Difference between revisions of "MCE hardware"

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(MCEv2 5-MDM design notes)
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* ''' Low-noise bias lines '''  
 
* ''' Low-noise bias lines '''  
**
+
How to divide up the Low Noise Bias Signals between the new Bias Cards.
 +
** We need to maintain compatibility with existing Bias Cards which should ground these new backplane signal lines.
 +
** Maximizing the number of Low Noise Bias Signals we could get 10 on each of BC1-BC3 for a total of 30.
 +
** How we route them to the MDM connectors is limited but we have a few options, what seems to be best to me is
 +
** P2 gets LN_BIAS_00 to 07 with 1 spare signal
 +
** P3 gets LN_BIAS_08 to 15 with no spare signal (requires eliminating DET_BIAS_ORG and putting LN_BIAS_12 on this signal) P3 also has PXL_HTR
 +
** P4 gets LN_BIAS_16 to 23 with 1 spare signal
 +
** P5 gets LN_BIAS_24 to 31 with 1 spare signal

Revision as of 23:19, 9 July 2008

MCEv2 5-MDM design notes

  • Jumpers
    • Jumpers for signal pairs have reference designators of JPn and JNn (eg. JP1 and JN1 are signal pair jumpers)
    • These jumpers are called out on the BOM as zero ohm resistors or DNP (do not populate) parts
    • Zero ohm resistors will not be used for connect ground planes, copper traces will be used
  • Low-noise bias lines

How to divide up the Low Noise Bias Signals between the new Bias Cards.

    • We need to maintain compatibility with existing Bias Cards which should ground these new backplane signal lines.
    • Maximizing the number of Low Noise Bias Signals we could get 10 on each of BC1-BC3 for a total of 30.
    • How we route them to the MDM connectors is limited but we have a few options, what seems to be best to me is
    • P2 gets LN_BIAS_00 to 07 with 1 spare signal
    • P3 gets LN_BIAS_08 to 15 with no spare signal (requires eliminating DET_BIAS_ORG and putting LN_BIAS_12 on this signal) P3 also has PXL_HTR
    • P4 gets LN_BIAS_16 to 23 with 1 spare signal
    • P5 gets LN_BIAS_24 to 31 with 1 spare signal