Tencent Digital (Shawn) Apple's macOS is essentially an open source operating system, which may sound a bit strange, but it is indeed the case. Apple is one of the world's most profitable technology companies, but the operating system core of its Mac series is completely free software. These open source components are called Darwin, which forms the main part of the macOS kernel, Linux BSD partitions, and other drivers. For this reason, Apple will provide these open source software downloads since OS X 10.0. And now, Darwin for macOS 10.12 Sierra is also available for free download. Darwin is not Apple's only open source software. Through the cooperation with Oracle's OpenJDK project, Apple also provided source code download for Java for Mac. In addition, Apple's latest programming language, Swift, also has an open source version to attract students and other developers who cannot reach the language. This series of actions by Apple shows that this company is very clear about its competition in the application development and PC market. Other mainstream technology companies also attach great importance to open source projects. Take Microsoft as an example. The company has launched several initiatives in the past few years to reach a more intimate relationship with the open source community. Recently, Microsoft joined the Linux Foundation as a senior member, added support for Bash in Windows 10, and introduced the Linux version of SQL Server. It is clear that for-profit technology companies have become increasingly aware of the importance of free and open source software for maintaining profitability. Wonderful video recommendation: Source: DigitalTrends Control impedance PCB Impedance Control Board,Impedance Controlled PCB,Gold Fingers PCB,Impedance Control PCB Storm Circuit Technology Ltd , https://www.stormpcb.com
Many customers asked us what information we need for impedence control PCB.Here,there are two types for PCB manufacturer,a is single impedance ,just one trace ,two holes .and b is differential impedance,it always go with 1 pair (two trace with same width and space). For single impedance,you just tell us the trace width one which layer and what value you require .For differential impedance,trace width/space,layers and value. Our experience engineers will calculate following your instruction with Polar software.We may change trace width/space or stackup ,but please do not worry, if any changes,we will send you to approve before proceeding. Generally,the tolerance is 10%,and more accurate is 8% .All impedance boards ,we will test here and report.