Differences in DDR3 memory

DDR3 memory uses 8-bit prefetch design, which is twice as fast as DDR2 4-bit prefetch design. Its operating frequency is between 800MHz-1600MHz. In addition, the DDR3 specification requires that the voltage be controlled at 1.5V, which is more power-efficient than the DDR2 1.8V, and the heat output is smaller. In addition, DDR3 uses ASR (Automatic self-refresh) design to ensure that the frequency of updates is reduced to reduce the temperature without losing data. From the perspective of the overall specifications, DDR3 is not much different from DDR2 in terms of design ideas. The method to increase the transmission rate is still to increase the number of prefetched bits. However, just like the comparison of DDR2 and DDR, at the same clock frequency, the data bandwidth of DDR2 and DDR3 is the same, but DDR3 has greater potential for speed increase.
In summary, DDR3 memory has the following advantages:
1. Higher external data transmission rate 2. More advanced address/command and control bus topology 3. To further reduce power consumption while ensuring performance 4. To meet the above requirements, DDR3 is adopted on the basis of DDR2. The following new designs:
5.8bit prefetch design, DDR2 is 4bit prefetch, so the DRAM core frequency is only 1/8 of the interface frequency, DDR3-800's core operating frequency is only 100MHz
6. Use a point-to-point topology to reduce the burden on the address/command and control bus. 7. Use a production process below 100nm to reduce the operating voltage from 1.8V to 1.5V and increase the asynchronous reset and ZQ calibration.