Naoya Tamaki

High frequency magnetic near field measurement on LSI chip using planar multi-layer shielded loop coil

Magnetic near-field measurements of circuitry are gathering increasing interest as an effective technique for detecting noise emission current sources. Against this background, we developed planar thick-film multi-layer shielded loop coils with loop apertures of 20 /spl mu/m x 1000 /spl mu/m and 600 /spl mu/m x 600 /spl mu/m. The shielded-loop structures main feature is the cancellation of voltage induced by the electric field. A 60-/spl mu/m wide microstrip line was used as the device under test (DUT). In a spatial resolution test conducted at 1GHz, we obtained optimum spatial resolution of 90 /spl mu/m at the 6 dB degrading point for a rectangular coil with a 20/spl mu/m x 1000 /spl mu/m aperture. This resolution level is 2.8 times better than that we obtained with our previous product comprising a low temperature co-fired ceramic (LTCC) board, because with the new coils we were able to successfully reduce the mean distance between the loop and the DUT. In measuring nonuniform magnetic field distribution near the 1.58 mm-wide microstrip line and the internal chip of a large-scale integrated (LSI) circuit, we found the new model could measure a finer distribution than our previous probe.

Wide band wearable antenna for DTV reception

This paper describes the wideband wearable T-shape monopole antenna with parasitic elements and the wearable slot antenna with an arrow head for receiving the digital television broadcasting wave from 470 MHz to 770 MHz in Japan. These proposed wearable antennas achieved the good wideband performance in the condition that these antennas are in the free space. As a next stage, the VSWR and radiation pattern of both antennas are on the jacket worn by a human body have to be measured.

A multilayer board-type magnetic field probe with high spatial resolution and RF current estimation method for ICs

The authors describe how NEC and NEC Glass Components Co. Ltd. developed a magnetic field probe with high spatial resolution enabling the measurement of magnetic fields near IC packages and dense-printed circuit boards (PCBs) so that RF currents can be estimated. The design of the magnetic field probe is based on a multilayer board, and achieves spatial resolutions at least 1.8 times those of previous probes, as well as a reduction by up to 30% in the external dimensions of the detection unit (loop area is 0.2 x 8.4 mm). They also developed a test-board design and a magnetic-field measuring method over a printed wiring pattern (microstrip line) which can be applied to LSI testers.

SPICE simulation of power supply current from LSI on PCB with a behavioral model

This paper proposes a new behavioral model of an LSI to simulate current in the power supply line of a PCB. The models impedance changes with time, thus ensuring simulation accuracy. The new model makes it possible to easily simulate the current in a PCB power supply line. Good agreement is obtained between simulated values and measured in experiments.