20121101 ======== nL = Left wing backplane/terminator number n. nR = Right wing backplane/terminator number n. Pictures -------- IMG_7307.JPG Terminator circuit boards 4 different narrrow layouts 3 different wide layouts IMG_7310.JPG Mounted narrow circuit boards IMG_7311.JPG Mounted wide circuit boards IMG_7313.JPG Closeup of Mounted narrow circuit board - 33 ohm at RT13 IMG_7314.JPG Closeup of Mounted narrow circuit board - 75 ohm at RT13 IMG_7316.JPG Closeup of Mounted narrow circuit board (opposite side) IMG_7317.JPG Mounted wide circuit boards IMG_7319.JPG Used 1L at the SALTRO testboard IMG_7324.JPG Missing components on wide terminators (capacitors) IMG_7327.JPG Missing component on narrow terminator 3L (capacitor close to RT15) backplane-terminators-1.pdf backplane-terminators-2.pdf schematics of the two sides of a terminator Comments to schematics: >Alla motstånd förutom Rt2 är 75 Ohm 0805 motstånd och Rt2 är 150 Ohm (diff clock termination). >Alla övriga komponenter är avkopplingskondensatorer i 0805 kapsel. >De flesta bör vara 100nF X7R keramisk kondensatorer (aka avkopplinskondensatorer) men minst en per sida ska vara en >kondensator med minst 10uF X5R keramisk kondensator (aka bulkkondensator). >Det finns två varianter av korten med små placeringsändringar mellan dem men de är likvärdiga på alla sätt och du bör >lätt kunna identifiera komponenterna. >Höger resp. vänster terminator bestäms sedan av hur kontakten löds i. Comments -------- RT13 termination resistor. Some of the mounted terminators had RT13 (readout clock termination) with 33 ohm, some with 75 ohm. All 33 ohm was found to be working with many FECs at DESY testbeam 201209, those with 75 did not. The SALTRO testboard do not work with 75 ohm terminator, but with 33 ohm. At the prototype stage did we use a potentiometer to find the proper RT13 value. The first batch of terminators was with 33 ohm, later batch with 75 ohm. Status of backplanes and terminators ------------------------------------ Backplanes Terminators wide narrow wide narrow comment 1L 1L 1L 1L 75 ohm -> 33 ohm 20121101 2L 2L 2L 2L 3L 3L 3L 3L 4L 4L 4L 4L 75 ohm -> 33 ohm 20121106 1R 1R 1R 1R 2R 2R 2R 2R 3R 3R 3R 3R 75 ohm -> 33 ohm 20121102 4R 4R 4R 4R 75 ohm -> 33 ohm 20121102 One set of L terminators is missing, perhaps the ones at DESY in a bag labelled "BAD". Found one loose wide R at the work area in room B316. Do not know why it is there and if it is working. 20121102 ======== Tested narrow terminator 1L with 33 ohm together with SALTRO testboard - OK Tested narrow terminator 3R with 33 ohm together with 1 FEC - OK Tested narrow terminator 4R with 33 ohm together with 1 FEC - OK Had previously some problem when reading 1000 time samples (full time), seems now gone. Components 75ohm http://se.farnell.com/multicomp/mc0-1w08051-75rfr/resistor-0805-75r-1-full-reel/dp/2129026?in_merch=New%20Products Konding 22uF http://se.farnell.com/avx/08056d226mat2a/capacitor-x5r-0805-6-3v-22uf/dp/1867955 Farnell 1867955 20121106 ======== The terminator labelled BAD was in the box with backplanes and termitors at Lund. It had a 75 ohm terminator instead of 33 ohm. Replaced it and put back a missing 100nF capacitor at the end of the "row" of resistors. 20121108 ======== Tested the "BAD" terminators (see above) with the SALTRO testboard. Working. Labelled them 4L. 20121121 ======== Lennart made 1 set of Left 5L 1 set of right 5R tested them with one FEC, OK.