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A two-chip system has been developed to simplify the conversion of analog TV signals into a digital format suitable for storage in a field store used in picture applications or for use in a computer environment. In this type of application, the system clock is usually required to be a discrete multiple of horizontal line frequency, i.e. line locked. The system consists of a bipolar signal processor driving a CMOS triple analog-to-digital converter. An external divider gives the required division ratio between the system clock and the TV horizontal line rate. Signals are accepted in all standard formats, i.e. NTSC/PAL/SECAM composite video, luminance with color difference signals, S-VHS, or RGB. Separate composite sync signals may be used in conjunction with these signals. Measurement results for the A/D converter are given. >

The recent trend towards integrating an entire transceiver, with all its RF/analog/DSP functions, on a single CMOS chip is a consequence of strong market demands on RF chip size, cost, reliability, battery-life, etc. The design of a modern RF CMOS chips generates various technical challenges due to circuit complexity, signal complexity, and integration issues. Advanced LSNA characterization and modeling of deep submicron devices are critical to modern RF CMOS circuit design. This paper reviews some of the RF device level modeling technologies required for the design of RFICs. The LSNA modeling is performed using Agilent's characterization, parameter extraction and simulation tools flow.

We report accurate laboratory measurements of selected methanol transition frequencies between 0.834 and 230 GHz in order to facilitate astronomical velocity analyses. New data have been obtained between 10 and 27 GHz and between 60 and 119 GHz. Emphasis has been put on known or potential interstellar maser lines as well as on transitions suitable for the investigation of cold dark clouds. Because of the narrow line widths (, 9 pages, 2 figures, A&A, in press

Recombination in forward conducting silicon power devices has been investigated by measuring the distribution of radiative recombination, and supplementally, the stored charge Q , extracted by rapid commutation. The "axial" radiation distribution, detected through a slit moving perpendicular to the junction interfaces of the test specimens, includes surface recombination according to quantitative expressions presented. The volume lifetime is determined from the axial radiation profile together with the distribution recorded in the lateral direction. The high-level lifetime in the base region of p+-s-n+structures, determined from the radiation technique, is much larger than that extrapolated from the effective lifetime, \tau_{eff} = Q/I ( I current), considering recombination in the emitter regions according to classical principles. Recombination in the emitter regions, determined as a function of the concentration in the base region at high injection levels, has a significant linear component, superposed on the normal (almost) square-law dependence. The source and the consequences of these components of emitter recombination are discussed. The results are shown typically for p+-s-n+rectifiers and thyristors with conventional low-gradient diffusion profiles, and those with p-emitter regions where an abrupt doping gradient in the otherwise normal diffused layer limits the effective base region.

The temperature dependence of the intrinsic radiative recombination coefficient B in silicon was measured from 100 to 400 °K. In contrast to previous calculations, B decreases with temperature. For interpretation of the measurements, a unique theory of the indirect radiative band-to-band and free exciton recombination is given. The decrease of B with increasing T is due to the decrease to the exciton concentration and of the Coulomb-enhancement of the band-to-band recombination rate. The latter however is smaller than the exciton recombination part even at room temperature. The constants of the exciton and band-to-band recombination are determined.

The radiative recombination rate R in silicon at 300°K was measured as a function of the electron and hole concentration n = p at high injection levels. Carriers were injected in a p-i-n device, and their concentration was measured by charge extraction. The equation R = B n p = B n2 was verified up to n = 2×1017 cm−3 The radiative recombination probability was found to be B = 1.1 × 10−14 cm3/s. Die Rate R der strahlenden Rekombination in Silizium wurde bei 300°K als Funktion der Elektronen- und Locherkonzentration n = p bei hoher Injektion gemessen. Die Ladungstrager wurden in eine p-i-n-Diode injiziert, und ihre Konzentration wurde durch Ladungsextraktion gemessen. Die Gleichung R = B n p = B n2 wurde bis zu n = 2× ×1017 cm−3 verifiziert. Der Koeffizient der strahlenden Rekombination wurde zu B = 1,1 × 10−14 cm3/s bestimmt.

Different gold concentration profiles in thyristors result in different switching behavior. The injected carrier concentration profiles which can be obtained from the local recombination radiation intensities give insight into these effects.

High-performance liquid chromatography (HPLC) in combination with thermospray mass spectrometry (LC/TSP-MS) is an important method for molecular weight determination of unknown compounds. In addition to the well-known ammonium acetate buffer (NH4OAc) the use of methylammonium acetate (CH3NH3OAc) in the positive- and ammonium formate (NH4OFo) in the negative-ion mode is recommended. Performing a second run with these buffers, even from spectra with only one single quasimolecular ion, an unequivocal molecular weight can be obtained. For correct assignment, the shift in mass of the corresponding quasimolecular ions in each mode is used. Finally, the use of a second buffer greatly facilitates the recognition of superimposed HPLC peaks.

Perfect isolation between power and control circuits in high-voltage converter equip­ment is obtained by optical thyristor triggering. Direct optical triggering of power thyristors and auxiliary thyristors with lasers or LEDs, i.e. triggering with an internally generated photocurrent, requires the development of highly trigger-sensitive thyristor gates. High trigger-power amplification and different methods of avoiding or compensating for fault triggering permit the design of light-activated thyristors which can be triggered with light power in the milliwatt range. The temperature dependence of turn-on properties and some relations to thyristor structures can be obtained from relatively simple charge-control model calculations.