In
microelectronics, a
dual in-line package (
DIP or
DIL), or
dual in-line pin package (
DIPP) is an
electronic component package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be
through-hole mounted to a
printed circuit board or inserted in a socket. The dual-inline format was invented by Don Forbes, Rex Rice and Bryant Rogers at Fairchild R&D in 1964, when the restricted number of leads available on circular transistor-style packages became a limitation in the use of
integrated circuits. Increasingly complex circuits required more signal and power supply leads (as observed in
Rent's rule); eventually microprocessors and similar complex devices required more leads than could be put on a DIP package, leading to development of higher-density packages. Furthermore, square and rectangular packages made it easier to route printed-circuit traces beneath the packages.