Press Release Summary:
Available in 0204-1206 case sizes, LGA Decoupling Capacitor utilizes vertical orientation for internal electrodes, allowing I/O terminals to be located on bottom of capacitor so signals feed directly into vias. Controlled gap between opposing polarity terminals on bottom of capacitor minimizes effective current loop width. Fine Copper Termination employs electromechanical methods to form external metal terminations onto pre-determined areas of any of 6 sides of device.
Original Press Release:
New Avx Technology Reduces Capacitors' Internal Inductance By 50%
MYRTLE BEACH S.C. (June 19, 2006) - AVX Corporation, a leading manufacturer of advanced passive components and connectors, has developed a land-grid array (LGA) capacitor using a fine copper termination process to produce advanced decoupling capacitors that enable improved system performance by providing extremely low ESL. Designated the LGA Decoupling Capacitor, the design builds on the technology employed by interdigitated capacitors (IDC) and reverse geometry multi-layer ceramic capacitors (LICC) to provide much lower inductance in an industry standard geometry chip. By offering very low inductance, the technology is ideal for the latest "on the package" and board-level decoupling applications.
Today's high-speed MPU, GPU and DSP semiconductor device performance can be significantly enhanced by reduced inductance capacitors being positioned very close to the die (on the package). To better address this application and achieve a dramatic reduction in inductance, the LGA Capacitor's design utilizes patented technology and a vertical orientation for the internal electrodes. This allows I/O terminals to be located on the bottom of the capacitor so signals feed directly into the vias.
"The electrode configuration allows loop areas to be greatly reduced," said Mark Obuszewski, Business Manager, AVX. "Because of the current cancellation within the capacitor achieved by the new terminal structure, a relatively simple two-terminal LGA can have an inductance of only 35pH."
The LGA Capacitor design evolved from two basic strategies for reducing equivalent series inductance. The first was to make the area of the current loop formed by the mounted device as small as possible, then use multiple, parallel loops to reduce the net inductance of the device (the idea behind development of the LICC). The second is to break up the longside terminations into segmented terminals of polarity to form several parallel small area current loops such as in IDCs.
MLCCs, LICCs and IDCs all have horizontally oriented electrodes and terminals located on the sides of the capacitors through which electrical signals enter/exit the devices. But with vertical electrodes and precision FCT termination on the bottom, LGA capacitors have very small current loops and therefore very low ESL.
A precisely controlled gap between the opposing polarity terminals on the bottom of the LGA Capacitor minimizes the effective current loop "width". The precision termination is accomplished with a newly patented self-termination process called Fine Copper Termination, which employs electromechanical methods to form the external metal terminations onto pre-determined areas of any of the six sides of the device.
"The process can easily produce asymmetric capacitor terminations, tailored to optimize the low inductance structure, while also designing for better solder mounting and providing test points to be used during capacitor fabrication," said Obuszewski.
Another benefit of the LGA Capacitor is its case sizes. The technology is available in 0204, 0306, 0805, 0508, and 1206 case sizes. The primary variable within this assortment of devices is the cancellation "span", or maximizing the linear distance spanned by the gap between the bottom terminals to minimize ESL. Unlike conventional capacitors such as MLCC, LICC and IDC, the inductance is actually lower for larger case sizes in the LGA Capacitor because the current loop area is set by the design of the internal electrode rather than by the external dimensions of the component.
"From a customer view, this means that maximum capacitance does not have to be sacrificed for lowest inductance," said Obuszewski.
Available in 0204 through 1206 case sizes, the LGA capacitor provides a thickness of 0.5mm up to 1.5mm in larger case sizes. Board-mounting trials at AVX and other sites have shown that parts are readily reflowed, and the mechanical integrity of the LGA solder joint is equivalent, or superior, to those formed with conventional capacitor styles.
Pricing for the LGA Decoupling Capacitor starts at $0.12 in quantities of 10K. Delivery is 10 to 12 weeks.
For more information about AVX's LGA series Capacitors, contact AVX Sales and Marketing at 801 17th Avenue South, Myrtle Beach, S.C. 29578; by calling 843-448-9411; by fax at 843-444-2864; or on the Web at www.avx.com.
AVX Corporation is a leading international supplier of electronic passive components and connectors with 20 manufacturing and customer support facilities in 12 countries around the world. AVX offers a broad range of devices including capacitors, resistors, filters, timing and circuit protection devices and connectors. The company is publicly traded on the New York Stock Exchange (NYSE:AVX).