2,573 research outputs found
Digital Detection of Oxide Breakdown and Life-Time Extension in Submicron CMOS Technology
An approach is introduced to extend the lifetime of high-voltage analog circuits in CMOS technologies based on redundancy, like that known for DRAMS. A large power transistor is segmented into N smaller ones in parallel. If a sub-transistor is broken, it is removed automatically from the compound transistor. The principleis demonstrated in an RF CMOS Power Amplifier (PA) in standard 1.2V 90nm CMOS
Trends and challenges in VLSI technology scaling towards 100 nm
Summary form only given. Moore's Law drives VLSI technology to continuous increases in transistor densities and higher clock frequencies. This tutorial will review the trends in VLSI technology scaling in the last few years and discuss the challenges facing process and circuit engineers in the 100nm generation and beyond. The first focus area is the process technology, including transistor scaling trends and research activities for the 100nm technology node and beyond. The transistor leakage and interconnect RC delays will continue to increase. The tutorial will review new circuit design techniques for emerging process technologies, including dual Vt transistors and silicon-on-insulator. It will also cover circuit and layout techniques to reduce clock distribution skew and jitter, model and reduce transistor leakage and improve the electrical performance of flip-chip packages. Finally, the tutorial will review the test challenges for the 100nm technology node due to increased clock frequency and power consumption (both active and passive) and present several potential solution
Double resonant absorption measurement of acetylene symmetric vibrational states probed with cavity ring down spectroscopy
A novel mid-infrared/near-infrared double resonant absorption setup for
studying infrared-inactive vibrational states is presented. A strong
vibrational transition in the mid-infrared region is excited using an idler
beam from a singly resonant continuous-wave optical parametric oscillator, to
populate an intermediate vibrational state. High output power of the optical
parametric oscillator and the strength of the mid-infrared transition result in
efficient population transfer to the intermediate state, which allows measuring
secondary transitions from this state with a high signal-to-noise ratio. A
secondary, near-infrared transition from the intermediate state is probed using
cavity ring down spectroscopy, which provides high sensitivity in this
wavelength region. Due to the narrow linewidths of the excitation sources, the
rovibrational lines of the secondary transition are measured with sub-Doppler
resolution. The setup is used to access a previously unreported symmetric
vibrational state of acetylene, in the
normal mode notation. Single-photon transitions to this state from the
vibrational ground state are forbidden. Ten lines of the newly measured state
are observed and fitted with the linear least-squares method to extract the
band parameters. The vibrational term value was measured to be at 9775.0018(45)
, the rotational parameter was 1.162222 ,
and the quartic centrifugal distortion parameter was 3.998(62), where the numbers in the parenthesis are one-standard
errors in the least significant digits
Superfluidity in a Doped Helium Droplet
Path Integral Monte Carlo calculations of the superfluid density throughout
^4He droplets doped with linear impurities (HCN)_n are presented. After
deriving a local estimator for the superfluid density distribution, we find a
decreased superfluid response in the first solvation layer. This effective
normal fluid exhibits temperature dependence similar to that of a
two-dimensional helium system.Comment: 4 pages, 6 figure
Fokken met biologische stieren
Robuuste koeien. Dat staat bovenaan het wensenlijstje van veel biologische melkveehouders. Veel melkveehouders kruisen daarom hun koeien met âouderwetseâ rassen. De Themawerkgroep Fokkerij van het bedrijfsnetwerk biologische melkveehouderij probeert daarnaast een eigen biologische KI-programma te ontwikkele
An audio FIR-DAC in a BCD process for high power Class-D amplifiers
A 322 coefficient semi-digital FIR-DAC using a 1-bit PWM input signal was designed and implemented in a high voltage, audio power bipolar CMOS DMOS (BCD) process. This facilitates digital input signals for an analog class-D amplifier in BCD. The FIR-DAC performance depends on the ISI-resistant nature of this PWM-signal. An impulse response with only positive coefficients was chosen, because of its resistance to deadzone and mismatch. With a DAC current of 0.5 mA, the dynamic range is 111 dB (A-weighted), with SINAD = 103 dB (A-weighted). The current consumption is 1mA for the analog part and 4.8 mA for the digital part. The power consumption is 29 mW at V/sub dd/ = 5 V and the chip area is 2 mm/sup 2/ including the reference diode that can be shared by more channels
Entrance Channel X-HF (X=Cl, Br, and I) Complexes studied by High-Resolution Infrared Laser Spectroscopy in Helium Nanodroplets
Rotationally resolved infrared spectra are reported for halogen atom - HF
free radical complexes formed in helium nanodroplets. An effusive pyrolysis
source is used to dope helium droplets with Cl, Br and I atoms, formed by
thermal dissociation of Cl, Br and I. A single hydrogen fluoride
molecule is then added to the droplets, resulting in the formation of the X-HF
complexes of interest. Analysis of the resulting spectra confirms that the
observed species have ground electronic states, consistent with
the linear hydrogen bound structures predicted from theory. Stark spectra are
also reported for these species, from which the permanent electric dipole
moments are determined.Comment: 41 pages, 16 figures, 5 table
A high-resolution infrared spectroscopic investigation of the halogen atom-HCN entrance channel complexes solvated in superfluid helium droplets
Rotationally resolved infrared spectra are reported for the X-HCN (X = Cl,
Br, I) binary complexes solvated in helium nanodroplets. These results are
directly compared with that obtained previously for the corresponding X-HF
complexes [J. M. Merritt, J. K\"upper, and R. E. Miller, PCCP, 7, 67 (2005)].
For bromine and iodine atoms complexed with HCN, two linear structures are
observed and assigned to the and ground
electronic states of the nitrogen and hydrogen bound geometries, respectively.
Experiments for HCN + chlorine atoms give rise to only a single band which is
attributed to the nitrogen bound isomer. That the hydrogen bound isomer is not
stabilized is rationalized in terms of a lowering of the isomerization barrier
by spin-orbit coupling. Theoretical calculations with and without spin-orbit
coupling have also been performed and are compared with our experimental
results. The possibility of stabilizing high-energy structures containing
multiple radicals is discussed, motivated by preliminary spectroscopic evidence
for the di-radical Br-HCCCN-Br complex. Spectra for the corresponding molecular
halogen HCN-X complexes are also presented.Comment: 20 pages, 15 figures, 6 tables, RevTe
A 0.1-to-1.2GHz tunable 6th-order N-path channel-select filter with 0.6dB passband ripple and +7dBm blocker tolerance
Radio receivers should be robust to large out-of-band blockers with small degradation in their sensitivity. N-path mixers can be used as mixer-first receivers [1] with good linearity and RF filtering [2]. However, 1/f noise calls for large active device sizes for IF circuits and high power consumption. The 1/f noise issue can be relaxed by having RF gain. However, to avoid desensitization by large out-of-band blockers, a bandpass filter (BPF) with sharp cut-off frequency is required in front of the RF amplifiers. gm-C BPFs suffer from tight tradeoffs among DR, power consumption, Q and fc. Also, on-chip Q-enhanced LC BPFs [3] are not suitable due to low DR, large area and non-tunability. Therefore, bulky and non-tunable SAW filters are used. N-path BPFs offer high Q while their center frequency is tuned by the clock frequency [2]. Compared to gm-C filters, this technique decouples the required Q from the DR. The 4-path filter in [4] has only 2nd-order filtering and limited rejection. The order and rejection of N-path BPFs can be increased by cascading [5], but this renders a âroundâ passband shape. The 4th-order 4-path BPF in [6] has a âflatâ passband shape and high rejection but a high NF. This work solves the noise issue of [6] while achieving the same out-of-band linearity and adding 25dB of voltage gain to relax the noise requirement of the subsequent stages
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