Printed Circuit Design & Fab Online Magazine - Features

Features

Understanding reflections caused by transmission line characteristic impedance and termination impedance mismatch.

Analysis of “digital interconnects” is the analog problem in frequency domain where interconnects are simulated as transmission lines defined by characteristic impedance and propagation constant. Digital signals in interconnects are sequences of amplitude-modulated pulses that transmit bits between components. The “digital interconnect” analysis problem is technically an analog problem of pulse propagation modeling in time-domain.

Not leaving enough clearance is a design oversight that can have costly consequences.

As PCB designers, fabricators and assemblers, we wear a lot of hats at Rush PCB. We're always working to design and build PCBAs that are the best they can be. But sometimes we are consigned product to assemble that wasn't designed by our team, and every so often we get boards that tempt us to say, "The designer clearly wasn't thinking about how we are going to build this!"

Taking the confusion out of determining appropriate data collection parameters.

In 1924, Dr. Walter Shewhart was working at Bell Telephone Laboratories. On May 16 of that year, Dr. Shewhart wrote a memorandum in which he presented and proposed the process control chart to his superiors. Bell Telephone Laboratories believed this memorandum gave it a competitive advantage and held this paper internally. In 1931, Dr. Shewhart published his book Economic Control of Quality of Manufactured Product. In this book, Dr. Shewhart explained in detail the fundamental concepts and benefits of statistical process control. This seminal work laid the foundation for the modern quality control discipline, and the process control chart became the bedrock of quality control systems.

A design can look good on paper, but has it been vetted for manufacturing?

Printed circuit board assembly: What comes to mind when you hear, read, or think that term? What does or should this mean to a printed circuit board designer or a printed circuit engineer? Is it an afterthought within the overall process of designing and manufacturing your product in the rush to get your product to market the fastest while trying to minimize your cost?

A comparison of energy, water and chemical use for two common processes.

“We will make decisions based on sustainability, Lenora.” I heard the words clearly. I understood the tone in his voice and the impact it would mean for the industry moving forward. Interestingly, it was not the only time I would hear that same statement within a few weeks.

Thermal interface materials provide much-needed heat relief for electronic assemblies.

Overheating is the number one cause of electronic component failure and requires aggressive thermal management strategies. That’s why thermal interface materials (TIMs) have become ubiquitous in today’s electronic assemblies, working to dissipate heat from heat-sensitive components, improve device reliability, and prevent premature failure.

The two main categories of thermal interface materials are TIM1 and TIM2. Used together, they create a comprehensive thermal management solution at both the chip and semiconductor package level.