An Output Bandwidth Optimized 200-Gb/s PAM-4 100-Gb/s NRZ Transmitter With 5-Tap FFE in 28-nm CMOS

This article presents a 200-Gb/s pulse amplitude-modulation four-level (PAM-4) and 100-Gb/s non-return-to-zero (NRZ) transmitter (TX) in 28-nm CMOS technology. To achieve the target data rate, the output bandwidth and swing of the proposed TX are optimized by minimizing the output capacitance of the 4:1 multiplexer (MUX) and driver stage with pull-up current sources and adopting a fully reconfigurable 5-tap feed-forward equalizer (FFE). The key circuit includes a segmented 8:4 MUX and 4:1 MUX/driver, a thermal encoder and retimer, and a flexible clock distribution network. Using the layout generated with Berkeley Analog Generator (BAG), the proposed TX achieves an eye opening with >52.9-mV eye height, 0.36 UI eye width, >98% RLM, and 4.63 pJ/b at 200-Gb/s PAM-4 signaling under >6-dB channel loss at 50 GHz, demonstrating the highest data rate achieved using a planar process.Electronic Instrumentatio

Development of laser-induced breakdown spectroscopy (LIBS) with timed ablation to improve detection efficiency

<p>A laser-induced breakdown spectrometer (LIBS) was developed for determining the elemental composition of individual airborne particles. The system employs two lasers focused on a narrow beam of particles. A continuous wave laser placed upstream scatters light from particles, while a pulse laser downstream ablates the particles. The scattered light from the upstream laser is used to trigger the downstream pulse laser, resulting in more accurate hitting of the particles than a free-firing laser system without the triggering signal (i.e., constant pulse laser firing). Various laboratory-generated aerosols (NaCl, MgCl₂, KCl, and CaCl₂) were used to evaluate the newly developed LIBS system. Particles were tightly focused into a center line with a sheath air focusing system using an optimum aerosol-to-sheath air velocity ratio. The locations of both the scattering laser and pulse laser beams were precisely controlled by a motorized X-Y stage controller. Data showed that for the LIBS with the triggering system, the hitting efficiency (%) of particles (200–600 nm) significantly increased (e.g., 350 nm particles had more than 26 times higher hitting efficiency at 1,000 particles/cm³), and much lower limits of particle size (∼200 nm) and number concentration (<100 particles/cm³) were achieved compared to the free-firing laser condition. Additionally, the hitting rate (hits/min) significantly increased with the triggering system. Our results suggest that the LIBS with the triggering system can be useful for real-time detection of elements of particles existing at low number concentrations (e.g., atmospheric particles) and for the determination of the variation of elemental composition among particles.</p> <p>© 2017 American Association for Aerosol Research</p

A 200Gb/s PAM-4 Transmitter with Hybrid Sub-Sampling PLL in 28nm CMOS Technology

This paper presents a complete 200Gb/s PAM-4 transmitter (TX) in 28nm CMOS technology. The transmitter features a hybrid sub-sampling PLL (SSPLL) with a delta-sigma (?S) modulator, clock distribution network with flexible timing control, and data path with a hybrid 5-tap Feed-Forward Equalizer (FFE) and T-coil for bandwidth extension. The prototype chip achieves 4.69 pJ/bit efficiency, 54mV eye height, 0.27UI eye width, and 97% RLM under -6dB channel loss at 50GHz. Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic Instrumentatio

Enhanced N‑type Semiconducting Performance of Asymmetric Monochlorinated Isoindigo-based Semiregioregular Polymers under Dynamic Forces

The asymmetric monochlorination strategy not only effectively addresses the steric issues in conventional dichlorination but also enables the development of promising acceptor units and semiregioregular polymers. Herein, monochlorinated isoindigo (1CIID) is successfully designed and synthesized by selectively introducing single chlorine (Cl) atoms. Furthermore, the 1CIID copolymerizes with two donor counterparts, centrosymmetric 2,2′-bithiophene (2T) and axisymmetric 4,7-di(thiophen-2-yl)benzo[1,2,5]thiadiazole (DTBT), forming two polymers, P1CIID-2T and P1CIID-DTBT. These polymers exhibit notable differences in backbone linearity and dipole moments, influenced by the symmetry of their donor counterparts. In particular, P1CIID-2T, which contains a centrosymmetric 2T unit, demonstrates a linear backbone and a significant dipole moment of 10.20 D. These properties contribute to the favorable film morphology of P1CIID-2T, characterized by highly ordered crystallinity in the presence of fifth-order (500) X-ray diffraction peaks. Notably, P1CIID-2T exhibits a significant improvement in molecular alignment under dynamic force, resulting in over 8-fold improvement in the performance of organic field-effect transistor (OFET) devices, with superior electron mobility up to 1.22 cm2 V−1 s−1. This study represents the first synthesis of asymmetric monochlorinated isoindigo-based conjugated polymers, highlighting the potential of asymmetric monochlorination for developing n-type semiconducting polymers. Moreover, our findings provide valuable insights into the relationship between the molecular structure and properties