... | ... | @@ -17,16 +17,16 @@ blocking outputs/crate, that can be supported by the design. |
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## Measurement procedure:
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- A conv-ttl-board is installed on an ELMA crate with an RTM board.
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<!-- end list -->
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- A worst case pulse frequencies are generated by the board (Board
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running with gateware pulsetest enabling settable output
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frequencies).
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- All blocking outputs are terminated with a 50Ohms resistor.
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- Worst case pulse frequencies are generated by the board (Board
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running with gateware
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[pulsetest](https://www.ohwr.org/project/conv-ttl-blo-gw/wikis/Pulsetest)
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enabling settable output frequencies).
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- The current consumption of the board will be measured for short
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250ns pulses and long 2.2 us pulses.
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250ns pulses and long 1.2 us pulses.
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- The SysMon on the ELMA crate allows access to current sensor data
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from a telnet prompt (Type command @ \> current@).
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from a [telnet prompt](https://www.ohwr.org/project/conv-ttl-blo/wikis/Documents/ELMA-SysMon-User-Manual) (Type
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command @ \> current@).
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- The number of channels running is gradually inctremented and current
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consumption from the crate is recorded for the number of channels.
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The table below shows the current consumption measured by the crate,
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... | ... | @@ -37,6 +37,7 @@ blocking outputs/crate, that can be supported by the design. |
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<tbody>
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<tr class="odd">
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<td><b> Number of active channels </b></td>
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<td>_ Number of outputs</td>
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<td><b> 250ns @2MHz </b></td>
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<td><b> 250ns @500kHz </b></td>
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<td><b> 1.2us @100kHz </b></td>
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... | ... | @@ -44,6 +45,7 @@ blocking outputs/crate, that can be supported by the design. |
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</tr>
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<tr class="even">
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<td><b> 1 </b></td>
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<td>3</td>
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<td>1.7A</td>
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<td>1A</td>
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<td>2A</td>
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... | ... | @@ -51,6 +53,7 @@ blocking outputs/crate, that can be supported by the design. |
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</tr>
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<tr class="odd">
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<td><b> 2 </b></td>
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<td>6</td>
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<td>2.7A</td>
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<td>1.3A</td>
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<td>2.6A</td>
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... | ... | @@ -58,6 +61,7 @@ blocking outputs/crate, that can be supported by the design. |
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</tr>
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<tr class="even">
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<td><b> 3 </b></td>
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<td>9</td>
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<td>3.75A</td>
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<td>1.9A</td>
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<td>3.4A</td>
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... | ... | @@ -65,6 +69,7 @@ blocking outputs/crate, that can be supported by the design. |
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</tr>
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<tr class="odd">
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<td><b> 4 </b></td>
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<td>12</td>
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<td>4.6A</td>
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<td>2A</td>
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<td>3.8A</td>
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... | ... | @@ -72,14 +77,16 @@ blocking outputs/crate, that can be supported by the design. |
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</tr>
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<tr class="even">
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<td><b> 5 </b></td>
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<td>-</td>
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<td>15</td>
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<td>OVERCURRENT</td>
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<td>3.25A</td>
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<td>3.9A</td>
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<td>2.9A</td>
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</tr>
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<tr class="odd">
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<td><b> 6 </b></td>
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<td>-</td>
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<td>18</td>
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<td>OVERCURRENT</td>
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<td>3.75A</td>
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<td>4.2A</td>
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<td>3.2A</td>
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... | ... | @@ -87,12 +94,17 @@ blocking outputs/crate, that can be supported by the design. |
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</tbody>
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</table>
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As can be seen from the table, operation at
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ver
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## Conclusions and recommendations:
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Maximum current consumption is fast reached at higher frequencies.
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As The crate will shut off the +12V power supply at 5.5A, the +12V fuse can be selected at 5Amps, which will offer extra protection to the board.
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## Conclusions and recommendations:
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### Con
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- Maximum current consumption is fast reached at higher frequencies.
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- By adopting worst case values as an indicator of extreme use of the
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board, a limitation may need to be imposed on the number of active
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blocking outputs per crate:
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- For 250ns pulses, the limit is 12 BLO outputs per crate
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(Regardless of the number of CONV-TTL-BLO boards).
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- For 1.2us pulses, the limit is 18 BLO output channels per crate
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(Regardless of the number of CONV-TTL-BLO boards).
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- As The crate will shut off the +12V power supply at 5.5A, the +12V
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fuse can be selected at 5Amps, which will offer extra protection to
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the board.
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