Summary of heat dissipation
Ken Wyllie
11/12/03
Module Structure & Power:
The photon-detector planes are constructed from modules, as shown in the figure
below. Each module consists of 2 hybrid-photon-detectors (HPDs) coupled to a
readout electronics PCB. The heat is generated by electronics components positioned
within the HPDs (pixel chip) and on the PCB. The heat within the HPDs will
effectively arrive at the edge of the PCB to which they are connected by conduction
through the cables in between.
The table below lists the expected power dissipated by each component.
Item
Power (W)
HPDs (pixel chips)
3.6
Pull-ups
2.462
A-pilot
0.075
PINT core
0.9
PINT I/O
2.4
GOLs
0.78
QPLL
0.1
TTCrx
0.251
OPTrx
0.132
VCSELs
0.05
TOTAL
10.750
Photon-detector planes structure:
For both RICH1 and RICH2, the photo-detector planes are made from columns of
modules. Each column is made from a number of modules attached to an aluminium
support frame. RICH1 and RICH2 each have two sides, positioned on opposite sides
of the beam pipe.
The table below lists the numbers of modules and the total power dissipated in the
columns and in RICH 1 and 2. Note that this is just the power from the modules.
# modules per column
Total module power per column (W)
# columns per side
Total module power per side (W)
Total module power per RICH (W)
RICH1
7
75.25
7
526.75
1053.5
RICH2
8
86
9
774
1548
Low-voltage distribution board (LV):
Each column has a low-voltage distribution board (LV), which runs the entire length
of the column. This is also attached to the aluminium frame. It contains voltage
regulators that dissipate power. The table below lists the power dissipated in these
boards.
Total LV power per column (W)
# columns per side
Total LV power per side (W)
Total LV power per RICH (W)
RICH1
58
7
406
812
RICH2
66
9
594
1188
Finally, the table below shows the total power for modules and LV boards together.
Total module power per column (W)
Total LV power per column (W)
Total power (modules+LV) per column
(W)
# columns per side
Total power (modules+LV) per side (W)
Total power (modules+LV) per RICH (W)
RICH1
75.25
58
133.25
RICH2
86
66
152
7
932.75
1865.5
9
1368
2736
The figure below shows how the modules and LV board are arranged in a column of
RICH2.