Hi all,
The following is our analysis and recommendations for the above comment.
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Vpd vs. Vpse during transient when using Pclass_PD
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Class
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Vpse
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Ktran
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Vtran_low
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Rch
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Pclass_PD
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k
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Ppeak_PD
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Vpd
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5
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50
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0.076
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46.2
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6.25
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40
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1.05
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42
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39.94072
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36
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ok
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6
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50
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0.076
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46.2
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6.25
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51
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1.05
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53.55
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37.7581
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36
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ok
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7
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52
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0.076
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48.048
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6.25
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62
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1.05
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65.1
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37.79544
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36
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ok
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8
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52
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0.076
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48.048
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6.25
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71.3
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1.05
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74.865
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35.49255
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36
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fail
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Vpd vs. Vpse during transient when using Ppeak_PD
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5
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50
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0.076
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46.2
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6.25
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40
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1.05
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42
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39.56542
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36
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ok
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6
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50
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0.076
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46.2
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6.25
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51
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1.05
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53.55
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37.20399
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36
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ok
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7
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52
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0.076
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48.048
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6.25
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62
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1.05
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65.1
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37.07305
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36
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ok
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8
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52
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0.076
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48.048
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6.25
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71.3
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1.05
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74.865
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34.4761
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36
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fail
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Adjusting Ktran to get 36V for Ppeak_PD
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8
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52
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0.057746
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48.99723
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6.25
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71.3
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1.05
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74.865
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35.99974
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36
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ok
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Adjusting Ktran to get 36V for Pclass_PD
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8
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52
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0.069645
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48.37846
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6.25
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71.3
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1.05
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74.865
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35.99998
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36
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ok
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Options
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1. To select 5.5% instead of 7.6% for class 8
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2. Use Pclass_PD and not Ppeak-PD due to thefact that statistically it ha slow chance to happen, resulting by changing Ktran from 7.6% to 6.9%
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Page 192 line 47 says that Ppeak requirements is specified for PSE static voltage i.e. not overload and transient at the same time
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Reccomendations
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We recommend to use Pclass and not Ppeak due to (2). This results with reducing Ktran from 7.6% to 6.9% for class 8 only
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Please review and send your inputs.
Yair, Dylan, Chris, Alon
Darshan Yair
Chief R&D Engineer
Analog Mixed Signal Group
Microsemi Corporation
1 Hanagar St., P.O. Box 7220
Neve Ne'eman Industrial Zone
Hod Hasharon 45421, Israel
Tel: +972-9-775-5100, EXT 210.
Cell: +972-54-4893019
Fax: +972-9-775-5111
E-mail: <mailto:ydarshan@xxxxxxxxxxxxx>.