EMI Suppression Filters (EMC and Noise Suppression)Case: Improving the conversion efficiency of DC-DC converters

We just can’t seem to improve the conversion efficiency of our DC-DC converters. What is the quickest route to solving this problem?


“What are the hurdles that we must clear in order for us to create top-of-the-line low-power-consumption models?”

This case history concerns Company K, whose main strength lies in units that are to be incorporated into on-site terminals. Due to the increasing number of cases in which tablet-type terminals are used as different kinds of on-site terminals, the company was very serious about gathering information. The on-site issues didn’t just concern increasingly sophisticated functions. At those sites that were slow to establish optimum charging environments, the major concern was how long the batteries lasted.

What are the hurdles that we must clear in order for us to create top-of-the-line low-power-consumption models?

As information was being gathered, Company K was approached with a new project for developing tablet terminals for use in health care sites, and they were entrusted with the design of the main boards for these terminals. The selling point for these new tablet terminals was that they were to be the one of the best in low power consumption among competing products.

Because of this, since the circuits already designed by the company did not meet the required specifications, the company had to develop a new product, even though there was little time left to design it.

“At the heart of the problem is the conversion efficiency of the DC-DC converters. However, we can’t find the power inductors we need.”

When the company finally finished a prototype board, they began to evaluate it. However, even after many attempts, the board still failed to reach the target battery operation time, and the design team members scrambled to pin down the cause of the problem. The evaluations were repeated, and the company discovered that the low conversion efficiency rate of the DC-DC converter was to blame. They decided to study a variety of power inductors, a key component.

As a result of their efforts, the team found that the conversion efficiency changes when the power inductors are changed, and they realized that these components were definitely having an effect of some kind. However, the team was unable to identify which power inductors could achieve the highest conversion efficiency and meet the target specifications, and even after a lot of time passed, the company was still unable to select a power inductor.

Main points of the issues:

  1. The company could not use any of its existing circuits, and had to develop new circuits in a short period of time.
  2. The company’s prototype was unable to meet the target battery operation time, which was the selling point of the company’s new product.
  3. Although the company did manage to identify the cause of the problem encountered, it could not find ideal power inductors.
How can we solve this problem?