Shown on this slide are examples of typical packages that are used in the industry. Some of these packages are very old. The TO- packages have been on the market for decades, and are still used. Newer types are available, but in power applications designers are sometimes reluctant to use the newer solutions. Hence the evolution has been mostly on the silicon side, rather than the package.  Beginning with the TO-220, which is a non-insulated package with a very good heat transfer which is dissipated to the back portion of the package. For a version that is totally insulated, there is the TO-220FP, which is a similar footprint than TO-220 and is fully plastic. Looking back at the current parameter, the same die in the TO-220 package here will normally have higher current capability than in this package. Next is the IPAK, a smaller three lead package. In applications that require higher power and where lower Rds(on) is needed, this is a good choice. The TO-247 is a pretty large package. The lower group of images shows examples of SMD packages. The D2PAK is shown, as well as the H2PAK which is a version with multiple pins, most of these are the source connection. D2PAK and H2PAK are literally an SMD version of the TO-220 device, the main configuration of the case will be same as the TO-220. The main difference is that there is no tab, and the SMD devices can be back-soldered on the PCB. Similarly, the DPAK is a surface mount version of the IPAK. A more modern approach in packaging is the PowerFLAT. PowerFLAT packages are mostly for low voltage, although some can now be used for high voltage.