Small
Outline Transistor (SOT)
packages are very small, inexpensive
surface-mount plastic-molded packages with leads on their two long
sides.
Due to their low cost and low profile, SOT's are widely used in consumer
electronics. The
SOT-23
and the
SC-70
packages are two of the most widely used SOT packages today. Note that
aside from these two, there are many other SOT
package types used in the IC industry.
Typical lead counts for the SOT-23 package range from 3 to 8, while
typical lead counts for the SC-70 range from 3 to 6.
Examples of typical dimensions of the SOT-23 and the SC-70 packages are shown in Table 1.
Note that in packages with odd lead
counts,
one side of the package has one less lead than the other side.
This results in lead spacing between two adjacent leads that is twice
the normal lead pitch of the package. Some SOT packages have two different lead
dimensions in the same package. Such packages can have different
lead pitch values, depending on which two adjacent leads they pertain
to.