INVESTTGATION OF AGING EFFECTS FROM HIGH VOLTAGE PROFILES IN CERAMIC PHASE SHIFTER MATERIALS

2005 ◽  
Author(s):  
S. Stowell ◽  
L.C. Sengupta ◽  
E. Ngo ◽  
M.E. O'Day ◽  
R. Lancto
Keyword(s):  
High Voltage ◽  
Phase Shifter ◽  
Aging Effects ◽  
Ceramic Phase

A LOW-NOISE HIGH-VOLTAGE INTERFACE CIRCUIT FOR CAPACITIVE MEMS GYROSCOPE

2013 ◽  
Vol 22 (09) ◽  
pp. 1340019 ◽  
Author(s):  
RAN FANG ◽  
WENGAO LU ◽  
GUANNAN WANG ◽  
TINGTING TAO ◽  
YACONG ZHANG ◽  
...  
Keyword(s):  
High Voltage ◽  
Integrated Circuit ◽  
Phase Shifter ◽  
Low Noise ◽  
Interface Circuit ◽  
Mems Gyroscope ◽  
Level Shifter ◽  
Capacitive Mems ◽  
On Chip ◽  
A Charge

This paper presents a high-voltage control and readout interface circuit implemented for capacitive Micro-Electro-Mechanic System (MEMS) gyroscope. A charge sensitive amplifier (CSA) with chopper technique is used to accomplish low-noise capacitive sensing. The stabilization of the closed drive loop is maintained by an auto gain controller (AGC) and an adjustable phase shifter. The outputs of the ASIC directly drive the gyroscope after buffered by an on-chip high-voltage level shifter. The chip is fabricated in a 0.35 um 5 V/12 V Bipolar, CMOS and DMOS (BCD) process. The test of the chip is performed with a MEMS vibratory gyroscope. The result shows that the Application Specific Integrated Circuit (ASIC) can ensure a stable oscillation in the drive axis, and the noise floor is 0.0015°/s/√Hz within 100 Hz.

scholarly journals An active high-voltage divider and phase shifter

1987 ◽  
Vol IM-36 (2) ◽  
pp. 362-368 ◽  
Author(s):  
Oskars Petersons ◽  
S. P. Mehta
Keyword(s):  
High Voltage ◽  
Phase Shifter ◽  
Voltage Divider

High Voltage Electron Microscopy of Ion-Milled Dental Enamel

1974 ◽  
Vol 32 ◽  
pp. 60-61
Author(s):  
L. D. Ackerman ◽  
S. H. Y. Wei
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Third Molar ◽  
Polarized Light ◽  
Dental Enamel ◽  
Longitudinal Section ◽  
Ion Milling ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron

Mature human dental enamel has presented investigators with several difficulties in ultramicrotomy of specimens for electron microscopy due to its high degree of mineralization. This study explores the possibility of combining ion-milling and high voltage electron microscopy as a means of circumventing the problems of ultramicrotomy.A longitudinal section of an extracted human third molar was ground to a thickness of about 30 um and polarized light micrographs were taken. The specimen was attached to a single hole grid and thinned by argon-ion bombardment at 15° incidence while rotating at 15 rpm. The beam current in each of two guns was 50 μA with an accelerating voltage of 4 kV. A 20 nm carbon coating was evaporated onto the specimen to prevent an electron charge from building up during electron microscopy.

Three-Dimensional Visualization of the T-System of Frog Muscle Using High Voltage Electron Microscopy and a Lanthanum Stain

1977 ◽  
Vol 35 ◽  
pp. 570-571 ◽  
Author(s):  
Lee D. Peachey ◽  
Clara Franzini-Armstrong
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Three Dimensional ◽  
Biological Tissues ◽  
High Voltage Electron Microscopy ◽  
Transverse Tubular System ◽  
Peroxidase Reaction ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
T System

The effective study of biological tissues in thick slices of embedded material by high voltage electron microscopy (HVEM) requires highly selective staining of those structures to be visualized so that they are not hidden or obscured by other structures in the image. A tilt pair of micrographs with subsequent stereoscopic viewing can be an important aid in three-dimensional visualization of these images, once an appropriate stain has been found. The peroxidase reaction has been used for this purpose in visualizing the T-system (transverse tubular system) of frog skeletal muscle by HVEM (1). We have found infiltration with lanthanum hydroxide to be particularly useful for three-dimensional visualization of certain aspects of the structure of the T- system in skeletal muscles of the frog. Specifically, lanthanum more completely fills the lumen of the tubules and is denser than the peroxidase reaction product.

Resolution, Contrast and Interpretation of HVEM Images of Crystals

1973 ◽  
Vol 31 ◽  
pp. 228-229
Author(s):  
L. E. Thomas ◽  
J. S. Lally ◽  
R. M. Fisher
Keyword(s):  
High Voltage ◽  
Chromatic Aberration ◽  
Crystalline Materials ◽  
Resolution Parameter ◽  
Instrument Resolution ◽  
Imaging Conditions ◽  
Beam Excitation ◽  
Optimum Imaging

In addition to improved penetration at high voltage, the characteristics of HVEM images of crystalline materials are changed markedly as a result of many-beam excitation effects. This leads to changes in optimum imaging conditions for dislocations, planar faults, precipitates and other features.Resolution - Because of longer focal lengths and correspondingly larger aberrations, the usual instrument resolution parameter, CS174 λ 374 changes by only a factor of 2 from 100 kV to 1 MV. Since 90% of this change occurs below 500 kV any improvement in “classical” resolution in the MVEM is insignificant. However, as is widely recognized, an improvement in resolution for “thick” specimens (i.e. more than 1000 Å) due to reduced chromatic aberration is very large.

Radiation-Induced Precipitation at Thin Foil Surfaces in Ni-Be Alloys

1982 ◽  
Vol 40 ◽  
pp. 598-599
Author(s):  
T. Mukai ◽  
T. E. Mitchell
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Electron Irradiation ◽  
High Vacuum ◽  
Thin Foil ◽  
Homogeneous Precipitation ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Radiation Induced

Radiation-induced homogeneous precipitation in Ni-Be alloys was recently observed by high voltage electron microscopy. A coupling of interstitial flux with solute Be atoms is responsible for the precipitation. The present investigation further shows that precipitation is also induced at thin foil surfaces by electron irradiation under a high vacuum.

The Reduction of Chromatic Aberrations Due to Instrumental Instabilities

1971 ◽  
Vol 29 ◽  
pp. 14-15
Author(s):  
J. S. Lally ◽  
R. Evans
Keyword(s):  
Electron Microscope ◽  
High Voltage ◽  
Focal Length ◽  
Chromatic Aberration ◽  
Objective Lens ◽  
Usual Practice ◽  
Voltage Electron ◽  
Short Focal Length ◽  
Chromatic Aberrations ◽  
Electron Microscopes

One of the instrumental factors often limiting the resolution of the electron microscope is image defocussing due to changes in accelerating voltage or objective lens current. This factor is particularly important in high voltage electron microscopes both because of the higher voltages and lens currents required but also because of the inherently longer focal lengths, i.e. 6 mm in contrast to 1.5-2.2 mm for modern short focal length objectives.The usual practice in commercial electron microscopes is to design separately stabilized accelerating voltage and lens supplies. In this case chromatic aberration in the image is caused by the random and independent fluctuations of both the high voltage and objective lens current.

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