- Published: Saturday, 04 April 2009
- Written by Digital DIY
- Hits: 5047
The name is an abbreviation for Inter-Integrated Circuit and is pronounced I-squared-C
I2C uses only two bidirectional open-collector lines, serial data (SDA) and serial clock (SCL), pulled up with resistors. The maximum voltage is +5 V, although +3.3 V systems are common and other voltages are permitted.
The I2C reference design has a 7-bit address space with 16 reserved addresses, so a maximum of 112 nodes can communicate on the same bus. The most common I2C bus modes are the 100 kbit/s standard mode and the 10 kbit/s low-speed mode, but clock frequencies down to zero are also allowed.