Thank you for downloading this product training module produced by 3M Electronic Solutions Division for Mouser. In this presentation, we will discuss

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2 Thank you for downloading this product training module produced by 3M Electronic Solutions Division for Mouser. In this presentation, we will discuss a new 2mm hard metric connector that has been designed for speed and performance of next generation CompactPCI applications while still supporting legacy equipment. 2

3 CompactPCI is a standard designed to ensure the interoperability of modular embedded systems, single board computers and backplane systems. It is driven by the PCI Industrial Computer Manufacturers Group (PICMG pronounced pick-mig ), a consortium of over 250 companies which collaboratively develops open specifications that adapt PCI technology for use in high-performance communications networking and industrial computing equipment. 3

4 Since its launch, PICMG s CompactPCI standard has proved to be very popular among modular system designers, installers and users alike. However, the J2 connector of current CompactPCI embedded computers cannot support the high density pin-out of high speed differential signals that many new applications demand. Any changes to the standard have to be made mindful of the need for backward compatibility to support investments in legacy PCI bus cards and backplanes fitted with 2mm Hard Metric (HM) connectors. 4

5 To take advantage in advances in serial data transmission technologies, PICMG is upgrading its popular CompactPCI standard. PICMG s draft standard 2.30 (pronounced two dot thirty ) creates a pin-out for the J2 connector that supports multiple serial protocols and calls out the 3M Ultra Hard Metric (UHM) Socket Connector. This new connector provides the much improved signal integrity performance required to transmit multiple high speed protocols, while still mating to a standard 2mm HM backplane header. 5

6 2mm HM Connectors have been industry work horses for many years, in part because they have been adopted into many popular backplane standards such as PICMG s CompactPCI and VITA s VME 64x. Their popularity stems from the fact that 2mm connector systems increase signal density over.100 systems; they are available in various modular form factors; and they are cost effective. 6

7 Backplanes are being challenged to move from low speed parallel bus applications to high density, high speed serial point-to-point differential signal transmission, such as SATA/SAS, PCI Express, Gigabit Ethernet and USB. As a result today s systems require connectors optimized for very high densities of multi-gigabit per second differential signals. 7

8 Unfortunately, unshielded 2mm HM connectors are limited by their susceptibility to crosstalk especially in applications requiring higher signal densities combined with higher data rates. Severe crosstalk shown by the white bands on this eye pattern is due to lack of isolation between neighboring signals making unshielded 2mm Hard Metric connectors unusable in high speed, high signal density applications. Consequently designers have had to sacrifice signal pins and convert them to grounds thus significantly reducing number of channels available for signal transmission. 8

9 The Ultra Hard Metric (UHM) connector from 3M addresses these signal integrity limitations of unshielded 2mm HM connectors. Firstly, they are fully shielded with the lowest crosstalk high signal density of any 2mm HM Connector available today. Secondly, they are designed to be intermateable with standard 2mm HM vertical backplane headers. Thirdly, UHM connectors are controlled impedance and offer 7 Gbps or higher performance when mated to standard 2mm HM headers. This is why PICMG has chosen the 3M UHM Socket for the J2 connector in its draft 2.30 standard. 9

10 Compared to an unshielded 2mm HM connector the fully shielded UHM connector displays significantly reduced crosstalk. In addition the UHM shield design provides a controlled impedance path which minimizes insertion loss and rise time degradation. A key point is that by improving the signal isolation, more of the signal pins can now be used for high speed signals significantly increasing the number of channels available for transmission compared to the unshielded 2mm HM connector pin-outs as a matter of fact, as many as two times more channels can be used for high speed signals. 10

11 The key innovation that enables high signal density at higher speeds is the addition of internal shielding. In the UHM Connector vertical and horizontal shields are placed between each column and row in order to isolate each signal contact. For differential signals this allows the designer to utilize either row differential or column differential formats as shown here. This shielding is designed to control the differential impedance as close as possible to 100 Ohms validated here in this TDR profile of a UHM socket mated to a standard CompactPCI header. 11

12 In addition to improving signal integrity, the UHM right angle socket was designed to be mechanically compatible with legacy 2mm HM designs. This required the connector to be intermateble with 2mm HM headers designed to IEC It also required the connector to be PCB footprint compatible. It is important to note that the UHM connector s internal shielding (described on the last slide) is connected to the same PCB row as CompactPCI EMI shields are terminated to. This makes it possible to use the UHM socket as a drop-in replacement for the existing connector on the daughter card. 12

13 To characterize the signal integrity of a UHM socket mated to a standard 2mm Hard Metric header two test boards were designed, a header board and a socket board to simulate a backplane mated pair. Test signals were injected into and out of this mated pair via these test boards so some of the measurements we will review include the losses from the test board traces where total PCB traces of 127mm are included in the measurement. 13

14 The so-called eye pattern is one of the key tests used to characterize the differential data rate performance of the UHM socket mated to a header. In this example, the measurement from a digital sampling scope is used to demonstrate the quality of a 7 Gbps (gigabit per second) eye pattern. Including the losses from board traces a i.e. total length of 127mm of traces the scope still measured a significant eye opening of approx 110mV for 7Gbps with relatively low jitter. 14

15 Characteristic impedance is another signal integrity property that is typically measured to characterize the performance of a connector system. The differential characteristic impedance of the UHM socket was designed to match 100 ohm environments, which are typical of high speed serial protocols. When mated to a HM header, the test shows the impedance profile of the UHM socket to be approximately 100 ohm including the via of the socket at 33 picosecond rise time. 15

16 In addition to eye pattern and impedance measurements, 3M has conducted extensive S Parameter testing and modeling. The plot shown here is the modeled differential insertion loss for the UHM socket mated to a standard 2mm CompactPCI 5+2 (pronounced five plus two ) HM Header. The curve indicates very low loss, that is less than 1 db for frequencies of greater than 4GHz. 16

17 In summary, the Ultra Hard Metric (UHM) connector from 3M offers a direct way to improve the performance of legacy and new systems built in accordance with PICMG CompactPCI standards. Its full shielding provides the lowest crosstalk, high signal density of any 2mm Hard Metric connector on the market today, while its controlled impedance characteristics offers performance in excess of 7Gbps. UHM connectors are intermateable with both legacy and new equipment built with connectors meeting IEC Being footprint compatible with existing PCB layouts, UHM connectors are drop-in replacements for standard 2mm HM sockets. For these reasons, UHM socket from 3M is defined in draft PICMG CompactPCI standard 2.30 for the J2 connector. 17

18 For more information including technical specifications, 3D and SI models, visit 18

19 Thank you for downloading this presentation on the 3M Ultra Hard Metric (UHM) Socket Connector for next generation CompactPCI equipment designs. 19