You know the special needs of your LED printed circuit boards, but does your PCB
fabricator really know?
Who you choose makes all the difference.
At RUSH PCB,
we understand that your LED PCBs have particular needs, especially with spillover
light and heat management.
Spillover light is an issue because LEDs spill some light to the side and rear.
You choose a white mask to reflect this light “back out of the box”,
but some “white-reflective” masks change when heated; they become dull
and grow thin during the reflow process and no longer fully reflect the LED’s
light.
RUSH PCB lays down a reflective mask that even after heating holds its luster and
won’t go thin to show any copper color from underneath. We found the best
mask on the market to be Taiyo’s LEW1, because it holds its brilliance and
doesn’t change color, even after the harsh heat of the reflow process.
Heat management for high power LEDs is also an issue, and heat dissipating metal
core printed circuit boards (MCPCBs) goes a long way to solve this problem. The
metal core substrates from Thermagon, Bergquist, Arlon or Univaco help dissipate
the excess heat from the LEDs, but getting the heat from the LED, through the prepreg,
to the metal core is also a concern.
The prepreg’s thickness and how well it’s bonded to the metal core is
crucial. RUSH PCB bonds prepreg that’s thin enough to transfer the heat, yet
thick enough to electrically insulate the copper conductors.
Even the bonding process of this dielectric is important. RUSH PCB uses a process
that doesn’t leave insulating air bubbles between the metal of the substrate
and the prepreg: bubbles that would otherwise slow the heat transfer.
Contact RUSH PCB for more information. We’ve been the PCB fabrication business
for years and we will be glad to help you.