Each PCB in the system should have at least one complete layer dedicated to the ground plane. Ideally, a double-sided board should have one side dedicated to ground and the other side for interconnections. In practice, this is not possible, since some of the ground plane will certainly have to be removed to allow for signal and power crossovers and vias. Nevertheless, as much area as possible s...

Scientists in the Crystallography Section at NIST/NBS made several outstanding contributions which greatly promoted the development and advancement of high pressure x-ray crystallography during the second-half of the 20th century. These milestone achievements or "firsts" included: (1) the invention of the lever-arm type diamond anvil cell (DAC) in 1958; (2) the development of DAC technology for...

A frequency synthesizer generates multiple frequencies from one or more frequency references. These devices have been used for decades, especially in communications systems. Many are based upon switching and mixing frequency outputs from a bank of crystal oscillators. Others have been based upon well understood techniques utilizing phase-locked loops (PLLs). This mature technology is illustrate...

We have designed, fabricated and measured a second-order multibit switched-capacitor complex bandpass ΔΣAD modulator to evaluate our new algorithms and architecture. We propose a new structure of a complex bandpass filter in the forward path with I, Q dynamic matching, that is equivalent to the conventional one but can be divided into two separate parts. As a result, the ΔΣ modulator, which emp...

A mixed-mode error correction scheme is described for multibit ADCs with resistor-string and switched-capacitor DACs. The correction circuit uses a simple calibration ADC and digital filtering. It operates in the background and remains effective even for very low oversampling ratios.

Pressure calibration for most diamond-anvil cell (DAC) experiments is mainly based on the ruby scale, which key to implementing this powerful tool high-pressure study. However, scale can often hardly be used programmably controlled DAC devices, especially piezoelectric-driving cells, where a continuous pressure required. In work, we present an effective gauge DACs made of Manganin metal four-pr...

BACKGROUND Corn stover is lignocellulosic biomass that has potential to be used as raw material for bioethanol production. In the current research, dilute ammonia pretreatment was used to improve the accessibility of corn stover carbohydrates to subsequently added hydrolytic enzymes. Some carbohydrates, however, were still present after enzymatic hydrolysis and fermentation. Hence, this researc...

Джерела опорної напруги та опорного струму є невід'ємною частиною будь-яких електронних схем. Особливо важливу роль джерела грають в аналогових схемах, від них залежать багато кількісних параметрів роботи Наприклад аналого-цифрових цифро-аналогових перетворювачах значення повної шкали визначається опорним джерелом напруги. Сьогодні існує досить різноманітних підходів щодо побудови схем джерел п...