The SM Series from Stackpole Electronics Inc.offers a robust wirewound resistor in a surface-mountable device capable of handling up to 4W in a single part. Some applications require power handling of at least 2W, but design engineers have concerns about parts cracking or solder joint integrity for chip sizes of 2010 or larger. As a result, they are forced to use multiple 1206 size chips, which increase the size and manufacturing cost of the design. A single SM resistor is an ideal solution in that it can handle high continuous power with relatively low heat rise and has compliant metal terminations which eliminate part and solder joint cracking problems.
In addition, the SM Series can operate safely in temperatures up to 275 degrees C. Target applications for the SM series include: Engine controls; Electric motor, fan, and pump controls; Power conversion; Current limiting for circuit protection; Test, measurement, and data acquisition; Precision automation systems; and Thermostats. Pricing varies with size, value, and tolerance, and ranges from $0.33 to $1.15 each in full reel quantities.