A robust high-efficiency cross-coupled charge pump circuit without blocking transistors

This document is the Accepted Manuscript version of the following article: Minglin Ma, Xinglong Cai, Yichuang Sun, and Nike George, ‘A robust high-efficiency cross-coupled charge pump circuit without blocking transistors’, Analog Integrated Circuits and Signal Processing, Vol. 95 (3): 395-401, June 2018. Under embargo until 16 March 2019. The final publication is available at Springer via: https://doi.org/10.1007/s10470-018-1149-xA fully integrated cross-coupled charge pump circuit with a new clock scheme has been presented in this paper. The new clock scheme ensures that all NMOS pre-charge transistors are turned off when the voltages of main clock signals are high. Notably, all PMOS transfer transistors will be turned off when the voltages of the main clock signals are low. As a result, the charge pump eliminates all of the reversion power loss and reduces the ripple voltage. The proposed charge pump has a better performance even in scenarios where the main clock signals are mismatched. The proposed charge pump circuit was simulated using spectre in the TSMC 0.18 µm CMOS process. The simulation results show that the proposed charge pump circuit has a high voltage conversion efficiency and low ripple voltage.Peer reviewe

High Efficiency Cross-Coupled Charge Pump Circuit with Four-Clock Signals

© Allerton Press, Inc. 2018A fully integrated cross-coupled charge pump circuit for boosting dc-to-dc converter applications with four-clock signals has been proposed. With the new clock scheme, this charge pump eliminates all of the reversion power loss and reduces the ripple voltage. In addition, the largest voltage differences between the terminals of all transistors do not exceed the power supply voltage for solving the gate-oxide overstress problem in the conventional charge pump circuits and enhancing the reliability. This proposed charge pump circuit does not require any extra level shifter; therefore, the power efficiency is increased. The proposed charge pump circuit has been simulated using Spectre in the TSMC 0.18 μm CMOS process. The simulation results show that the maximum voltage conversion efficiency of the new 3-stage cross-coupled circuit with an input voltage of 1.5Vis 99.8%. According to the comparison results of the conventional pump and the enhanced charge pump proposed, the output ripple voltage has been significantly reduced.Peer reviewe

Non-Invasive Induction Link Model for Implantable Biomedical Microsystems: Pacemaker to Monitor Arrhythmic Patients in Body Area Networks

In this paper, a non-invasive inductive link model for an Implantable Biomedical Microsystems (IBMs) such as, a pacemaker to monitor Arrhythmic Patients (APs) in Body Area Networks (BANs) is proposed. The model acts as a driving source to keep the batteries charged, inside a device called, pacemaker. The device monitors any drift from natural human heart beats, a condition of arrythmia and also in turn, produces electrical pulses that create forced rhythms that, matches with the original normal heart rhythms. It constantly sends a medical report to the health center to keep the medical personnel aware of the patient's conditions and let them handle any critical condition, before it actually happens. Two equivalent models are compared by carrying the simulations, based on the parameters of voltage gain and link efficiency. Results depict that the series tuned primary and parallel tuned secondary circuit achieves the best results for both the parameters, keeping in view the constraint of coupling co-efficient (k), which should be less than a value \emph{0.45} as, desirable for the safety of body tissues.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

Ion drag EHD micropump with single walled carbon nanotube (SWCNT) electrodes

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.Ion drag electrohydrodynamic (EHD) micropumps are promising in a number of micro-scale applications due to its small form factor, low power consumption, ability to work with dielectric heat transfer fluids, good controllability and absence of any moving parts. Ion drag EHD micro-pumps have been studied widely and the pressure head has been reported to depend on electrode material (i.e., work function), geometric configuration, electrode surface topology and applied electric field. One drawback of such pumps is the relatively low pressure head generation and high threshold voltage required for the onset of charge injection for practical applications. The presence of micro/nano features with sharp asperities on the emitter electrodes is likely to enhance the local electric field and charge injection significantly and thus, the pressure generation. The objective of this work is to investigate the effect of surface topology on the charge injection and pressure generation in HFE 7100. Experiments were performed using micropumps with smooth and single wall carbon nanotube (SWCNT) deposited on smooth gold electrodes. A lower threshold voltage, higher charge injection and pressure head was found for the micropump with SWCNT deposited on smooth electrodes compared to the no deposition case

Synchronization modulation increases transepithelial potentials in MDCK monolayers through Na/K pumps

Peer reviewedPublisher PD

A hybrid metal/semiconductor electron pump for quantum metrology

Electron pumps capable of delivering a current higher than 100pA with sufficient accuracy are likely to become the direct mise en pratique of the possible new quantum definition of the ampere. Furthermore, they are essential for closing the quantum metrological triangle experiment which tests for possible corrections to the quantum relations linking e and h, the electron charge and the Planck constant, to voltage, resistance and current. We present here single-island hybrid metal/semiconductor transistor pumps which combine the simplicity and efficiency of Coulomb blockade in metals with the unsurpassed performances of silicon switches. Robust and simple pumping at 650MHz and 0.5K is demonstrated. The pumped current obtained over a voltage bias range of 1.4mV corresponds to a relative deviation of 5e-4 from the calculated value, well within the 1.5e-3 uncertainty of the measurement setup. Multi-charge pumping can be performed. The simple design fully integrated in an industrial CMOS process makes it an ideal candidate for national measurement institutes to realize and share a future quantum ampere

Evaluation of novel depressed collector for linear-beam microwave tubes

Evaluation tests to demonstrate feasibility of increasing efficiency of linear beam microwave tubes using novel depressed collecto