Complementary Metal Oxide Semiconductor Systems Research Articles

Exploring Terahertz COMPLEMENTARY METAL OXIDE SEMICONDUCTOR Integrated Circuits: Advancements and Obstacles

The text provides a description of the characteristics of several NMOS and CMOS circuit approaches, as well as an explanation of the limitations associated with each technology. Next, the CMOS domino circuit, a novel form of circuit, is explained. This entails interconnecting dynamic CMOS gates in a manner that enables the activation of all gates in the circuit simultaneously using a single clock edge. Consequently, there is no need for intricate clocking methods, allowing the dynamic gate to operate at its maximum speed. This circuit features a basic mode voltage-controlled oscillator operating at 135 GHz in 80-nm COMPLEMENTARY METAL OXIDE SEMICONDUCTOR, a 405 GHz push-push voltage controller in 38-nm COMPLEMENTARY METAL OXIDE SEMICONDUCTOR with an on-chip patch antenna, a 128 GHz Schottky diode frequency doubler, a 170 GHz Schottky diode detector, a 600 GHz plasma wave detector in 122-nm COMPLEMENTARY METAL OXIDE SEMICONDUCTOR and a 40 GHz phase-locked loop with a frequency doubled output at 110 GHz. Given this and the trends in performance of n METAL OXIDE SEMICONDUCTOR transistors and Schottky diodes produced in complementary metal-oxide semiconductors, we lay out a plan for terahertz COMPLEMENTARY METAL OXIDE SEMICONDUCTOR systems and circuits, highlighting critical challenges that need to be addressed. With the advent of terahertz COMPLEMENTARY METAL OXIDE SEMICONDUCTOR

87%-Efficient 330-mW 0.6-<italic>μ</italic>m Single-Inductor Triple-Output Buck–Boost Power Supply

Microsystems that sense, process, and communicate data can save money, energy, and lives. Such varied functionality, however, demands power that can easily deplete a small battery. Integrating so many analog and digital functions can also imperil performance with noise and distortion. To survive all this with an exhaustible battery, blocks require several efficient power supplies that both buck and boost the battery voltage. Luckily, switched inductors are flexible and efficient, but also bulky. So what these microsensors need are single-inductor multiple-output supplies that buck and boost. But to reconfigure the inductor for such diverse operation requires many power-consuming switches. Plus, cycling between outputs requires time and delays response time. The single-inductor supply proposed bucks and boosts and cycles between outputs frequently with two input switches, one inductor, and one switch and one capacitor per output. Other buck–boost supplies either bypass the inductor or require one to two more switches and up to one more inductor and one more capacitor. The prototype presented here bucks two outputs and boosts one output with five switches by energizing the inductor to buck outputs first. By collecting sufficient energy this way, the inductor can feed boost outputs directly. A sixth switch engages only when boost power is greater than a threshold that the input voltage and buck power levels establish. This way, the 0.6- μ m complementary metal oxide semiconductor system bucks and boosts 2.7–4.0 V to 1.2, 1.8, and 4.0 V to deliver 80%−87% of the 379–412 mW drawn. The system cycles every 1–3 μ s and responds within 5–10 μ s.

A comparison of older and newer versions of intraoral digital radiography systems: Diagnosing noncavitated proximal carious lesions

The authors conducted a study to compare the accuracy of an older and newer version of two intraoral digital systems in terms of radiographic detection of proximal carious lesions. Under in vitro and standardized conditions, the authors obtained radiographs of 160 noncavitated proximal surfaces using the Digora FMX (Soredex, Tuusula, Finland), the Digora Optime, the Schick CDR (Schick Technologies, Long Island City, N.Y.) and the Schick CDR Wireless (Schick Technologies) systems. Eight observers recorded proximal carious lesions on a five-point confidence scale. The presence of caries was validated histologically. The new digital systems (Digora Optime and Schick CDR Wireless) had significantly higher sensitivities than their predecessors. The authors found no significant differences in specificity among the Digora FMX, Schick CDR and Schick CDR Wireless systems, all of which had a significantly higher specificity than did the Digora Optime system (P < .02). The positive predictive value for the Digora Optime system was affected by its high sensitivity and low specificity, and it was lower than that for the two CDR systems (P < .02). Regarding overall accuracy, the difference between the older and newer versions of the photostimulable storage phosphor and complementary metal oxide semiconductor systems was not statistically significant. However, the authors found more false-positive diagnoses made with the Digora Optime system than with the Digora FMX system. Though the difference in specificities was statistically significant, the authors question whether the difference between the Digora Optime and the other systems is clinically relevant. Therefore, dentists can purchase any of these systems after considering factors other than those evaluated in this study.