Particle Swarm Optimization Framework for Low Power Testing of VLSI Circuits

Power dissipation in sequential circuits is due to increased toggling count of Circuit under Test, which depends upon test vectors applied. If successive test vectors sequences have more toggling nature then it is sure that toggling rate of flip flops is higher. Higher toggling for flip flops results more power dissipation. To overcome this problem, one method is to use GA to have test vectors of high fault coverage in short interval, followed by Hamming distance management on test patterns. This approach is time consuming and needs more efforts. Another method which is purposed in this paper is a PSO based Frame Work to optimize power dissipation. Here target is to set the entire test vector in a frame for time period 'T', so that the frame consists of all those vectors strings which not only provide high fault coverage but also arrange vectors in frame to produce minimum toggling

Thermoelectric and electrical properties of Ba

Thermoelectric and electrical characteristics investigation of M-type hexagonal ferrite, Ba0.5Sr0.5CoxRuxFe(12−2x)O19 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2), have been carried out from 303 K to 473 K. The static current density-electric field characteristics have been measured at room temperature. The Seebeck coefficient indicates n-type behavior at lower substitution and p-type conduction at higher substitution. The different electrical parameters are affected by change in grain size with substitution of Co2+ and Ru4+ ions. The existence of polarons is confirmed from increase in conductivity with frequency. The static conduction due to applied electric field is discussed qualitatively in terms of space charge limited current, ionic hopping, Poole-Frenkel and Schottky-Richardson mechanisms. The large current density has been observed at higher substitution

Elucidation of microwave absorption mechanisms in Co–Ga substituted Ba–Sr hexaferrites in X-band

The tunable microwave absorbers are used to combat the electromagnetic pollution created by the development of high speed electronic devices. In the present paper, we report microwave absorption characteristics of M-type Ba0.5Sr0.5CoxGaxFe12−2xO19 (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) hexagonal ferrite compositions prepared by using double sintering ceramic method. X-ray diffraction analysis of the prepared compositions revealed the formation of M-phase along with the minor traces of hematite in substituted compositions. The microwave absorption has been elucidated substantially through various mechanisms in the test frequency range from 8.2 to 12.4 GHz, which is still partially explored in literature. The substitution of Co2+ and Ga3+ ions enhances microwave absorption, bandwidth, decreases thickness and improves impedance matching. The hysteresis parameters also comply with the microwave absorption. The optimal reflection loss of − 29.74 dB is observed in the composition x = 0.2 at 8.28 GHz with 2.0 mm thickness. The investigated mechanisms of microwave absorption can be incorporated to optimize the absorption and design of the microwave absorbers

Tailoring of Electromagnetic Absorption in Substituted Hexaferrites from 8.2 GHz to 12.4 GHz

Microwave absorbers are an important topic of interest to mitigate electromagnetic interference. Here, we have investigated electromagnetic absorption properties of Ba0.5Sr0.5CoxInxFe12−2xO19 hexaferrite prepared by the conventional ceramic method. M-type hexagonal structure in the compositions was confirmed from x-ray diffraction analysis. The role of Co2+ and In3+, thickness of composition and frequency on the electromagnetic absorption in the ferrite compositions has been explored from 8.2 GHz to 12.4 GHz. It was found that both Co2+-In3+ increased microwave/electromagnetic absorption with broad bandwidth, decreased the thickness and enhanced impedance matching. The reflection loss of −39.99 dB was noted in the composition x = 0.2 for the thickness of 1.6 mm and a frequency of 11.14 GHz. The results conclude that investigated compositions of Ba0.5Sr0.5CoxInxFe12−2xO19 ferrite ameliorate absorber applications