Monthly Archives: February 2013

Thermal Performance

Reducing the PCB in size certainly has some benefits , however, the reduction of surface area can also easily reduce thermal performance, if care is not taken. The LED driver chip LT3496 has a rather large (compared to the size of the chip 😉  ) thermal pad on the underside that is reflow soldered onto the top ground plane of the PCB. Also thermal vias are placed directly under the pad and surrounding area to help conduct the heat to the bottom ground plane. Both planes serve as heat spreaders. So the question that interested me was how much ground plane is necessary and how many vias are needed, what size should they have and how densely (or not) should they be spaced ? Read the rest of this entry