What is Circuit Design

Circuit Designers try to make connections.

6. Putting it all Together

All parts are mechanically, electrically, and thermally connected to printed circuit boards with solder.  Solder is a combination of metals that are chosen for their mechanical and chemical properties as well as their price and environmental impact.

Periodic Table with Highlighted Metals

This periodic table highlights common elements used in solder-metals.

But the metals aren't mixed together randomly.  They are mixed in exact proportions that provide specific thermal and mechanical properties.

Solder Alloys

Solder compositions made of different metals have different transition temperatures.

Hard Way Hughes"Engineers rarely ever consider the solder that is used to connect their parts to their PCBs -- until bad things start happening in their designs.  Then there's a pretty intense study session and a lot of phone calls to other designers to try to figure out what is going on.  There are many solders to choose from, and even something called Transient Liquid Phase Sintering Paste -- which will only melt once."