Heatsinks for the FMC Fine Delay
This page summarizes the heatsink testing results.
Fine Delay on SVEC (lab test)
Test evironment:*
- crate: 20-slot Wiener VME64x
- crate contents: single SVEC in VME slot 5 with the card under test in FMC slot 2 and FMC TDC in FMC slot 1
- fan speed: 1200 RPM (minimum)
- ambient temperature: 20 deg Celsius
- warm-up time: 8 minutes
Results:*
| Serial No | Configuration | Temperature (degrees Celsius)
|
| CR37 | no heatsink | 59.7 |
| CR09 | small heatsinks on delay and PLL chips | 51.7 |
| CR01 | big heatsink in the rear of the card | 58.6 |
| CR03 | both heatsinks | 52.3 |
Conclusions:*
- big heatsink gives very little temperature drop (1 degC can be
considered measurement error)
- small heatsinks glued on the chips give improvement of 8 degrees C
Detailed temperature measurements on different platforms:
Test environment
- VME: Wiener and Elma crates, with up to 7 SVECs (14 Fine Delays)
installed in subsequent slots. Whenever possible, different
combinations
of VME slots and fan speeds were used.
- PCI Express: Kontron industrial PC, with 5 SPECs and 5 Fine Delays.
- Ambient temperature: 26 - 28 degrees Celsius.
Data:
Wiener 21-slot VME64x crate:*
Slots 4-10
| Slot/FMC | 4/1 | 4/2 | 5/1 | 5/2 | 6/1 | 6/2 | 7/1 | 7/2 | 8/1 | 8/2 |
9/1 | 9/2 | 10/1 | 10/2 |
Conclusions*
- Cards in the middle slots (8-10) are the worst (25 degC difference
over slots 7 and 12). Uneven air flow in the crate?
- FMC1 is approximately 8-10 degrees cooler than FMC2.