SPEC Fan Design
Certain mezzanines were reported to heat excessively when mounted on a SPEC carrier is some PCs (see Fine Delay Temperature Issues).
The solution we have found to be efficient and cost-effective is an add-on fan unit. The unit consists of a small fan mounted on a PCB acting as a mechanical support and hosting the fan's power supply (a DC/DC converter from 12 V to 5 V). The PCB is attached to the SPEC using the same screws that attach the mezzanine (see photos below). The fan fits in the cutout under the FMC and pumps the air out of the mezzanine area.
Important note:* the fan height (6mm) will fit most of the mezzanines from the OHWR (FmcAdc100m4Cha, FMC Fine Delay, FmcTdc1ns5cha), but is not compliant with the FMC standard, which does not foresee a fan between the carrier and the mezzanine.
The fan unit takes power from the P12V/GND testpoints next to the SPEC power supply. One needs to solder two right-angled pins to connect the fan unit (see photo below):
Design Files
The official EDA release of the fan design and its integration with the SPEC carrier is available in the EDMS. It consists of two projects:
- EDA-03106-V1-0 - the
fan itself.
-
EDA-02189-V4-1
- a SPEC with Fan project, consisting of the latest (V4) release of the SPEC and all the materials (fixings, cables, pins) required to install the fan.
The overview of how the fan is installed onto a SPEC can be found here .