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Alex, Thanks for the comments. I plan to have out this evening a new draft that incorporates answers to the more obvious questions and the addition to Clause 11 to answer some of Mark’s comments. Any changes are subject to committee approval. The issue with Figure 12-2 was a technical one in that it did not transfer from the Word version of the draft to the pdf version of the draft. While the figure is probably ok in its present form, if pushed, Mark wanted the opportunity to redraw it to get it into shape for publication. The table that was included in the figure showed cable diameters that are probably directed at the specific construction from Steve Sedio as presented in a slide set to the UPAMD committee. Mark’s redo of the figure will correct this. As for your comments that need to be addressed: Comment 1 – I have asked the IEEE editorial staff about the proper representation of Chinese names. The name as shown is as submitted. I did note that during the Olympics, all Chinese athletes’ had their name presented in a similar manner. So far the suggestion from Joan is to leave it as it is from now and make an editorial change later when the IEEE publication staff determines the proper form. Comment 2 – I am having difficulty tracking the requested change down. Can you please provide the line number and a little more of the context. Comment 3 – I will recommend acceptance. I have modified the draft accordingly. Comment 4 - I will recommend acceptance. I have modified the draft accordingly. Comment 5, and 6 - I will recommend acceptance. I have modified the draft accordingly. Technical Comment 7: The vote of the committee on 3 July was to eliminate the Conformity Clause but keep the Certificate Number as RFU with a current value of 0. See minutes from 3 July meeting. The Clause was removed. I will recommend that we keep the certificate wording as it is. Technical Comment 8: The use of a unique identifier for each device has never been questioned. It is an integral part of the communications and identity of the devices. I will recommend against the removal of the EUI structure. EUI assignments are through the same IEEE RA process that generates Ethernet addresses and in this case serve a similar function. These assignments will also be the basis of IPv6 messages directed through the attached network. Comment 9 - I will recommend acceptance. I have modified the draft accordingly. Comment 10 - I will recommend acceptance. I have modified the draft accordingly. Comment 11 - I will recommend acceptance. I have modified the draft accordingly. Technical Comment 12 - I am not sure what to do with this. This was the goal as first accepted by the committee at the time of formation. This will change the history of the committee, a difficult task. It is in an informative appendix as background information. Revising the original goals to match the draft is a subject for discussion. This brings up the question of the power goal that was changed by vote of the committee. The following additions have been proposed for Clause 11 to address the pins and connector. 11.4 Connector Pins This connector design is based on the use of “POGO” spring loaded pins. This style of connector pin has high durability with very high usage cycles specified. Life expectancy for these connectors is to be up to 10 or more years of regular use. POGO pin connector design also support usage in docking station and other application where a blind mate style of connection is needed. 11.4.1 Main Power Pins Main power pins should be capable of handling currents of up to 9 Amps with a temperature rise of 10 C and a contact resistance of 20 milliohms or less. Maximum current for power rail connections is expected to be less than 7 Amps. This load will be spread over two redundant connections, unless one is blocked. Each pin shall be capable of supporting the maximum current under the conditions that one of the pair carrying the same potential is making a high resistance contact or no contact at all. Mid Stroke force for the main power pins is designed around a 120 gram expectation. Maximum mid stroke force shall be less than 150 grams. Main power pins are designed around the Mill-Max 0851 series of pins. Many other manufacturers fabricate a pin with similar characteristics. The maximum diameter of the pin in the connector shell is specified as 2.54 mm to provide separation of the pins in the connector. The center to center distance between Vneg and Vpos power pins on each end of the connector is 2.8mm. Mill-Max has a Slim Line version of the 0851 pin to meet this criterion. A surface feature is added between the Vpos and Vneg pin to add creepage distance for a minimum of 2.0mm. This distance is required to support a Pollution Degree 3 environment, as specified in ISO 60950-1, Second Edition 2005-12 Table 2N, for the 60V potential difference between the pins. Physical contact pad separation is 1.53mm. 11.4.2 Communications Pins CAN bus pins are smaller than the main power pins and carry a maximum current of less than 100 milliamps. Contact resistance shall be less than 25 milliohms. Mid stroke force on these pins is designed around a 60 gram target and shall not exceed 75 grams. Communications pins are designed around the Mill-Max 0951 series of pins. Maximum pin diameter in the connector shell is less critical than the main power pins as center to center spacing between communications pin is 1.9mm and center to center spacing between communication pins and Vneg power pins is 2.124mm. Many other manufacturers fabricate similar pins. 11.5 Connector pin sequencing Sequencing is required for the main power and communications pins. The communication pins shall be the last to mate on insertion and the first to break contact on plug separation. This assures that the power pins are engage before the communications pins are engaged. Sequencing is required to create the low energy connect and disconnect strategy to reduce the stored energy on the main power pins to below 15uJ at the time of contact or disengagement. See Appendix A for more details. Pins may be positioned in the connector body such that each pin is compressed to mid-stoke position with a fully mated connector on target. The compression force of these pins in the fully mated position is discussed below. Vertical/Normal insertion shall cause the main power pins to be compress 0.44mm prior to communications pins contact. Vertical/Normal separation will provide for the separation of the communications pins 0.44mm prior to the separation of the main power pins. 11.6 Connector Mating Force Several sources contribute to the force required to maintain the connector fully mated to the target. Sources include the compression force of the spring, POGO, pins and the seal on the connector that is used to keep dust and liquids out of the connector. These are quantified in Table 11-1. Table 1 1-1 Connector Mating Force
All pin spring compression forces shall be below the maximum force listed in Table 11-1 in the fully mated position. Implementations should try to achieve the nominal forces listed in the table. Connector seal compression force is expected to be age and temperature dependent. The maximum force required to compress the seal to the fully mated position shall remain below the Maximum Force shown in the table. 11.7 Connector Retention Force Retention characteristics of the UPAMD connector is intended to have two levels of retention. Low retention position that will support easy separation of the connector to reduce tripping hazard. High retention position the will firmly attach the connector to the device for use in high acceleration conditions and for use in less accessible area where unintentional separation in not desired. 11.7.1 Low Retention Connector Force Built in tension caused by the pin springs and the seal, as detailed in Clause 11.6, is added to the gripping force required for the low retention force mode. Separation of the connecter in this condition should require no more than 16 Newton’s applied to the cable. Under this condition the gripping force is the sum of the up to 16 Newton’s applied externally and the 8.1 Newton’s of the internal force. This will require the clamp to support approximately 24 Newton’s of force. 11.7.2 High Retention Connection Force Retention in this state is limited by the requirement not to damage the edge of the connector gripping position. This force shall be not less than 40 N (4 kilograms) in addition to the 8.1N static load. Total retention force on the connector device housing will be 48 N (4.9 kilograms). Table 12-3 below needs to be revised, my suggestion are show here.
Respectfully; Bob Davis Chair UPAMD/P1823 bobd@xxxxxxxx 408.353.5990 desk 408.857.1273 cell bob.davis.scsi.com Skype From: Schneider, Alex [mailto:ASchneider@xxxxxxxxxxxxxxxxxxxxx] Bob and colleagues, It is obvious from these results that a strong voice exists for revision of section 12.2, page 93. I didn’t catch that but in retrospect I agree. Mark and the Connector Committee are listed on the agenda as having the ball on this issue. Resolution of the comments related to such a complex change should not be the subject of a single yes/no vote; a draft of this section with appropriate modifications should be circulated so we can intelligently comment. Given that our meeting is at 0000Z, would it be reasonable to ask that such a draft be sent by 1800Z? Thanks. Alex From: upamd@xxxxxxxx [mailto:upamd@xxxxxxxx] On Behalf Of Bob Davis UPAMD, Attached, and below, is the agenda for the UPAMD Working Group Meeting to be held tomorrow a the 5PM PDT time slot. This meeting will be hosted by Anne Marie Kelley of the IEEE while a new arrangement is being made for future UPAMD meetings. Note that this meeting has a password = standards The main topic of this meeting will be to address the issues from the working group ballot of the UPAMD draft. The attached spread sheet has the votes and comments recorded. We will discuss and approve responses to these comments. Note that the voting by the voting members of the UPAMD has approved the draft. As we make changes to reflect the negative vote and comments, the draft will then be re-circulated to give the voters a chance to change their votes. If successful, this recirculation will conclude with the approval of the draft of the standard. UPAMD will then vote to report this out to the MSC for Sponsor Ballot. The MEC will proceed the Sponsor ballot and may require a little more work from the committee. We are almost done. -=-=-=-=- Universal Power Adapter for Mobile Devices (UPAMD) Working Group Start Time: 18 September 2012 5:00 P.M. PDT UTC-8 (0000GMT/Zulu 19 September 2012) World Wide Local Dial in telephone numbers see Intercall’s list This will be a WebEx meeting WebEx Meeting Number: 254 995 595, password – standards https://ieeemeetings.webex.com/ieeemeetings/j.php?ED=190319198&UID=0&PW=NZTI3MDE5MTky&RT=MiM0 Call-in toll-free number: 1-866-203-0920 (US/Canada) Conference Code: 335 449 7653 Preliminary Agenda Call to Order UPAMD Working Group meeting - Bob Davis 0000Z 19 September 2012
V. Ballot and Comment Review a. Review Comment and agree on responses. VI. Communications Subcommittee – Edgar Brown a. Draft progress with new power diagrams VII. Power Subcommittee VIII. Connector Subcommittee – Mark Anderson a. Update on figure 12-2. For cable b. Ferrite strategy, if needed for cable. c. Target definition for optical link study – Statement of Objective IX. New Business X. UPAMD Working Group Meeting Schedule: a. 25 September 2012 at the 5PM Pacific time slot b. 09 October 2012 at the 5PM Pacific time slot XI. Other concerns of the group it needed a. Subcommittee meetings are scheduled in same time slot as Working Group meeting. i. Connector Committee – same week on Thursday. ii. Communication Committee meets following week on Tuesday iii. Power Committee - meets following week, on Thursday XII. Adjournment. Please send any changes or additions to Bob Davis bobd@xxxxxxxx. -=-=-=-=- Topic: MSC Telecon Respectfully; Bob Davis Summit Computer Systems, Inc. 408.353.5990 desk 408.857.1273 cell |