Physical Details
VL-EPICs-36 Reference Manual
13
H
ARDWARE
A
SSEMBLY
The VL-EPICs-36 uses pass-through SUMIT (PCIe) and PC/104 (ISA) connectors so that
expansion modules can be added to the top of the stack. A SUMIT expansion module with a
PCIe x4 lane must be closest to the CPU board. Next on the stack would be an expansion module
with a PCIe x1 lane. Above that, USB, SPI, SMBus and/or LPC SUMIT modules can be stacked.
ISA modules must not be positioned between the VL-EPICs-36 and any SUMIT modules on the
stack.
The entire assembly can sit on a table top or be secured to a base plate. When bolting the unit
down, make sure to secure all eight standoffs (A and B) to the mounting surface to prevent
circuit board flexing. Four standoffs (B) must be used under the stack. These are secured with
four male-female standoffs (C), threaded from the top side, which also serve as mounting struts
for the SUMIT-PC/104 stack. Standoffs are secured to the top circuit board using pan head
screws. See page 11 for dimensional details. Four standoffs and screws are available as part
number VL-HDW-105. Note that the standoffs in this kit are 15.25 mm (0.60 inch), and must not
be mixed with the 15.0 mm standoffs used for non-SUMIT boards.
An extractor tool is available (part number VL-HDW-201) to separate the PC/104 modules from
the stack. Use caution when using the extractor tool not to damage any board components.
S
TANDOFF
L
OCATIONS
Figure 5. Standoff Locations
A
B
C