Design and analysis of a boosted pierce oscillator using MEMS SAW resonators

This paper highlights the design and analysis of a pierce oscillator circuit for CMOS MEMS surface acoustic wave resonators. The boosted pierce topology using two, three-stage cascode amplifiers provides sufficient gain to counteract the high insertion losses of - 65 dB at 1.3 GHz of the SAW resonator. For accurate prediction of the oscillator’s performance before fabrication, circuit design utilized touchstone S2P measurement results of the MEMS SAW resonator, which provides better results compared to the conventional method of using equivalent circuit simulations. This circuit was designed using Silterra’s 0.13 lm CMOS process. It has low power consumption of 1.52 mW with high voltage swing 0.10–0.99 V. All simulations were conducted using Cadence Design Systems and results indicate that phase noise of 92.63 dBc at 1 MHz

Real time digital alarm clock with microprogrammed control unit

Digital system design based on Field Programmable Logic Array (FPGA) is a method of choice for digital product development as it provides faster time to realize. Design software such as Xilinx ISE allows the designer to design and implement a new system on FPGA chip. Behavior of FPGA which can be defined by using VHDL provides powerful high-level constructs for describing complex logic and supports modular design methodology. Real Time Digital Alarm Clock with implementation of microprogrammed control unit is developed in this project. It is one of digital design that uses VHDL as source code and microprogrammed control unit instead of hardwired one with downloading capability to FPGA based Spartan-3 Development Board. Clocked sequential state machines are normally designed using one of two general approaches: the traditional gate and flip-flop approach or microprogramming. The microprogrammed approach to implementing control state machine has been widely used since the early 1960s and has the advantages of structured programming and fixed timing characteristics. This changed around 1990 with the widespread use of hardware description languages such as VHDL. One of the reasons for the popularity of microprogramming is that it translates the hardware design problem into a programming problem, making it tractable to a wider range of designers. Control information is stored in the microprogram memory and a new microinstruction is fetched from memory at every clock cycle. Since program changes only require a change in memory contents, the rate at which the controller can be clocked does not change, no matter how significant the program change. This is in contrast to the traditional gate and flipflop approach where changes can drastically impact the logic equations, number of gates, and clock frequency

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Low power and high voltage swing cascode Pierce oscillator for MEMS SAW resonators

The design of a cascode Pierce oscillator circuit with separation supply for a MEMS surface acoustic wave resonator is proposed. The cascode Pierce topology provides sufficient gain to counteract the high insertion losses of -65dB at 1.3GHz of the SAW resonator. This circuit was designed using Silterra's 0.13um CMOS process and has low power consumption of 1.52mW with high voltage swing 0.10V to 0.99V. All simulations were conducted using Cadence Design Systems. Simulated Phase Noise is 92.63dBc at 1MHz