Each size of USB connector has two different USB cable types: A and B. These USB cables can be found in three different sizes: Standard, mini and micro. Within standard sized USB cables the USB A connector must be used on devices that provide power, such as computers, and USB B connectors used on devices that receive power, such as peripheral devices. In each standard sized USB cable there are four pins that are defined. There are two pins that are used for power and two pins that are used for differential data transmission. Pins one and four are noticeably longer than two and three. This is so that the pins that are used for power are connected before those that are used to establish the data connection. The difference in pin length therefore avoids the chance that the driver or receiver ports of the data connection will receive awkward or dangerous voltages.
Mini USB cables can be recognised, most obviously by their size, but also because they have an extra pin. This pin is called ID and is not normally connected to the mini connector series but is in place for future enhancements of the standard USB. Mini USB connectors were created for smaller devices such as cameras and phone as the standard sized cables often did not fit. The smallest sized USB cable type is the micro USB connector. This is suggested to be much easier to integrate with smaller devices than the mini USB. The micro USB is also designed to be much hardier than the mini USB and can withstand rougher usage. The ID pin in a micro USB has a function attached to it and is used to signal the master of slave function.
For more detailed information and images of the different types of USB cables head over to www.lammertbies.nl/comm/cable/USB-connector.html
Mini USB cables can be recognised, most obviously by their size, but also because they have an extra pin. This pin is called ID and is not normally connected to the mini connector series but is in place for future enhancements of the standard USB. Mini USB connectors were created for smaller devices such as cameras and phone as the standard sized cables often did not fit. The smallest sized USB cable type is the micro USB connector. This is suggested to be much easier to integrate with smaller devices than the mini USB. The micro USB is also designed to be much hardier than the mini USB and can withstand rougher usage. The ID pin in a micro USB has a function attached to it and is used to signal the master of slave function.
For more detailed information and images of the different types of USB cables head over to www.lammertbies.nl/comm/cable/USB-connector.html
