LIGO Document D2400263-v1
- The whitening controls concentrator rearranges the binary control bits for a whitening chassis. An ISC whitening chassis has 8 channels that are controlled by 8 bits each for a total of 64 bits. This requires 2 DB37 cables.
However, wavefront sensors and quadrant detectors do not require independent controls for each channel, so 8 bits of binary controls is sufficient to control all 8 channels needed by a wavefront sensor, or the 4 channels needed by a quadrant detector.
The whitening controls concentrator uses 32 bits as input (1 DB37 cable) that are split into 4 groups of 8 bits. Each group has 2 DB37 outputs that can control 4 channels each using the same 8 bits. 1 output is used to control the whitening of a quadrant detector and both outputs are used to control the whitening of a wavefront sensor.
To summarize, the whitening controls concentrator allows us to control the whitening of 4 wavefront sensors or quadrant detectors using only 1 DB37 cable as input.
DCC Version 3.4.3, contact
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