High power, SMD, ceramic-based chip resistors are liable to solder joint failure, cracking, and pulling the solder lands off the PCB. This is because of the difference in the co-efficient of thermal expansion between PCB materials. Stackpole has introduced the SM series of surface mount, molded, wirewound resistors with compliant terminations that expand and contract with the PCB. The resistors deliver a power rating of over 4W, which are not normally supported by a single ceramic substrate film chip resistor. They are available in power ratings from 1 to 4W, in resistance values from 0.01Ω to 5kΩ, and in tolerances of 0.1%. The resistors are suitable for power control, motor controls, protection circuits for motors and utility meters, They are also suitable for optical sources and power meters, aerospace instruments, communication systems, electric vehicles, and medical grade lasers.
