South Korean memory chip rivals Samsung Electronics Co. Ltd. and SK Hynix Inc. have both claimed to be the first company to develop an 8Gbit LPDDR4 mobile DRAM using "20nm class" manufacturing process technology. Both Samsung and SK Hynix use the term 20-nm class to refer to manufacturing processes with minimum geometries of between 20- and 29nm.
LPDDR4, first discussed in March 2012, is the follow-on standard to the LPDDR3 and is expected to find extensive use in mobile equipment such as mobile phones and tablet computers. However, both Samsung and SK Hynix have jumped the gun because the LPDDR4 standard is not expected to be formally set by the JC-42.6 Subcommittee for Low Power Memories until 2014.
Samsung's 8Gbit LPDDR4 uses a Low Voltage Swing Terminated Logic (LVSTL) I/O interface. This interface was proposed to the JEDEC standard body by Samsung has become a standard specification for LPDDR4 DRAM. Using the LVSTL I/O the LPDDR4 chip will be able to transfer data on each pin at 3,200 megabits per second (Mbps), twice that of 20nm-class LPDDR3 DRAMs. The LPDDR4 interface will provide a data transfer performance that is 50 percent higher than the fastest LPDDR3 or DDR3 memory and consuming approximately 40 percent less energy at 1.1 volts.
Other changes in LPDDR4 are the move to a 16-bit wide two-channel architecture and the use of bus inversion to reduce signal interference. The LVSTL I/O interface provides for a 350mV peak-to-peak with a configurable termination. An improved version of LPDDR4, expected in 2015, could move the bandwidth to 4,266 Mbps possibly accompanied by a move of the I/O voltage down to 1V.
SK Hynix's LPDDR4 device also operates at 3,200 Mbps and 1.1V. SK Hynix said it is already providing samples to customers and SoC companies and that it plans to go into volume production in 2H14. SK Hynix said it expects LPDDR4 to be present in flagship mobile equipment at the end of 2014 and to be a commercial part in 2015 and 2016 by when it will be the dominant DRAM for mobile applications.
Samsung did not mention samples but said it plans to provide the 8Gbit LPDDR4 DRAM to customers during 2014 often in the form of four die in a 4-Gbyte package.
"This next-generation LPDDR4 DRAM will contribute significantly to faster growth of the global mobile DRAM market, which will soon comprise the largest share of the entire DRAM market," said Young-Hyun Jun, executive vice president, memory sales and marketing at Samsung Electronics, in a statement. "We will continue introducing the most advanced mobile DRAM one step ahead of the rest of the industry so that global OEMs can launch innovative mobile devices with exceptional user convenience in the timeliest manner."
Related links and articles: