Editing PCB Footprints

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Any other tips?
 
Any other tips?
 
== high-power footprints ==
 
 
When MOSFETs and image sensors get warm, they don't work as well.
 
Many ICs are guaranteed to work only up to 85 °C.
 
"Automotive grade" ICs are typically guaranteed to work only up to 125 °C.
 
 
Several of the most popular ways to keep a part cool involve footprints:
 
 
* In general, larger packages (such as "Power-SO8 LFPAK"[http://www.nxp.com/documents/leaflet/75016838.pdf][http://www.onsemi.com/pub_link/Collateral/AND9137-D.PDF], TO-220, and D2PAK packages), with larger footprints, can handle more power than smaller packages (such as TO-92 and SOT23 packages). Often people don't know ahead of time if the small, cheap voltage regulator will be adequate, or if they will need the larger part.
 
** Some people prefer a "universal layout" that supports practically any 3-pin voltage regulator.[http://www.robotroom.com/PCB-Layout-Tips.html]
 
 
* Some heatsinks are designed to mount in holes drilled through the PCB.
 
** Some people make a separate "heatsink footprint", often with a corresponding "heatsink schematic component".
 
** Other people make a single footprint such as "TO220_plus_heatsink" that has all the holes for a TO-220 package and a TO-220 heatsink all lined up perfectly relatively to each other.
 
 
* Many people use a square inch or more of PCB copper as a heat sink. Enlarged copper mounting pads, on one or both sides of the PCB, help keep the component closer to ambient temperature. ... thermal vias ? ...
 
** Some people make a "power footprint" that includes a big patch of PCB copper as a heat sink.
 
** Some people make a "power footprint" that includes a big patch of PCB copper on both the top and bottom as a heat sink, and thermal vias between them.
 
** Many people add a "flood fill"/"filled poly" on the PCB. Zhang. "PCB layout considerations for non-isolated switching power supplies".[http://www.edn.com/design/components-and-packaging/4390811/4/PCB-layout-considerations-for-non-isolated-switching-power-supplies]
 
** AN1028: "Maximum Power Enhancement Techniques for SOT-223 Power MOSFETs".[https://www.fairchildsemi.com/an/AN/AN-1028.pdf]
 
** "Soldering and Mounting Techniques: Reference Manual"[http://www.onsemi.com/pub_link/Collateral/SOLDERRM-D.PDF], in particular, "Figure 2. Thermal Resistance versus Drain Pad Area for the DPAK Package" and "Figure 3. Thermal Resistance versus Drain Pad Area for the D2PAK Package".
 
** "Filling in empty spaces on your printed circuit board with copper areas [helps] heat dissipation. This is true even if the copper fills are not electrically connected" -- David Cook[http://www.robotroom.com/Thermal-PCB-Motor-Driver-Tests-4.html]
 
 
  
 
== The Open Symbol Project ==
 
== The Open Symbol Project ==
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== Contributing ==
 
== Contributing ==
 
Yes, please do!
 
Hit the "Upload file" link in the left column, and select your PCB footprint file.
 
  
 
Please take a look at [[Talk:PCB_Footprints#Contributing]].
 
Please take a look at [[Talk:PCB_Footprints#Contributing]].

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