Researchers at the University of Cincinnati have found a way both to lower the cost and improve the power conversion efficiency of polymer solar cells, which offer potential use in applications such as sensors, lighting, and consumer products. The researchers found that by adding a small amount of graphene nanoflakes to such cells as a charge transporter, they were able to achieve a threefold increase in efficiency. For more, see "UC Researchers Report on Discovery to Make Solar Power Less Expensive and More Efficient."
By adding a small amount of graphene nanoflakes to polymer solar cells -- which are thinner and more flexible than silicon solar cells, but not as efficient -- researchers have achieved a threefold increase in efficiency.
(Source: University of Cincinnati)
Researchers at the University of Auckland, New Zealand have developed a small, wearable electromagnetic energy harvester that harvests human vibrational kinetic energy to extend the operating life of biomedical devices. Comprising a snake-shaped silicone cantilever, a coil, and an NdFeB magnet, the device has an approximately 6.6-Hz resonant frequency and -10-mVpp output when tested with an acceleration of 0.3 g. The output increases to approximately -40 mVpp when tested at 1.5 g -- similar to the acceleration experienced when a person walks. For more, see "An Energy Harvester From Human Vibrational Kinetic Energy for Wearable Biomedical Devices."
A report from research firm Navigant Research forecasts that wireless charging systems for electric vehicles will grow to exceed 300,000 in annual sales by 2022 from just a few hundred in 2014. The report, "Wireless Charging Systems for Electric Vehicles," predicts that several developments in 2013 portended the beginning of a "new phase" in this market, including Bosch's agreement with the maker of the Plugless Power system, as well as the establishment of a standard frequency for wireless EV charging by the Wireless Power Transfer Task Force of the Society of Automotive Engineers.
In product news, NXP Semiconductors demonstrated a new Qi wireless charging transmitter that integrates all the circuits for a 5-V mobile phone charger in a package measuring 5 x 5 mm. The NXQ1TXA5 system-on-chip integrates a power controller, DSP, voltage regulation, foreign object detection, a full-bridge power stage to drive the transmitter coil, and circuits for on-chip current and voltage measurement.
Linear Technology announced an energy harvester PMIC designed to extend the life of a primary battery in low-power wireless systems. Using a small step-up transformer, the LTC3107 dc/dc converter operates from inputs as low as 20 mV and has a 2.2-V LDO output.
A new family of POL dc/dc modules from CUI incorporates the company's Solus Power Topology. The NDM3ZS-60 series converter modules offer a 60-A output in ultra-low-profile vertical and horizontal packages.
Bourns has announced additions to its high-power TVS diodes for DC bus protection applications. Offering 58-V and 76-V standoff voltages, respectively, the PTVS6-058C-TH/PTVS6-076C-TH feature enhanced temperature performance to meet circuit protection requirements for power line surges and indirect lightning strikes in AC and DC power-line applications.
Microchip Technology introduced two energy-measurement AFEs for multiple load power monitoring. The MCP3913 and MCP3914 integrate six and eight 24-bit delta-sigma ADCs, respectively, with 94.5 dB SINAD, -106.5 dB THD and 112 dB SFDR.
XP Power announced a series of fan-cooled rugged 650-W ac/dc power supplies intended for heavy-use industrial applications. The HHP650 series complies with MIL-STD-810F and ANSI/ISA, can accommodate an input range from 85 to 305 VAC, and can deliver up to 780 W at high line input.
International Rectifier has introduced an ultra-fast 1400-V IGBT optimized for induction heating and soft switching applications. The IRG7PK35UD1PbF features a typ. VCE(ON) of 2.00 V and is available in a TO-247 package.
Active-Semi International has announced the availability of its Qi-certified WPC Wireless charger reference designs. The PAC5220WP wireless power platform enables scalability to wide-input DC, universal AC inputs, and up to 150W of power delivery.
Finally, Murata Power Solutions has introduced an open-frame quarter brick dc/dc converter for wireless backhaul and smart grid applications. The 12-VDC/20-A single-output UWQ-12/20-T48 series is DOSA compatible and measures 58.4 x 36.8 x 11.7 mm.