General Technology Description
USB is a point to point connection designed as a replacement for legacy serial and parallel communications. One of the most important features of USB is that power can be supplied using the same cable as data. One end is the master, the other the slave and this is fixed except in the case of USB-OTG (on the go). USB-OTG was introduced to allow the host – function roles to be arbitrated.
Terminations are usually by the original standard ‘A’ and ‘B’ connectors though mini and micro versions exist. Device functions may be hot plugged. Up to 127 functions are allowed per host port by fanning out into a tree structure using hubs.
Implementation Options
USB-1.0
USB-1.1
USB-2.0 specifies speeds of:
“Low-speed“ at 1.5Mbits/s
“Full speed” at 12Mbits/s,
“High speed” with 480Mbits/s
USB-OTG
Wireless USB
USB-3.0
| Technology Group | Related App Notes | Standards |
| Implementation Method - USB | |||||
| Method | Speed (Mbps) | Mfr Chosen | Part # | Kit # | TF Kit |
| Low Speed | 1.5 | FTDI | FT232RL FT245RL | UM232R UM245R | Yes |
| Full Speed | 12 | Cypress | CY7C64713 | CY3674 | Yes |
| High Speed | 480 | Cypress | CY7C68016A | CY3684 | Yes |
| OTG | n/a | NXP | LPC2468 | OM11006 | No |