....Around 1.2 watts/resistor. Mark Skeels Engineer Competition Electronics, Inc. TEL: 815-874-8001 FAX: 815-874-8181 www.competitionelectronics.com M. Adam Davis wrote: > Here's a design guide for a product where they suggest building the > heatsink into the PCB: > > http://www.irf.com/technical-info/appnotes/an-1029.pdf > > A lot of the general recommendations will apply to your situation. > > I haven't been able to find a pcb/copper thermal calculator though. > You may need to experiment. In a previous design I used a 1 square > inch area, both sides with plated through holes every 0.1" to heatsink > a linear regulator with about 1/2 watt dissipation. It was hot to the > touch, but well below 100C. I've heard rules of thumb that surface > mount devices can only push 1-2W into the PCB pads, so while this > would help, if you are pushing more than a watt or two you really > should consider resistor packages meant to dissipate more heat. > > How much power are you dissipating per resistor? > > -Adam > > On Thu, Mar 18, 2010 at 11:44 AM, Mark E. Skeels > wrote: > >> I thought about it........seems like you'd have to try it to see how >> much benefit would be derived...... >> >> Mark Skeels >> Engineer >> Competition Electronics, Inc. >> TEL: 815-874-8001 >> FAX: 815-874-8181 >> www.competitionelectronics.com >> >> >> M. Adam Davis wrote: >> >>> [SNIP] >>> Have you looked at using copper and plated through holes to make PCB >>> heat sinks for the resistors? It can make a huge difference. >>> >>> -Adam >>> >>> >>> >> -- >> http://www.piclist.com PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> >> > > > > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist