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Diametern hos varje boll subtraheras här från diametern hos den minsta bollen och resultaten presenteras grafiskt för att tydliggöra skillnaderna.Variationerna i diameter p g a buktigheter antyder att avståndet mellan kapseln och kortet troligen är mindre i mitten av kapseln än vid kanterna. Den mycket stora bollen i nedre vänstra hörnet indikerar ett bekräftat avbrott.

RK73H1JTTD31R6D_Datasheet PDF

Diametern hos varje boll subtraheras här från diametern hos den minsta bollen och resultaten presenteras grafiskt för att tydliggöra skillnaderna.Variationerna i diameter p g a buktigheter antyder att avståndet mellan kapseln och kortet troligen är mindre i mitten av kapseln än vid kanterna. Den mycket stora bollen i nedre vänstra hörnet indikerar ett bekräftat avbrott.

Common services

The pact comes after the MEF established a relationship with the International Telecommunication Union. In the future, the MEF and the MPLS Forum both could identify common services and interfaces, which could then be brought before official bodies such as the ITU, IEEE and the Internet Engineering Task Force.

RK73H1JTTD31R6D_Datasheet PDF

Since the MEF focuses on service definitions for carriers, two areas of collaboration have characterized the MEF/MPLS Forum relationship. In standard Ethernet service definitions, the groups have defined an Ethernet virtual private line service, with common committed information rate and peak information rate definitions, similar to frame relay, that give Ethernet circuit-like characteristics. For multipoint-to-multipoint operations, the two groups are defining a virtual private LAN service to allow carrier-provided virtual LANs based on Ethernet framing.

Another area of common work is in MPLS Fast-Reroute, which will give Layer 2 Ethernet service a resiliency and recovery period in the same 50-millisecond time frame that characterizes Sonet physical-layer recovery. Chen said that compares with a typical 30-second recovery time for spanning-tree implementations of Ethernet, allowing providers of equipment and service to legitimately claim carrier-class Ethernet” for the first time.

The MEF and the MPLS Forum will work in 2003 on guaranteed-bandwidth methods and quality-of-service mappings.

RK73H1JTTD31R6D_Datasheet PDF

CAMBRIDGE, United Kingdom — Cambridge Positioning Systems Ltd. (CPS) is working with Intel Corp. to integrate its E-OTD location positioning technology into a range of Intel parts targeting the wireless and handheld markets.

Specifically, Intel will integrate the CPS Enhanced Observed Time Difference technology into chips running its Personal Client Architecture (Intel PCA) building blocks. This, the companies said, will enable users of PDAs and smart phones to take advantage of a growing number of commercial location-based services in the United States and beyond.

RK73H1JTTD31R6D_Datasheet PDF

According to Chris Wade, chief executive officer of CPS, Intel's decision is furthervalidation of E-OTD as a global standardized location technology: This is hugely significant for E-OTD, and will further drive the availability of location-enabled devices on a global basis to support the expanding market for commercial and personal safety services.”

Intel has a small stake in the Cambridge-based company.

Turn-on losses are the result of a simultaneous exposure of the component to a large voltage and current during turn-on. These losses are significant for the forward MOSFET as can be seen from Figure 3. Similarly like with the turn-off the speed with which the transistor travels through the active region will determine the amount of losses. Here however we do not have a full freedom to speed up this process as much as possible.

It is because the resistive voltage drop across the forward MOSFET and the layout inductance LSTRAY are the main factors limiting the speed of the reverse recovery process of the lower MOSFET's body diode. The optimal turn-on of the upper MOSFET is relatively slow and in most cases measures should be taken to avoid too speedy transition. This is particularly important if we realize that due to a low plateau level in modern devices the turn-on current of the gate driver tends to be higher than the turn-off current (and we want turn-off current to be as high as possible). Shifting to a more powerful gate driver will reduce the turn-off losses, but may actually make reverse recovery losses worse! With an unfavorable combination of factors this may lead to ringing at the gate of both MOSFETs, then multiple switching transitions, shoot-through and the destruction of the semiconductors!

Let's note that the body diode needs a fixed (roughly) amount of charge to recover its voltage blocking capabilities. Speeding up the upper MOSFET's turn-on will shorten the reverse recovery process but at the expense of higher peak current.

Interestingly, against the common wisdom, the parasitic inductance of the layout LSTRAY plays a POSITIVE role during the turn-on of the upper MOSFET. It slows down the rate of the rise of the reverse recovery current, allowing the body diode to recover with lower peak current. This lower peak current results in a lower dv/dt of the drain to source voltage when the body diode finally snaps in. Conversely, fast turn-on of the forward MOSFET, combined with a very low inductance layout results in a very abrupt reverse recover process with multiple nasty side effects:

– high current stress on the forward MOSFET

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