The area, speed and power consumption of oversampled data converters were governed largely by decimation filters in sigma delta A/D converters. The paper presented a design and implementation of a ...low power and high-speed sigma delta digital decimation filter which it was designed by top-down method. The decimation filter consists of a modified cascaded integrator-comb (CIC) decimation filter and two-stage half-band filter. The proposed CIC filter has 15% less hardware and 53% power saving compared to conventional CIC filters. The filter is implemented using 0.6-/spl mu/m CMOS standard cell and contains 6,560 equivalent gates resulting in a power consumption of only 35 mW from a 5-V supply. The decimation filter is very suitable for high-order sigma delta converters.
The sandwich transducer structure is comprised of three components along its main axis: the back metal cap, piezoelectric ceramic stack and the horn. The purpose of this work is to present a ...simplified method, referred as the equivalent length algorithm, to design the actuator parameters including each segment length and the resonance frequency fs. The actuator length L and the propagation wavelength λ along its main axis satisfy the standing wave theory. So, define an equivalent length coefficient for each part of the actuator, and then the sandwich structure is regarded as a single material cylindrical rod with equivalent length L'. According to the standing wave theory, the equivalent length L' of the actuator can be determined with the given resonance frequency fs, or vice versa. The phase length of each part of the actuator in the standing wave is optimized freely in the design procedure. The actual length of each part of the actuator is determined by the equivalent length coefficient. Finally, the resonance frequencies of three given actuators are calculated with this method. They are compared with those obtained through Ansys simulation and those measured by an impedance analyzer. The results show agreement.
(C
9
H
7
)Cl
2
(THF)
3
HO was synthesized from C
9
H
7
Na and HoCl
3
(0.8:1 mole ratio) in THF and its molecular structure was characterized by elemental analyses, IR spectrum and single crystal ...X-ray diffraction. The crystal is monoclinic, space group P2
1
/m with a = 10.384(5), b = 11.850(5), c = 11.827(5) Å, β = 108.03(5)° and Dc = 1.36 gcm
−3
for Z = 2; 2181 reflections were observed and considered. The holmium atom has a distorted octahedral geometry with one five-membered ring centroid of an indenyl ligand, three THF oxygen atoms and two chloride anions. The average Ho-C, Ho-CI and Ho-O distances are 2.675, 2.612 and 2.382 Å, respectively.
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