peak value of the 5V power supply voltage fluctuation output by the power module is measured to be 50mV. Use an oscilloscope to observe the waveform of the audio amplifier input signal and output signal, and find that the signal distortion is small. The total harmonic distortion THD is calculated to be 0.5%. Use a spectrum analyzer to measure the noise level in the audio frequency band of 20Hz-100kHz, and the average noise power spectrum density in the audio signal bandwidth is -60dBm / Hz.

[0031] GND separation setting and test: Separate the GND of each module. Repeat the test, the power supply voltage fluctuation peak becomes 80mV, the THD of the audio amplifier becomes 0.8%, and the average noise power spectral density in the audio frequency band is -55dBm / Hz.

[0032] Performance difference analysis: In terms of power supply stability, GND integration has smaller voltage fluctuations and better performance. For audio signal quality, using THD as a measurement indicator, GND integration has smaller distortion, indicating that the integration method is conducive to maintaining the purity of the audio signal. From the perspective of noise level, GND integration has lower noise in the audio frequency band. Based on the above results, for this analog audio circuit board, the GND integration method has more advantages in power supply stability, audio signal quality and noise suppression, so the GND integrated grounding design should be adopted.

[0033] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present invention.

Claims

1. A simple method for determining the performance difference of GND integration and separation of different modules in a circuit board, comprising the following steps: S1. Experimental preparation; Substrate processing: The experimental substrate is defined as a four-layer substrate with double-sided components. Ten-layer molds are made separately, and the second layer is set as the GND layer. In the subsequent experiments, the GND layer is changed and the GND connection of the entire substrate is compared. Test tools: In data comparison, the data is tested by using an oscilloscope, multimeter, spectrum analyzer, and signal generator to obtain various test values; S2, GND integration setting and testing. The circuit board is first designed according to the independent way of each GND. Then, on this basis, the independent GNDs of the second layer are integrated into a whole, and the connection is ensured to be firm and the conductivity is good. The circuit board is powered on and the experimental values ​​are recorded. S3, GND separation setting and testing, separate the GND of different modules on the integrated substrate so that each module has an independent ground connection, repeat the power-on test operation in S2, and record the experimental data to compare the test results; S4. Performance difference analysis: Through power supply stability analysis, compare the measured data of power supply node voltage fluctuation in the two cases of GND integration and separation. Through signal integrity analysis, observe the waveform parameters of the signal during transmission. Through noise level analysis, compare the noise power spectrum density under the two grounding methods. Finally, through comprehensive evaluation, based on the above analysis results of power supply stability, signal integrity and noise level, comprehensively consider the actual application needs and performance requirements of the circuit board, and judge whether GND integration or separation is more suitable for the circuit board.

2. A simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to claim 1, characterized in that: The experimental substrate should include at least two modules with different functions and interrelated with each other, such as a digital signal processing module, an analog signal amplification module, and a power management module.

3. A simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to claim 1, characterized in that: When connecting the GND layer, different colors of solder resist are selected to facilitate the distinction of substrates with different GND connection methods.

4. A simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to claim 1, characterized in that: The test tool oscilloscope has sufficient bandwidth and sampling rate to accurately measure the time domain waveforms of various signals on the circuit board. An oscilloscope with a bandwidth of 3-5 times or more of the operating frequency of the circuit board is selected to ensure that the rapidly changing part of the signal can be clearly captured. The bandwidth is defined to be between 100MHz-500MHz.

5. A simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to claim 1, characterized in that: The frequency range of the test tool spectrum analyzer should cover the entire frequency band of the circuit board, and have sufficient resolution bandwidth RBW and video bandwidth VBW setting flexibility to accurately measure the signal strength and noise level at different frequencies, wherein the RBW can be set within the range of 1kHz-100kHz, and the VBW can be appropriately adjusted as needed.

6. A simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to claim 1, characterized in that: The multimeter, a testing tool, has the functions of measuring DC voltage, DC current, AC voltage and resistance. A multimeter with an accuracy of more than ±(0.5%+digit) is selected to ensure the accuracy of the measurement results.

7. A simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to claim 1, characterized in that: The GND integration setting and test measures the 5V output of the power module, and the power supply voltage fluctuation peak is 50mV. An oscilloscope is used to observe the waveforms of the audio amplifier input signal and output signal, and it is found that the signal distortion is small. The total harmonic distortion is calculated to be 0.5%. A spectrum analyzer is used to measure the noise level in the audio frequency band of 20Hz-100kHz, and the average noise power spectral density within the audio signal bandwidth is -60dBm / Hz.

8. A simple method for judging the performance difference of GND integration and separation of different modules in a circuit board according to claim 1, characterized in that: The GND separation setting and test is to separate the GND of each module and repeat the test, the power supply voltage fluctuation peak becomes 80mV, the THD of the audio amplifier becomes 0.8%, and the average noise power spectrum density in the audio frequency band is -55dBm / Hz.

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