LONDON Ė Toshiba has announced that this month it will start production of white light emitting diodes intended for use by makers of general purpose and industrial lighting using Bridgelux technology.
The white LEDs are made using gallium nitride grown on 200-mm diameter wafers of silicon. Toshiba said it plans to ramp capacity up to 10 million LEDs per month and said it wants to secure a 10 percent market share by 2016.
Production of LED chips is typically done on 2- to 4-inch sapphire wafers. Bridgelux Inc. (Livermore, Calif.) developed a method of manufacturing gallium nitride LEDs on 200-mm silicon wafers, which provides a cost advantage. With backing for Bridgelux from Toshiba, that process was brought to Kaga Toshiba Electronics Corporation, a discrete products manufacturing facility in northern Japan. Plessey Semiconductors Ltd. (Plymouth, England) has also adopted a GaN-on-Si process for LED production but is presently ramping with 6-inch diameter wafers.
The first product of the Toshiba GaN-on-Si line is the TL1F1 series of LEDs that produce 112 lumens at 350-milliamps current. The packaged parts measure 6.4-mm by 5.0-m by 1.35-mm.
A few years ago, I was working on the design of a data acquisition system (DAS) that would eventually need to be tested when manufactured. It had both high-side current sensing and floating diff-amp input channels. I could either recommend to the client that some expensive equipment be bought and configured for such testing or else design and build some prototypes of a Floating Differential Source (FDS) which would cost much less. I did the latter.
As an engineer, eventually you will have to insert an equation into your written work or presentation. This can be a struggle as equation editors are not always the friendliest. However, there is good news. The equation editor in Word has improved immensely (I am using version 2010 here). In this blog we look at how to insert an equation into a Word document. As a bonus, there is information on how to insert an equation into a web page with an html code generator website.
Wait a minute. Letís see if I understand this. (Here Iím channeling you, the puzzled reader, after youíve grabbed me in the coffee break of a Filter Wizard lecture morning). The frequency of the nth harmonic of a sinusoid is n times that of the fundamental. The nth harmonic distortion is defined as the ratio of the amplitude of the nth harmonic to the amplitude of the fundamental. So the 1st harmonic distortion isÖ the ratio of the amplitude of the fundamental to the amplitude of the fundamental and thatísÖ unity. I. Do. Not. Understand.