TWI446199B - Method and system for analyzing temperature rise of printed circuit board - Google Patents

Description

Printed circuit board temperature rise analysis system and method

The invention relates to a printed circuit board temperature rise analysis system and method.

With the continuous development and advancement of electronic technology, the functions integrated in electronic products will be more and more. As the design trend of electronic products tends to be light and thin, the design of printed circuit boards in electronic products will become thinner and lighter. As a result, the power density in the printed circuit board will continue to increase. As the power density of printed circuit boards increases, the temperature generated by electronic products will become higher and higher, and too high temperatures will reduce the service life of electronic products. Therefore, electronic products are used during design. Estimating the amount of heat generated during the process is very important.

In view of the above, it is necessary to provide a temperature rise analysis system and method for a printed circuit board, which can calculate the temperature rise value of a local area of the printed circuit board during the initial development of the printed circuit board, and calculate the entire time when the printed circuit board design is completed. The temperature profile of the printed circuit board.

The printed circuit board temperature rise analysis system comprises: a selection module for selecting whether the system is to analyze the temperature rise value of the outer copper foil of the printed circuit board or the temperature rise value of the inner copper foil; and setting the module for setting printing The copper foil thickness of the circuit board, the wiring width of the power supply layer, and the current value flowing through the electronic components in the printed circuit board; the temperature rise formula determining module for setting the outer copper foil or the inner copper foil according to the selected printed circuit board and setting The thickness of the copper foil is determined from the database by a suitable temperature rise calculation formula; the calculation module is used for the thickness of the copper foil, the wiring width of the power supply layer, the current value flowing through the electronic component, and the determined temperature according to the above setting. The liter calculation formula calculates the local temperature rise value around the electronic component.

The method for analyzing the temperature rise of the printed circuit board includes: selecting a temperature rise value of the outer copper foil of the printed circuit board or the inner copper foil; setting the thickness of the copper foil of the printed circuit board, the wiring width of the power layer, and flowing through the electronic component The current value; the temperature rise calculation formula for calculating the temperature rise value according to the selected outer copper foil or inner copper foil and the thickness of the set copper foil; according to the thickness of the copper foil of the printed circuit board, the wiring width of the power supply layer, and the flow rate The current value of the electronic component and the temperature rise calculation formula calculate a local region temperature rise value around the electronic component.

Compared with the prior art, the printed circuit board temperature rise analysis system and method calculate the temperature rise value of the printed circuit board during the initial development of the printed circuit board, and calculate the entire printed circuit board when the printed circuit board design is completed. The temperature distribution makes it easy to analyze whether there is excessive temperature rise in the printed circuit board, thereby effectively avoiding the decrease in the service life of the electronic product caused by insufficient consideration of the temperature rise of the printed circuit board during design.

The object of the present invention is to estimate the local temperature rise value generated when the printed circuit board is operated when designing the printed circuit board, and calculate the temperature distribution diagram of the printed circuit board when the design is completed, by using the temperature The distribution map is analyzed to reveal areas of excessive temperature in the printed circuit board, and the design of the area is modified. The theoretical basis of the present invention will first be described below.

In the present invention, the temperature rise calculation formula is: I=a*S ^α *(ΔT) ^β , where I is the current value flowing through each electronic component in the printed circuit board, and S is the cross-sectional area of the printed circuit board copper foil. The cross-sectional area is the product of the thickness of the copper foil of the printed circuit board and the wiring width of the power supply layer, and ΔT refers to the temperature rise value of the printed circuit board during operation, wherein the coefficients a, α, and β are the thickness of the copper foil of the printed circuit board and Determined by the outer copper foil or inner copper foil of the printed circuit board. It can be seen from the temperature rise calculation formula that as long as any three parameter values of the thickness of the copper foil of the printed circuit board, the wiring width of the power supply layer, the current value flowing through the copper foil, and the temperature rise value are known, Calculating the fourth parameter value, in the preferred embodiment of the present invention, the method for calculating the temperature rise value and the wiring width of the power layer at the beginning of the design of the printed circuit board and calculating the temperature distribution map when the printed circuit board design is completed is explained. .

As shown in Figure 1, it is a temperature rise graph of a printed circuit board. The outer copper foil or the inner copper foil of the printed circuit board having different copper foil thicknesses have different temperature rise curves. 1 is a temperature rise graph of a copper foil of a printed circuit board having a copper foil thickness of 2.4 mil. By analyzing and calculating the temperature rise curve in FIG. 1, a printed circuit board suitable for a copper foil thickness of 2.4 MIL can be obtained. The values of a, α and β coefficients in the formula for calculating the temperature rise of the outer copper foil. By analyzing a number of temperature rise curves similar to those of Figure 1, for example, the temperature rise curve of the inner layer of the printed circuit board or the outer layer of copper foil with a copper foil thickness of 3.6 mil can be analyzed to obtain different copper foil thicknesses. The coefficient values of a, α and β in the formula for calculating the temperature rise of the outer copper foil or the inner copper foil of the printed circuit board. In the present invention, the coefficient values of a, α and β in the temperature rise calculation formula of the outer layer copper foil or the inner layer copper foil of the printed circuit board suitable for different copper foil thicknesses are stored in a database, which is also suitable for different copper foils. The temperature rise calculation formula of the outer layer copper foil or the inner layer copper foil of the printed circuit board of thickness is stored in the database, and only the thickness of the copper foil of the printed circuit board, the wiring width of the power layer, and the current value are set in the subsequent calculation of the temperature rise value. And selecting the outer copper foil or the inner copper foil of the printed circuit board, and determining the thickness of the copper foil suitable for the setting according to the thickness of the copper foil provided and the outer copper foil or the inner copper foil of the selected printed circuit board. The temperature rise value is calculated by calculating the temperature rise of the outer copper foil or the inner copper foil of the circuit board.

As shown in FIG. 2, it is an architectural diagram of the temperature rise analysis system of the printed circuit board of the present invention. The printed circuit board temperature rise analysis system 11 runs in the computer 1, and the computer 1 further includes a database 12 in which the temperature of the outer copper foil or the inner copper foil based on the thickness of the plurality of printed circuit board copper foils is stored. The calculation formula, the database 12 is further configured to store a current density distribution map of the printed circuit board when the printed circuit board design is completed, and the current density distribution map is formed by a specific printed circuit board current analysis tool when the printed circuit board is designed. The current of the printed circuit board is obtained by analog analysis.

As shown in FIG. 3, it is a functional module diagram of the temperature rise analysis system of the printed circuit board of the present invention. The printed circuit board temperature rise analysis system 11 includes a selection module 110, a setting module 111, a temperature rise formula determining module 112, a computing module 113, and an import module 114.

The selection module 110 is configured to select whether the temperature rise value of the outer copper foil of the printed circuit board or the inner copper foil is to be calculated.

The setting module 111 is configured to set a copper foil thickness of the printed circuit board, a wiring width of the power supply layer, and a current value flowing through the electronic component in the printed circuit board to calculate a local temperature rise value around the electronic component.

The setting module 111 is further configured to set a copper foil thickness of the printed circuit board, a current value flowing through the electronic component in the printed circuit board, and a maximum local temperature rise value allowed by the electronic component to calculate how much power layer wiring width is required. The local temperature rise around the electronic component is made to meet the design requirements.

The temperature rise formula determining module 112 is configured to determine a temperature rise formula suitable for the condition from the database 12 according to the outer copper foil or the inner copper foil of the selected printed circuit board and the thickness of the disposed copper foil. .

The calculation module 113 is configured to calculate a local region temperature rise value around the electronic component according to the copper foil thickness, the current value flowing through the electronic component, the wiring width of the power supply layer, and the determined temperature rise calculation formula.

The calculation module 113 is further configured to calculate the design of the electronic component according to the copper foil thickness, the current value flowing through the electronic component, the highest local temperature rise allowed around the electronic component, and the determined temperature rise calculation formula. The required wiring width of the power plane.

The setting module 111 is further configured to set an ambient temperature of the printed circuit board and a thickness of the copper foil when the temperature distribution map of the printed circuit board needs to be calculated when the printed circuit board is designed. Since the temperature distribution map of the printed circuit board is needed here, the temperature rise calculation formula calculates the temperature rise value of the printed circuit board, and adds the temperature rise value to the ambient temperature to obtain the temperature of the printed circuit board. The value, so that the temperature profile of the printed circuit board can be further calculated.

The lead-in module 114 is used to introduce a current density profile of the printed circuit board when the temperature distribution of the printed circuit board needs to be calculated when the printed circuit board is designed.

The current density refers to a ratio of a current value flowing through a printed circuit board copper foil to a cross-sectional area of a printed circuit board copper foil, and the current density distribution map is designed by the specific printed circuit board current analysis tool on the printed circuit board. The printed circuit board is subjected to simulation analysis and stored in the database 12, and the current density distribution map has a specific format, and the current density value of each point in the figure is a fixed cross-sectional area current density. Value, so the temperature profile of the printed circuit board can be calculated by simply setting the copper foil thickness of the printed circuit board and selecting the outer copper foil or the inner copper foil to determine the temperature rise calculation formula.

The calculation module 113 is further configured to calculate a temperature distribution map of the printed circuit board according to an ambient temperature of the installed printed circuit board, a current density distribution map of the introduced printed circuit board, and the temperature rise calculation formula.

As shown in FIG. 4, it is a flow chart of the temperature rise analysis method of the printed circuit board of the present invention.

In step S01, the selection module 110 selects whether the temperature rise value of the outer copper foil of the printed circuit board or the inner copper foil is to be calculated.

In step S02, the setting module 111 sets the thickness of the copper foil of the printed circuit board, the wiring width of the power supply layer, and the current value flowing through the electronic component.

In step S03, the temperature rise formula determining module 112 determines a temperature rise calculation formula suitable for the condition from the database 12 according to the selected outer copper foil or inner copper foil and the thickness of the provided copper foil.

Step S04, the calculation module 113 calculates the local area temperature around the electronic component according to the thickness of the copper foil of the printed circuit board, the wiring width of the power layer, the current value flowing through the electronic component, and the temperature rise calculation formula. appreciation.

In this embodiment, it is also possible to calculate the wiring width of the power supply layer by setting the copper foil thickness of the printed circuit board, the current value flowing through the electronic component in the printed circuit board, and the highest local temperature rise value allowed around the electronic component. The temperature rise of the local area around the electronic component will meet the design requirements.

After the printed circuit board design is completed, the present invention analyzes the temperature profile of the printed circuit board to analyze whether there is an excessive temperature in the printed circuit board to modify the design. As shown in FIG. 5, it is a flow chart for calculating a temperature distribution map of a printed circuit board in the temperature rise analysis method of the printed circuit board of the present invention.

In step S10, the selection module 110 selects whether the temperature profile of the outer copper foil of the printed circuit board or the inner copper foil needs to be calculated.

Step S11, when the printed circuit board design is completed, the introduction module 114 introduces a current density distribution map of the printed circuit board.

In step S12, the setting module 111 sets the ambient temperature at which the printed circuit board operates and the copper foil thickness of the printed circuit board.

Step S13, the temperature rise formula determining module 112 is configured to determine a temperature required to calculate a temperature profile from the database 12 according to the copper foil thickness of the printed circuit board and the selected outer copper foil or inner copper foil. l Calculate the formula.

In step S14, the calculation module 113 calculates a temperature distribution map of the printed circuit board according to the current density distribution map, the ambient temperature, and the temperature rise calculation formula.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and equivalent modifications or variations made by those skilled in the art in light of the spirit of the present invention are It should be covered by the following patent application.

1‧‧‧ computer

11‧‧‧Printed circuit board temperature rise analysis system

12‧‧‧Database

110‧‧‧Selection module

111‧‧‧Setup module

112‧‧‧ Temperature rise formula determination module

113‧‧‧Computation Module

114‧‧‧Import module

S01‧‧‧Select whether to calculate the temperature rise of the outer copper foil or the inner copper foil

S02‧‧‧Set wiring width, copper foil thickness, and current flowing through electronic components

S03‧‧‧ Determine the formula for calculating the temperature rise based on the thickness of the outer copper foil or inner copper foil and the thickness of the copper foil

S04‧‧‧ Calculate the temperature rise of the local area around the electronic component according to the setting and the temperature rise calculation formula

S10‧‧‧Select whether to calculate the temperature profile of the outer copper foil or the inner copper foil of the printed circuit board

S11‧‧‧ Current density distribution map imported into the printed circuit board

S12‧‧‧Set the ambient temperature and copper foil thickness of the printed circuit board

S13‧‧‧ Determine the temperature rise calculation formula required to calculate the temperature profile

S14‧‧‧ Calculate the temperature distribution of the printed circuit board based on the current density distribution map, ambient temperature and temperature rise formula

Figure 1 is a graph of the temperature rise of a printed circuit board.

2 is a structural diagram of a temperature rise analysis system for a printed circuit board of the present invention.

3 is a functional block diagram of a temperature rise analysis system for a printed circuit board of the present invention.

4 is a flow chart of a method for analyzing temperature rise of a printed circuit board according to the present invention.

FIG. 5 is a flow chart for calculating a temperature distribution map of a printed circuit board in the temperature rise analysis method of the printed circuit board of the present invention.

S01‧‧‧Select whether to calculate the temperature rise of the outer copper foil or the inner copper foil

S02‧‧‧Set wiring width, copper foil thickness, and current flowing through electronic components

S03‧‧‧ Determine the formula for calculating the temperature rise based on the thickness of the outer copper foil or inner copper foil and the thickness of the copper foil

S04‧‧‧ Calculate the temperature rise of the local area around the electronic component according to the setting and the temperature rise calculation formula

Claims (10)

A printed circuit board temperature rise analysis system is run in a computer. The computer library stores a temperature rise calculation formula of an outer layer copper foil and an inner layer copper foil based on a plurality of printed circuit board copper foil thicknesses, and the system includes:
Selecting a module for selecting whether the system is to analyze the temperature rise of the outer copper foil of the printed circuit board or the temperature rise of the inner copper foil;
a module for setting a copper foil thickness of the printed circuit board, a wiring width of the power supply layer, and a current value flowing through the electronic component in the printed circuit board;
a temperature rise formula determining module for determining a suitable temperature rise calculation formula from the database according to an outer copper foil or an inner copper foil of the selected printed circuit board and a set copper foil thickness; and a calculation module, The local region temperature rise value around the electronic component is calculated according to the copper foil thickness set by the above, the wiring width of the power supply layer, the current value flowing through the electronic component, and the determined temperature rise calculation formula. The printed circuit board temperature rise analysis system according to claim 1, wherein the setting module is further configured to set a thickness of a copper foil of the printed circuit board, a current value flowing through the electronic component in the printed circuit board, and a periphery of the electronic component. The highest local temperature rise value allowed; and the calculation module is further configured to calculate the thickness of the copper foil, the current value flowing through the electronic component, the highest local temperature rise allowed around the electronic component, and the determined temperature rise according to the above setting. The formula calculates the wiring width of the power plane required for the design of the electronic component. The printed circuit board temperature rise analysis system of claim 1, wherein the system further comprises:
Introducing a module for introducing a current density distribution map of the printed circuit board when the temperature distribution map of the printed circuit board is calculated after the printed circuit board design is completed;
The setting module is further configured to: when calculating a temperature distribution map of the printed circuit board after the printed circuit board design is completed, setting an ambient temperature of the printed circuit board and a thickness of the copper foil; and the calculating module is further configured to The introduced current density profile, the ambient temperature, and the temperature rise calculation formula calculate the temperature profile of the printed circuit board. The printed circuit board temperature rise analysis system of claim 3, wherein the current density profile is simulated by a specific printed circuit board current analysis tool when the printed circuit board is designed and completed. Draw and save in the computer. The temperature rise analysis system of the printed circuit board according to claim 1, wherein the temperature rise calculation formula is I=a*S ^α *(ΔT) ^β , wherein I refers to each electronic component flowing through the printed circuit board. The current value, S refers to the cross-sectional area of the printed circuit board copper foil, which is the product of the thickness of the copper foil of the printed circuit board and the wiring width of the power supply layer, and ΔT refers to the temperature rise value of the printed circuit board during operation, coefficient a , α and β are determined by the thickness of the copper foil of the printed circuit board and the outer copper foil or inner copper foil of the printed circuit board. A method for analyzing temperature rise of a printed circuit board is applied to a computer, wherein a database for calculating a temperature rise of an outer copper foil and an inner copper foil based on a plurality of copper foil thicknesses of the printed circuit board is stored in the database, the method comprising the following steps :
Choose whether to calculate the temperature rise of the outer copper foil of the printed circuit board or the inner copper foil;
Setting a copper foil thickness of the printed circuit board, a wiring width of the power supply layer, and a current value flowing through the electronic component;
Calculating a temperature rise calculation formula for calculating the temperature rise value according to the selected outer copper foil or inner copper foil and the thickness of the provided copper foil; and the thickness of the copper foil of the printed circuit board, the wiring width of the power supply layer, and the flow of the electronic component according to the set thickness The current value and the temperature rise calculation formula calculate a local region temperature rise value around the electronic component. The method for analyzing a temperature rise of a printed circuit board according to claim 6, wherein the method further comprises the step of calculating a width of the power layer wiring, wherein the step of calculating the width of the power layer wiring comprises:
Choose whether to calculate the wiring width of the outer copper foil of the printed circuit board or the power supply layer of the inner copper foil;
Setting a copper foil thickness of the printed circuit board, a current value flowing through the electronic component in the printed circuit board, and a maximum local temperature rise allowed around the electronic component;
The temperature rise calculation formula is determined according to the thickness of the set copper foil and the selected outer copper foil or inner copper foil; and the thickness of the copper foil, the current value flowing through the electronic component, and the highest local temperature rise allowed around the electronic component. And the determined temperature rise calculation formula calculates the wiring width of the power supply layer required for the design of the electronic component. The method for analyzing a temperature rise of a printed circuit board according to claim 6, wherein the method further comprises the step of calculating a temperature distribution map of the printed circuit board, wherein the step of calculating the temperature distribution map of the printed circuit board comprises:
The temperature distribution map of the outer copper foil of the printed circuit board or the inner copper foil is selected.
Introducing a current density profile of the printed circuit board;
Setting the ambient temperature of the printed circuit board and the thickness of the printed circuit board copper foil;
Calculate the temperature rise calculation formula required to calculate the temperature profile according to the thickness of the copper foil of the printed circuit board and the selected outer copper foil or inner copper foil; and calculate according to the current density distribution map, the ambient temperature and the temperature rise calculation formula The temperature profile of the printed circuit board. The method for analyzing a temperature rise of a printed circuit board according to claim 8, wherein the current density profile is simulated by a specific printed circuit board current or voltage analysis tool when the printed circuit board is designed. Analyzed and saved in the computer. The method for analyzing a temperature rise of a printed circuit board according to claim 6, wherein the temperature rise calculation formula is I=a*S ^α *(ΔT) ^β , wherein I refers to each electronic component flowing through the printed circuit board. The current value, S refers to the cross-sectional area of the printed circuit board copper foil, which is the product of the thickness of the copper foil of the printed circuit board and the wiring width of the power supply layer, and ΔT refers to the temperature rise value of the printed circuit board during operation, coefficient a , α and β are determined by the thickness of the copper foil of the printed circuit board and the outer copper foil or inner copper foil of the printed circuit board.