Two Things : Memory Speed and Efficiency .
LPDDR4 -succeeded in increasing maximum data rates to 3200 Mbp that is 1.7X higher than LPDR3 and operating voltage is reduced by 7% compared to LPDDR3 (1.2 to 1.12 V)
LPD4X -The ‘X’ stands for ‘eXtra’ or ‘eXtended’. I/O voltage ( 0.6V) to save system power and data rate improved from 3200 to 4266 Mbps.
LPDDR5 : Data rate of up to 6,400 Mb/s that is 1.5 times faster than LPDDR4X and power consumption reduced by 30%.
The LPDDR4 offers massive improvement over the previous generation mobile DRAMs and planned for offering higher memory bandwidth. The LPDDR4X is, on the other hand, an optional minor upgrade to the LPDDR4 that reduces the power consumption requirements by almost 55 percent, bringing it down to 0.6 Volts.
LPDDR4 ,LPDR4X and LPDR5 Introduction –
To move further , first begin with the understanding of various Mobile DRAM Solutions .
The LPDDR4 is the fourth generation of LPDDR RAM technology, it is considered to be the DDR4 alternative for the mobile devices. While DDR4 has already been used in high-end PCs and similar systems, their mobile equivalent the LPDDR4 finds heavy usage in Mobile devices.
The LPDDR4 brings ahead faster functionality and lower power consumption. The fundamental difference between then DDR4 RAM used in PCS and the LPDDR4 lies in the fact that they come with smaller bit bus. This helps in lower power consumption.
Compared to DDR4, LPDDR4 offers reduced power consumption but does so at the cost of bandwidth. LPDDR4 has dual 16-bit channels resulting in a 32-bit total bus. In comparison, DDR4 has 64-bit channels.
The LPDDR4 improves the data rates by almost double when compared to the previous generations, the LPDDR3. You can get data rates as high as 3200Mb per sec with LPDDR4 as compared to the 1600 Mb per sec performance on the LPDDR3. The LPDDR3 had one channel, while the LPDDR4 opts for a two-channel design. It offers you 16 Bits per channel, thus providing you a total of 32 Bits. This can be helpful in lowering the power requirements of the core. The short data path ensures that the lower power consumption. This can be quite helpful in improving the operational speed and performance. The LPDDR4 offers a marginal improvement in the power consumption from 1.2 volts on LPDDR3 to 1.1 Volts on LPDDR4.
Another advantage associated with the LPDDR4 RAM is it can be manufactured on a smaller 2x nm process. This helps in going for mass productions and can effectively reduce the price as well.
LPDDR4X is not backward compatible to LPDDR4 and so is LPDDDR5.
