What is the role of I3C Protocol in DDR5 ?

DDR5 has significant improvement over DDR4. DDR5 offers higher bandwidth with data rate upto 6.4 Gbps and operates at 1.1V consuming lower power compared to DDR4.The channel architecture is also significantly different compared to DDR4. DDR5 has two independent channel unlike DDR4. In order to support additional performance and monitoring there are some interesting features as well.

Temperature Sensor IC on DIMM

DDR5 hast two IC for temperature sensor TS1 and TS2. The purpose of these sensors is to monitor thermal changes in DIMM. Each of these DIMM are strategically place at the end of DIMM to get the complete thermal profile of the DIMM. These temperature sensors use I3C interface Temperature sensor TS1 and TS2 can be controlled for fan speed changes and ensure the temperature profile is correctly maintained in the DIMM.

Image of DIMM with Temperature sensor.

Side Band Access:

DDR5 introduced side band bus to access non DRAM modules. The Side band bus is based on MIPI I3C or I3C Protocol. Apart from sideband bus there is also a SPD ie Serial Presence Detect Hub as the number of components have grown on DDR5. The SPD Hub interfaces the internal components of DIMM like RCD ie Register Clock Driver and PMIC and another temperature sensor IC.


Image of the Side band bus

Debugging I3C Interface:

Prodigy has developed state of the art I3C Protocol analyzer. The I3C Protocol analyzer can be used to Debug the I3C Sideband bus in the DDR5 as well it can be used to check the protocol compliance of temperature sensors.

Prodigy I3C Protocol Analyzer