What is I2C Protocol?

I2C stands for Inter IC communication. I2C Protocol is a simple two wire protocol used to communicate between two devices or chips in embedded system.

What is I3C Protocol?

I3C has got the extra I over the standard I2C. Improved Inter IC communication protocol. I3C Protocol has improved over I2C Protocol is many ways. I3C Protocol maintains the backward comparability with I2C Protocol. However it provides advanced features required for modern communication w.r.t to speed and interrupt handling etc.

What is the difference between I3C vs I2C Protocol?


The difference between I3C vs I2C can be understood by knowing the details of the protocol .While some differences are very obvious like improved speed and backward compatibility there are very interesting features worth understanding. The differences are:

  • I3C is power efficient and high speed compared to I2C.
  • I3C supports single data rate (SDR), High Data rate (HDR) modes, through which it can support up to 33Mbps data rate whereas typical I2C network support up to 1Mbps.
  • In I2C, all the operations will happen with static address where as in I3C, I3C master will assign dynamic address to all the slaves present on the bus.
  • Dynamic address assignment for I3C slaves but still supports static address for I2C slaves.
  • I3C has standardized set of common command code (CCC). There are three types of common command codes: Broadcast commands, Directed commands and private.
  • Broadcast commands are like master, which will send CCC to all the slave to set same register value to all slaves present on the I3C bus.
  • Directed commands are like master, which will send CCC to the specific slave to read/write register from the slave.
  • I3C supports In-band interrupt (IBI) on the I3C bus. So separate pins are not required.
  • I3C master will assign dynamic address to the slave as per priority of the slave. In such case master depends on reading PID, BCR, DCR registers from the slave and it will assign dynamic address to the slave which ever slave has lowest dynamic address it has highest priority on the bus. Because any transaction start initially it will be in open drain mode so in that phase any slave or secondary master can give the IBI or secondary master request whoever wins the arbitration it will complete transaction on the I3C bus.
  • I3C supports hot join operation in which slave will send hot join request to master and master will assign dynamic address the slave.
  • I3C has error detection and recovery like (parity check in SDR, parity and 5bit CRC for HDR modes).
  • Multi master operation with well-defined ownership transfer from one master to another master.

What are the Protocol Analyzers to Debug I3C vs I2C Protocol?

Prodigy offers I3C Protocol Analyzer with advanced capability to trigger and capture the I3C protocol based on I3C Protocol specification.

Prodigy I3C Protocol Analyzer 


I3C vs I2C Protocol Analyzer

I3C  Protocol Analyzer

Prodigy also offers I2C Protocol analyzer to capture and decode the I2C packets. I2C protocol analyzer has advanced capability not only to trigger but long allow very long captures which is very useful for the embedded design engineer during the debug.

Prodigy I2C Protocol Analyzer


I3C vs I2C Protocol Analyzer



In conclusion, I3C vs I2C protocol analyzer choice depends on factors like cost and current design. However I3C protocol is gaining traction and will be the de facto interface for most of the chipsets developed in the future. To Read more Blogs on Protocol Analyzer, Click Below.

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