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This paper presents a novel seven-level (7L) voltage source converter for high-power medium-voltage applications. The proposed topology is an H-bridge connection o f two nested neutral-point clamped (NNPC) converters and is referred to as an HNNPC converter. This converter exhibits advantageous features, such as operating over a wide range o f output voltages, particularly for 10-15 kV applications, without the need to connect power semiconductors in series; high-quality output voltage; and fewer components relative to other classic seven-level topologies. A novel sinusoidal pulse width modulation technique is also developed for the proposed 7L-HNNPC converter to control flying capacitor voltages. One of the main features o f the control strategy is the independent application of control to each arm of the converter to significantly reduce the complexity of the controller. The performance of the proposed converter is studied under different operating conditions via MATLAB/Simulink simulation, and its feasibility is evaluated experimentally on a scaled-down prototype converter. [ABSTRACT FROM AUTHOR]

high speed, low jitter low voltage differential signaling (LVDS) output driver for high speed serial transmission is presented. Based on the comparison among four typical output driver architectures and the analysis of the output signal swing, an additional differential termination is addressed at the source of the driver to improve the signal integrity (SI). The stipulated common mode voltage is achieved over process, voltage, temperature (PVT) variations without trimming methodology, by means of a common mode feedback (CMFB) circuit and a novel high order temperature compensation bandgap reference. The simulation results show the temperature coefficient (TC) of the bandgap is only 1.77 ppm/°C. The whole driver circuit is implemented in SMIC 0.18 μm CMOS technology. It provides an output differential mode voltage of 567 mV and a common mode voltage of 1.201 V at 2 Gbps, and consumes 15.41 mA total current with a 2.5 V power supply. The output root mean square (RMS) jitter of the driver is only 7.65 ps. [ABSTRACT FROM AUTHOR]