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I²C bus
EntityQ750469· pop 34· linked from 357 articles

Also known as I2C, I²C, Inter-Integrated Circuit, IIC, i-squared-c

I2C (Inter-Integrated Circuit; pronounced as "" or ""), alternatively known as I2C and IIC, is a synchronous, multi-master/multi-slave, single-ended, serial communication bus invented in 1980 by Philips Semiconductors (now NXP Semiconductors). It is widely used for attaching lower-speed peripheral integrated circuits (ICs) to processors and microcontrollers in short-distance, intra-board communication.

Key facts

Connector <! NOTE: Not a perfect template match, but good enough for now >.name
I2C
Connector <! NOTE: Not a perfect template match, but good enough for now >.type
Serial communication bus
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120px|frameless
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Philips Semiconductors(now NXP Semiconductors)
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Open-collector or open-drain
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1-bit (SDA) with separate clock (SCL)
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0.1, 0.4, 1.0, 3.4 or depending on mode
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Serial, half-duplex
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SDA
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Data Pin
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SCL
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Clock Pin

via Wikipedia infobox

Wikidata facts

Image
I2C.svg
Show 6 more facts
derivative work
Display Data Channel
different from
I²S
Commons category
I2C
discoverer or inventor
NXP Semiconductors
Stack Exchange tag
stackoverflow.com/tags/i2c
time of discovery or invention
1982-00-00
Sources (4)

via Wikidata · CC0

~51 min read

Encyclopedic overview

35 sections
Contents
  • Design
  • Reference design
  • Message protocols
  • Messaging example: 24C32 EEPROM
  • Physical layer
  • Clock stretching using SCL
  • Arbitration using SDA
  • Arbitration in SMBus
  • Arbitration in PMBus
  • Differences between modes
  • Circuit interconnections
  • Buffering and multiplexing
  • Sharing SCL between multiple buses
  • Line state table
  • Addressing structure
  • 7-bit addressing
  • 10-bit addressing
  • Reserved addresses in 7-bit address space
  • Non-reserved addresses in 7-bit address space
  • Transaction format
  • Timing diagram
  • Software Design
  • Operating system support
  • Development tools
  • Host adapters
  • Protocol analyzers
  • Logic analyzers
  • Popular cable systems
  • Limitations
  • Derivative technologies
  • Revisions
  • See also
  • References
  • Further reading
  • External links

I2C (Inter-Integrated Circuit; pronounced as "" or ""), alternatively known as I2C and IIC, is a synchronous, multi-master/multi-slave, single-ended, serial communication bus invented in 1980 by Philips Semiconductors (now NXP Semiconductors). It is widely used for attaching lower-speed peripheral integrated circuits (ICs) to processors and microcontrollers in short-distance, intra-board communication.

In the European Patent EP0051332B1 Ad P.M.M. Moelands and Herman Schutte are named as inventors of the I2C bus. Both were working in 1980 as development engineers in the central application laboratory CAB of Philips in Eindhoven, where the I2C bus was developed as "Two-wire bus-system comprising a clock wire and a data wire for interconnecting a number of stations". The US patent was granted under number . The internal development name of the bus was first COMIC, which was later changed to I2C. The patent was transferred by both gentlemen to Koninklijke Philips NV.

Excerpted from Wikipedia’s “I²C bus” article, available under the CC BY-SA 4.0 licence.

Gallery (14)