Yukihiro Fukumoto

A simple method for measuring the relative permittivity of printed circuit board materials

This paper presents a simple method to measure the relative permittivity of glass-epoxy printed circuit boards (PCBs). In this method, the relative permittivity as a function of frequency is measured using an actual PCB. In order to estimate the relative permittivity, the reflection coefficient is measured with a network analyzer. The relative permittivity is calculated by observing the frequencies of the resonant cavity modes. We show that the relative permittivity of an FR-4 sample decreases from 4.3 to 4.2 at frequencies from 300 MHz to 2 GHz.

Power current model of LSI and parameter identification for EMI simulation of digital PCBs

A power current model of LSIs for EMI simulation of digital printed circuit boards, and a parameter identification method based on the model are presented. The model consists of equivalent internal impedance and an equivalent internal current source. The equivalent internal impedance is obtained by measuring the impedance between the power and ground terminal of an LSI by means of an impedance analyzer, and an equivalent internal source is obtained from the measured current through the power terminal under the conditions of known external impedance. Furthermore, it is shown that simulation results generated using this model have good agreement with the results of measurements made under a range of external impedances.

A design method of decoupling circuits for a digital PCB to reduce high frequency current on power and ground planes

This paper describes a design technique of decoupling circuits that can reduce high frequency current rushing into the power/ground planes of a digital PCB. In this technique, the IC is modeled as a current source of high frequency, and a parameter that represents the effect of the high frequency current reduction is derived. Then, by using the parameter, a design procedure to obtain the optimal bypass capacitor and the decoupling inductor is shown. Furthermore, validity of this modeling is shown by experimental study.

Radiated emission analysis of power bus noise by using a power current model of an LSI

In this paper, a power current model of an LSI was used for analysis of radiated emissions. The simulated radiation noise was compared with measurements by using an evaluation module that emulates an LSI. The simulation results showed good agreement with the measurement results. The effects of adding an internal decoupling capacitance and/or internal decoupling inductance to an LSI were also evaluated.

Key Challenges for Internet of Things in Consumer Electronics Industry

The key concept of IoT has the potential to be both a benefit and a threat not only to the ICT industry but also to the consumer electronics and device industries. Panasonic has high expectations for the IoT business and has already started providing value to individuals who live in smart homes. From a business viewpoint, we can simply describe “IoT” as ICT technologies that expanded from the computer to the non-computer world. However, there remain various technological issues to realize a genuine IoT world. This lecture introduces IoT business activities in the consumer electronics industry, and is followed by a discussion of the technological challenges for IoT both in the software and hardware layers.

Power decoupling circuit for modeling and measurement of EMC characteristics of IC/LSI

A circuit configuration is proposed which decouples an IC from the peripheral power source circuit. Merit is extended both on the standard measurement of the the EMI driving power and also on the low EMI circuit design of printed circuit boards. The two-stage decoupling circuit is found effective. These discussions are now conducted on a lumped circuit base, which should be further extended to distributed-parameter systems because the electromagnetic system is intrinsically distributed and the limit of the upper frequency to be considered is actually open referring to actual electronics applications.