Surface mount device with compensation for thermal expansion effects

摘要

A surface mount electronic device, attachable to a circuit board, comprises an insulating substrate having a top surface and a bottom surface; a plurality of metallized terminal pads on the bottom surface; and a plurality of leads, each attached to one of the terminal pads by a solder column. Each of the leads comprises a first substantially horizontal lead portion attached to one of the terminal pads by the solder column. A plurality of upturned prongs on the first substantially horizontal lead portion forms a pronged area configured to hold the solder column. A second substantially horizontal lead portion terminates in a free end for attachment to the circuit board. An upwardly curved intermediate lead portion connects the first and second substantially horizontal portions and underlies the bottom surface of the substrate. The lead configuration provides compensation for stresses resulting from mismatching temperature coefficients of expansion between the substrate and the circuit board while providing a small "footprint" and a low vertical profile for the device.