Method for obtaining dielectric constant of PCB materials
A technology of dielectric constant and dielectric layer, applied in the direction of measuring electrical variables, measuring resistance/reactance/impedance, measuring devices, etc.
Inactive Publication Date: 2014-07-09
GUANGZHOU FASTPRINT CIRCUIT TECH +2
View PDF4 Cites 12 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
When conventional printed circuit boards are used for high-speed and high-frequency signals, the impedance matching problems that do not occur in low-frequency circuits surface
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0041] Embodiments of the present invention are described in detail below:
[0042] Such as figure 1 As shown, it is a schematic diagram of an impedance test pattern with a microstrip line according to an embodiment of the present invention. Obtain the method for PCB material dielectric constant of the present invention, comprise the steps:
[0043] Etch the impedance test pattern on the PCB substrate, wherein, the impedance test pattern includes the pad 12 electrically connected to the end of the microstrip line 11 and the microstrip line 11, and the pad 12 has a test hole 13, through which the impedance test pattern The measured impedance value Z is more accurate.
[0044] Obtain the impedance value Z of the microstrip line 11, and obtain the line width W of the microstrip line 11, the thickness T of the copper foil of the microstrip line 11, and the thickness H of the dielectric layer 10 connected to the impedance test pattern; The impedance value Z of the microstrip lin...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| Length | aaaaa | aaaaa |
| Aperture | aaaaa | aaaaa |
Login to View More
Abstract
The invention discloses a method for obtaining the dielectric constant of PCB materials. The method comprises the steps that an impedance test pattern is etched on a PCB substrate, wherein the impedance test pattern comprises a microstrip line and a bonding pad which is electrically connected with the end of the microstrip line, and the bonding pad is provided with a test hole; the impedance value Z of the microstrip line is obtained, and the width W of the microstrip line, the thickness T of copper foil of the microstrip line and the thickness H of a dielectric layer connected with the impedance test pattern are obtained; the parameters are substituted into the formula , and then the value of the dielectric constant DK of a dielectric layer material which needs testing can be obtained. According to the method, the impedance test pattern is etched on the PCB substrate, the impedance test pattern is divided into a microstrip line impedance test pattern part and a differential line impedance test pattern part, impedance of the microstrip line or a differential line is obtained through the impedance test pattern and then substituted into the formula, and therefore the dielectric constant of the dielectric layer connected with the impedance test pattern can be obtained.
Description
technical field [0001] The invention relates to the technical field of printed circuit boards, in particular to a method for obtaining the dielectric constant of PCB materials. Background technique [0002] With the advancement of science and technology, the integration level of integrated circuits is improved and the working speed of circuits is getting faster and faster, and the frequency and speed of signal transmission are getting higher and higher. The wires on the printed board must act as high-performance transmission lines, and the output terminal The signal is completely and accurately transmitted to the input of the receiving device. When conventional printed circuit boards are used for high-speed and high-frequency signals, the impedance matching problems that do not appear in low-frequency circuits surface. Due to the advancement of technology, printed circuit boards are not only a simple interconnection tool, the control value of characteristic impedance is one...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More IPC IPC(8): G01R27/26
Inventor 刘洋刘攀曾志军
Owner GUANGZHOU FASTPRINT CIRCUIT TECH