Vicor's flexible route to RoHS compliance

For many manufacturers product compliance to the European environmental RoHS hazardous material standard will be compulsory by 1 July 2006. To help ease our customers' transition to RoHS compliance, Vicor will be offering our standard Brick products in both RoHS compliant and non-RoHS compliant options. Customers who manufacture using lead/tin solder processes can continue to use our existing non-RoHS compliant products which incorporate lead/tin connector pins. Customers transitioning to RoHS can now select RoHS-compatible pin styles.

Evaluation samples of most RoHS compliant products can be ordered now and volume production will follow shortly.

Most of the Vicor product range will be available in a RoHS compliant form by January 2006. For further details of our RoHS strategy, including a product roadmap, please visit the RoHS area of our website.

High-boost harmonic attenuator module

Vicor's high-boost VI-HAM is a universal
AC input, PFC front-end module that has
been optimised for use with Vicor's V375 series of DC-DC converters. A single high-boost VI-HAM may be used with any combination of V375 series DC-DC converters up to 600 Watts, resulting in a power conversion system with high power density, few components, and low cost

Parallelable versions of the VI-HAM are available for applications requiring over 600 Watts of output power. In addition, the high-boost VI-HAM is fully compatible with Vicor's VI-26x and VI-J6x series DC-DC converters, giving designers the freedom to choose from the industry's broadest selection of DC-DC converters with outputs from 2 to 95Vdc, at 50 to 600 Watts.

The VI-HAM consists of a full-wave rectifier, a proprietary high-frequency zero-current switching (ZCS) boost converter, and includes active inrush current limiting, over temperature and short circuit protection, control, and housekeeping circuitry. For further information click here.

Output voltage trimming

The nominal output voltage of Vicor's DC-DC converter can be trimmed up or down within a specified range. Most of our 1st Gen converters can be adjusted between -50% and +10% (except outputs between 10V and 15V, which are limited to a range of +/- 10%). All our 2nd Gen converters can be trimmed down to 10% or up to 110% of nominal output voltage.

Fixed set output trimming can be achieved using a single resistor or by using a potentiometer when variable outputs are required. The use of an OpAmp or DAC gives you more flexibility to change the output voltage dynamically. Care has to be taken not to exceed the maximum voltage rating of the control pin provided in our datasheets. Usually a minimum pre load is necessary to reach the lowest output voltage. Please contact Vicor's applications engineering for more details.

The trimming resistors, potentiometer, or active circuitry are connected to TRIM (1st Gen) or to SC (2nd Gen) respectively, and are referenced to the SENSE pins. Due to the lack of SENSE pins in our Micro modules, the trimming resistors are referenced to the -OUT and +OUT. To avoid noise being introduced into the module, the trim components should be located close to the module's pins.

For convenience, we provide trimming calculators for fixed and for variable output trimming on our web page. Please see both links below. To view the 1st Gen application manual. Please click here.

Click here for fixed output trimming calculators	Click here for variable output trimming calculators

MRI scanning system

The system is designed specifically for in-office musculoskeletal imaging, bringing MRI to the patient, and thus reducing the need for hospital visits.

The compact, modular design requires as little as 8.4m² and the low field MRI magnet is optimized for orthopedic use and imaging of extremities. Patients remain outside the magnet at all times during the examinations, enabling constant patient-technologist contact.

This MRI system uses Vicor's Junior modules in the temperature control system, where it is vitally important to keep the MRI magnets at a constant temperature.

3-D ultrasound systems

Some of you may remember the days when we could not make head nor tail of a pre-natal ultrasound. Those days are gone! Hi-tech ultrasounds now come in 3-D and are put on disks for parents to view at leisure in the comfort of their own homes and to share with family and friends.

Originally Vicor's 1st Gen modules were used to power these ultrasound systems, but now the 2nd Gen modules have taken their place. The ultrasound equipment designers chose Vicor because of the low noise and interference levels of our products, the high density that our modules can provide, and the excellent technical support that we give.

VSPOC: configure Westcor AC-DC products online

VSPOC is a new, easy-to-use online configuration tool for Westcor chassis-mounted, AC-DC power supplies. Use this flexible, powerful tool to specify and verify complete AC-DC power solutions, including PFC options, in real time. Designs can then be saved, reviewed and edited as required, along with any other designs you make using Vicor's configurator tools.

To design your AC-DC power supply go to VSPOC

New FAQs section on vicor-asia.com

In Vicor's new FAQ section you will find answers to a variety of questions about power supply design and related issues.

For example:

• What is PFC, and what does it mean for me?
• Do the Vicor modules need a heat sink?
• Do I need to fuse the input of the converter?

Click on any of the above links to get the answer. Or for more questions go to FAQ. If your question is not there, you can 'Ask an Apps' - send us your technical question online and we will get an answer to you in less than 24 hours. Just click to ask an apps.

Patrizio Vinciarelli: Chairman, President and CEO, Vicor Corp - and power design wizard!

Patrizio Vinciarelli founded Vicor in 1981 and has served as President since that time. In the early 1980s, Dr Vinciarelli invented "Zero Current Switching and Zero Voltage Switching" technologies, which enabled power converters to be designed that were much smaller and more efficient than conventional power converters. Vicor created the power component industry by offering its unique technologies as families of high-density "bricks" that can be used as building blocks to create virtually any power system. Dr Vinciarelli holds more than 75 US patents, with others pending.

From 1977 to 1980, Dr Vinciarelli was a Fellow at the Institute of Advanced Studies in Princeton, New Jersey and an instructor at Princeton University. From 1973 to 1976, he was a Fellow at CERN, the Center for Nuclear Research, in Geneva, Switzerland. Dr Vinciarelli received his doctorate in physics from the University of Rome, Italy. He now lives with his family in Boston.

Match the definitions to the terms (e.g. A2)!