What is DB9 connector and what are the applications of DB9 female and male Connectors? Many people do not understand what is DB9 connector. In fact, DB9 connector is a common electrical connector, is one of the common D-Sub type of connectors. DB9 is the smallest model of D-Subminiature connector, DB9 female connector has 9 pin holes, while DB9 male connector is 9 pins.
In addition, DB9 connector is DE9 D-sub 9-pin connector, just incorrectly called "DB9" connector, where E is the size of the shell. For example, computer first used DB25 connector as its serial and parallel port when PC serial port started to use DE9 D-sub 9-pin connector. However, due to ignorance, it was usually labeled as DB9 instead of DE9 connector, incorrectly using B to indicate the fact of shell size. So now it is common to sell DE9 connectors as DB9 connectors, and DB9 means 9-pin connector with E size shell.