The demand for small, fast wireless electronic products is on the rise
Embedded system noise reduction, from the early stages of design
Take this into account and shorten power wiring and utilize capacitors.


High-performance wireless electronic products are being widely used not only in homes but also in various industries. Small terminals now perform some tasks that were previously handled by large central devices, and more data is transmitted and received wirelessly with low latency rather than via wires.

The market is demanding smaller size, better performance, faster speeds, and lower power consumption from electronic products. So, what are the most important factors that engineers designing electronic products should consider?

It is the power supply. Only when supported by a stable power supply can a designed product perform at its best. There are various factors that affect the power supply. In particular, the causes of EMI amount to approximately 500 million. It is very difficult to control all of this within a limited time.

We asked Park Kyung-jin, CEO of Creca, who will be giving a special lecture titled "Design Methods for Power Stabilization in Embedded Systems" at the " 2020 Mouser Power Seminar " on the upcoming Wednesday, the 21st, what mindset relevant engineers should have for effective power design and stable power management.


Q. Please give a brief self-introduction and an introduction to your company.
A. Hello. I am Park Kyung-jin, CEO of Creka Co., Ltd., a company engaged in radar development, sales, and technical consulting. I am currently conducting hardware-related training at the e4ds Lifelong Education Center.


Q. What are some of the recent issues in the field of embedded system design?
A. The trend in embedded systems is miniaturization and low power consumption, with new technologies such as high frequency and high-speed digital transmission being applied. Consequently, the factors that engineers must consider during the design, manufacturing, and debugging processes are increasing. Furthermore, the rising cost of measurement equipment has placed a significant burden on companies.


Q. When designing power supplies for embedded systems, what should engineers prioritize to ensure the smooth operation of the entire system?
A. Fundamentally, you must consider the overall power block. You need to identify the incoming input voltage—for example, 5V, 3.3V, or 2.5V—classify and organize it into analog and digital, and then draw up a rough ground separation plan. Additionally, you must review whether the wiring lengths and the number of capacitors are sufficient. Subsequently, you must consider the placement of power components and functional ICs during the PCB artwork phase. This is to prevent noise-generating factors in advance.


Q. What are the main causes of noise in power signals? And what methods are available to identify the points where that noise occurs?
A. Ripple is likely the first thing that comes to mind as a major cause of noise in power supplies. In addition, one can consider spark-like voltage and current. Theoretically, these factors are caused by parasitic resistive and inductive components. Generally, the longer the wiring in a power supply, the greater the possibility of external noise entering. This can be fully verified using an oscilloscope.


Q. Capacitors appear to be widely used in PCB Power Distribution Network (PDN) design. What are the criteria for selecting suitable capacitors?
A. This requires examination from various angles. PDN is fundamentally a design method worth utilizing. PDN serves as the standard for selecting capacitor values. Referencing this can lead to a good circuit design. What needs a little more thought here is the length of the power wiring. If the length is not very long, the number of capacitors can be fewer than the theoretical amount.


Q. If we continue to manufacture products to verify how much noise has been reduced, it will cause problems in terms of cost and time. I would like to know about the simulation method that overcomes this.
A. While utilizing simulations would be ideal, it is realistically difficult to implement due to the high cost of the software. Noise reduction design strategies must begin with understanding the theoretical aspects and closely observing and utilizing actual PCB guidelines.


Q. Lastly, do you have any advice for power design engineers?
A. I would like to emphasize that power design should not be solely focused on the power supply. A good power design will result from understanding the functional systems receiving power, viewing the overall system, and considering whether there will be any power-related issues in operation scenarios. Thank you.