Here you'll find insights into PCB design, tech trends, assembly issues, and trending topics
in the general news media as they relate to printed circuit board technology.
As experts in the manufacture and assembly of printed circuit boards, we work to make our blog a helpful resource on PCB topics and the industries that we work with, including automotive, consumer electronics, aerospace and many more.
In the design of power circuit, electromagnetic interference is one of the key factors affecting product performance. At present, there are many ways to solve the problem of EMI for engineers. Generally, methods for suppressing EMI include: EMI suppression coating, EMI simulation. Design and selection of suitable EMI suppression parts. This article will start with the PCB, and introduce the role and design skills of PCB layered stacking in controlling EMI radiation.
Conducting printed circuit board (PCB) design refers to the production of circuit boards at the lowest possible cost by designing schematic drawings and wiring layout. In the past, this usually required expensive tools, but now, with the availability of free high-performance software tools such as DesignSpark PCBs and design models, the speed of board designers has been greatly accelerated.
In high speed designs, the characteristic impedance of the controllable impedance plates and lines is one of the most important and common problems. First, let's look at the definition of a transmission line: a transmission line consists of two conductors of a certain length, one for transmitting signals and the other for receiving signals (remember that the "loop" replaces the concept of "ground"). In a multi-layer board, each line is part of a transmission line, and an adjacent reference plane can be used as a second line or loop. The key to a line becoming a "good performance" transmission line is to keep its characteristic impedance constant throughout the line.
In high-speed designs, the matching of impedance is related to the quality of the signal. The technique of impedance matching can be said to be rich and varied, but how to make a reasonable application in a specific system requires measuring various factors. For example, in our design in the system, many of them use the serial matching of the source segment. Why do you need to match and what kind of matching is used? For example, the majority of the differential matching uses the matching of the terminal; the clock uses the source segment matching.
There are many English abbreviations in the field of electrical interference.
The PCB board is divided into many layers. What are the techniques for the high four-layer routing? Let me introduce you to the following.
As memory designs become more complex and compact, and data rates are increasing, the use of BGA probes to detect DDR DRAM is becoming more popular and has become a requirement. The DDR3 and DDR4 data rates have increased from 800 MT/s to approximately 3200 MT/s. Memory system designers are concerned about whether current BGA probe designs can meet high bandwidth requirements for optimal signal fidelity. Signal fidelity is important for accurate DDR conformance measurements based on JEDEC specifications. In addition, the memory designer needs to perform signal integrity measurements to complete the margin test. Moreover, the margin after eliminating the DDR BGA probe detection effect can be used to design components with lower tolerances. This article describes a new probe calibration method for scalable DDR BGA probe bandwidth to increase the margin of signal integrity testing and minimize errors caused by DDR BGA probes.
When a square wave of a signal is propelled forward by a high-level positive pressure signal in the signal line of the transmission line assembly, the theoretical reference layer (such as the ground layer) is theoretically necessary. The negative pressure signal induced by the electric field is accompanied by the forward path (equal to the return path of the positive pressure signal reverse path), so that the integral loop system can be completed. If the "signal" advances its flight time for a short period of time, it can be imagined that it suffers from the instantaneous impedance value (Instantanious Impedance) from the signal line, the dielectric layer and the reference layer. This is called "Characteristic impedance."
The abstract and complicated digital high-speed logic principle, how to transmit the square wave signal in the transmission line, and how to ensure its signal integrity (Signal Integrity), reduce the noise of its noise (Noise) and other professional expressions, if simple The example of life is explained, but instead of moving a bunch of mathematical formulas and difficult physics language, it is the inspiration and benefit for novices or interlocutors.
How to improve anti-interference ability and electromagnetic compatibility when developing electronic products with processors?
5-7 Measures taken to increase the system's ability of it.
1-4 Measures taken to increase the system's ability of it.
For the impact of the transmission line problem, we will talk about the ways to control these effects from the following aspects.
Based on the transmission line model, in summary, the transmission line will have the following effects on the overall circuit design.
High-speed circuit design is a very complex design process. There are several factors that need to be considered when designing a high speed circuit. These factors are sometimes opposite each other. Such as the high-speed device layout when the position is close, although the delay can be reduced, but crosstalk and significant thermal effects may occur. Therefore, in the design, we must weigh the various factors and make a comprehensive compromise; not only meet the design requirements, but also reduce the design complexity. The adoption of high-speed PCB design means the controllability of the design process. Only controllable is reliable.
In design, layout is an important part. The quality of the layout results will directly affect the effect of the wiring, so it can be considered that a reasonable layout is the first step in the success of PCB design.
In the PCB design, wiring is an important step to complete the product design. It can be said that the previous preparation work is done for it. In the whole PCB, the wiring design process is the highest, the trick is the finest, and the workload is the largest. The PCB wiring has single-sided wiring, double-sided wiring, and multilayer wiring. There are two ways to route: automatic routing and interactive wiring. Before automatic routing, you can use interactive pre-wired lines that require more stringent requirements. The edges of the input and output should avoid adjacent parallel to avoid reflection interference. If necessary, ground wire should be isolated. The wiring of two adjacent layers should be perpendicular to each other, and parasitic coupling is easy to occur in parallel.
Layer setting and power ground segmentation requirements; Power module requirements